ok i am going to put my 2.0l heads on my 2.5l sti short block. which head gaskets do i use?,and is there anything else i should know? i know there is a bunch of guys on here that have done this please share your wisdom with me :)

ok i am going to put my 2.0l heads on my 2.5l sti short block. which head gaskets do i use?,and is there anything else i should know? i know there is a bunch of guys on here that have done this please share your wisdom with me :)

Before you decide to do this hybrid, I found an alternative that you may be interested in.

Most people who get 2.5l hybrid's complain of the cams or heads or both. Mostly the cams. The cost of getting STI cams and an sti shortblock is the same price if you just bought a complete sti shortblock and sold your wrx shortblock complete.

This is of course assuming your shortblock you have now is in working condition. Just and idea.

im doing the same conversion and have the same question.
i need to know what head gaskets to use.
as far as cams goes, in gonna go with crower.

I used the revised rs head gaskets. They are slightly thicker than the sti gaskets so they will lower the compression a little.

I just picked up one today because I have to replace piston #2 which got toasted after my MAF went bad. I have run 26psi on these with out a problem. Daily I run about 22psi.

im doing the same conversion and have the same question.
i need to know what head gaskets to use.
as far as cams goes, in gonna go with crower.

i hope you are going with 272,s because they are not going to make the 264's anymore ,and i could not find anyone who had them good luck in your search:)

u have to use the sti headgasket or equvalent(spelling?)

Im using the cometic head gasket on mine cause its thicker and lowers the compression ratio back down to around 8.5....

thanks carbonrex1 i am going to use the stockers as the tuner says i will be fine since i will be tuned of rthe higher compression.i think the stockers increase compression to 8.9 not much,but it is higher. :)

Ok since nobody has given finite numbers then I will. The first time I built my motor, I used OEM 2.5L Sti head gaskets. This gave me a compression ratio of about 9.17:1(according to Ron at Axis power racing). The car, using a VF22 and Sti-Ra gears pulled a strong 305whp/303wtq on a Dynojet AWD in Miami. I bested a 12.8@109mph at MOROSO.
I got greedy with boost and well, blew #2 and #4 ringlands. SO, I rebuilt my motor. This time using COMETIC head gaskets and ARP head studs. Again using the help of Ron he suggested that I use the .051" thick gaskets. This would put me at a decent 8.5:1 compression ratio.

I recently dynoed my car on our Mustang AWD dyno and produced numbers in the 276whp and 282wtq range. From what I know, those are within the "known" range against say a Dynojet AWD dyno.

The car pulls strong and very smooth. I have a slight part throttle stumble that I am pretty sure the culprit is in the timing.

As for using some 272's, the Evo Viii guys use them all the time. Some complain of the idle and lack of vacuum. This causes a stall on decel on occasions. To combat this the idle is raised to 1k rpm, but then the engine sounds high and you can't hear it loping. Our shop Evo Viii is running the 264's and making over 350whp on them and a stock intake plenum. Personally, if you have a daily driver.....find a set of 264's.


Jose
Japtrix.com

Ok since nobody has given finite numbers then I will. The first time I built my motor, I used OEM 2.5L Sti head gaskets. This gave me a compression ratio of about 9.17:1(according to Ron at Axis power racing). The car, using a VF22 and Sti-Ra gears pulled a strong 305whp/303wtq on a Dynojet AWD in Miami. I bested a 12.8@109mph at MOROSO.
I got greedy with boost and well, blew #2 and #4 ringlands. SO, I rebuilt my motor. This time using COMETIC head gaskets and ARP head studs. Again using the help of Ron he suggested that I use the .051" thick gaskets. This would put me at a decent 8.5:1 compression ratio.

I recently dynoed my car on our Mustang AWD dyno and produced numbers in the 276whp and 282wtq range. From what I know, those are within the "known" range against say a Dynojet AWD dyno.

The car pulls strong and very smooth. I have a slight part throttle stumble that I am pretty sure the culprit is in the timing.

As for using some 272's, the Evo Viii guys use them all the time. Some complain of the idle and lack of vacuum. This causes a stall on decel on occasions. To combat this the idle is raised to 1k rpm, but then the engine sounds high and you can't hear it loping. Our shop Evo Viii is running the 264's and making over 350whp on them and a stock intake plenum. Personally, if you have a daily driver.....find a set of 264's.


Jose
Japtrix.com


whats greedy with boost?were you pushing more than 22 or 23 psi? also thicker gaskets will off set your timing gears a little bit 9.17 seems a little steep. not doubting you just suprised at the difference. did ron show numbers to verify it?

From what I found the revised rs head gasket is .054 thick and the STI gasket is .021. They are made of the same material. The compressed size will be slightly less than the cometics but more than the sti. The compression ratio should be around 8.3.

http://forums.nasioc.com/forums/showthread.php?t=630797&highlight=head+gasket+thickness

They are $30 a piece and have held up fine for me for 2 years running up to 26lbs. Pistons will be your problem before your head gaskets.

FWIW.
I'm running a stock 257 w/ 207 heads w/ stock gaskets. I am supposed to be closer to 9:1 from the stock 8.2:1.
Higher compression, yes.
Less ability to make big power..prolly.
Added ability to have off throttle power, yes.

You check out SM? Ask Eric what he thought? What cams did you decide. Because your static compression is gonna raise, but once you get moving...if your running a 272, won't your compression change?
Higher gas comsumption...prolly.

FWIW.
I'm running a stock 257 w/ 207 heads w/ stock gaskets. I am supposed to be closer to 9:1 from the stock 8.2:1.
Higher compression, yes.
Less ability to make big power..prolly.
Added ability to have off throttle power, yes.

You check out SM? Ask Eric what he thought? What cams did you decide. Because your static compression is gonna raise, but once you get moving...if your running a 272, won't your compression change?
Higher gas comsumption...prolly.

i am going 264's i wimped out on the 272's read to many nasioc threads on vacuum/brake issues.and i did not want to jack my idle up to compensate :( when i built standard gas motors cams never effected compression. they effect valve opening ,and closing duration to allow for more air fuel. as for the power i should make a little more power with less boost and timing with the higher compression,but it needs to be tuned to reap the benefits of higher compression.

Well its gonna need to be tuned either way. ;)

I really wouldn't call going 264 wimping out btw :D (what manufacture did you go with?)

Are 264's comparable to the Crower Stage II cams?

Are 264's comparable to the Crower Stage II cams?

yes they are,but good luck finding em. i don't think thay are going to make them anymore. i looked very hard for them ,and even called crower they said 264's were on hold . 272's were all over the place

Well its gonna need to be tuned either way. ;)

I really wouldn't call going 264 wimping out btw :D (what manufacture did you go with?)


the only ones that were available were the helix 264's they are new billet ground cams not stock weld and regrinds. they look to be as good as everyone elses and come with dual springs,and titanium retainers

Ha.. I've got the Stage II cams in my car now. I suck 'cause I have an automatic transmission so my DynoJet numbers look like ass. BUT.. with an Axis 2.5litre, 20g, EWG, heavily ported heads, and those cams I made 35 less WHP than my tuner's STi with a Green. But I made almost 100 ftlbs. of turque less.. but it stayed rock solid steady at 290ft-lbs all the way to redline.

350whp and 290torque.

what are the actual specs on those cams. Crower Stage II cams are 220 duration at .050" and .400" lift. Quite a bit more than the stock STi or WRX cams.

Ha.. I've got the Stage II cams in my car now. I suck 'cause I have an automatic transmission so my DynoJet numbers look like ass. BUT.. with an Axis 2.5litre, 20g, EWG, heavily ported heads, and those cams I made 35 less WHP than my tuner's STi with a Green. But I made almost 100 ftlbs. of turque less.. but it stayed rock solid steady at 290ft-lbs all the way to redline.

350whp and 290torque.


wow your tq took a poop on ya.why? i mean i would have expected more torque. i made 303 tq on stock 2.0l block and heads. is this becuase you are automatic?

i should say that is very nice h.p just hope my torque is around my hp that is all :)

torque converter... But launching it must be a beast :devil:

Sonic, yes 22psi to be exact. I broke the ringlands. Reason I went with the gaskets is because it was cheaper, and quicker for me to get the car back running this way. Otherwise I would have taken the block apart, ordered a set of Weisco's and put it back together.

Still, she runs like a champ. Oh, did I mention I'm on USDM Sti cams. Don't think I did.

Jose

hey jose

who tuned the motor? i have seen people run high boost with the stock sti motor. you were a 2.5l sti with 2.0l heads right? i guess that would make a difference :( one last question what year was the 2.5l,and did they change anything with pistons from 04-06? jsut trying to get as much info as i can. i know the higher compression will make more power with less boost and timing reducing pressure on the pistons. :)


vince

You are correct, 2.5l Sti block on 2.0l WRX heads using 2.5l Sti cams. Originally, one of the guys tuned it who used to be on the board. He's since moved to France. It was a good tune except there were some areas that still needed help.
Of course, since I changed the compression I had to re-tune.
The motor is '04 USDM Sti. I'm not sure what if any changes were made to the pistons. I'll tell you this, I used WRX wristpins in my motor this time around after reading a detailed writeup on APS' website. They say that they are stronger. I had a spare set lying around, so I used them. No side effects that I can tell.

Adding duration reduces torque.. there's no way around it. But you add plenty of HP and do a better job of maintaining whatever torque you're making.

it reduces torque,but shoud it reduce to under 300 ftlbs of torque? i was over 320 awhp,and was at 303 awtq on my usdm 2.0l motor. i would think on the same dyno the torque will be around or more than the hp. i like hp but torque moves the car :)


pacobeagle
so you are saying the sti wrist pins are also a weak spot? could you post a link to the aps article? please :) pretty please ;) ok enough don't make me beg :p i would like to read the article. i layed in bed last night thinking about forged pistons ,cost and my naked wife :eek: ,and pistons took over my thoughts. that i how much this stuff is on my mind :lol: i need to decide what i am looking to do,and i need to make a decision with in a week or so as the car gets transformed then,and i would like to do it before things get put back together.

it reduces torque,but shoud it reduce to under 300 ftlbs of torque? i was over 320 awhp,and was at 303 awtq on my usdm 2.0l motor. i would think on the same dyno the torque will be around or more than the hp. i like hp but torque moves the car :)

Increase duration - HP goes up, TQ goes down.. period. Your torque won't look as bad as mine, the automatic eats up a lot of power - probably close to 50whp since my torque converter is pretty loose. I think a bone stock AT makes 30whp less than the 5mt. You know how those stock block STi's all make the same whp and tq? Slap cams in those cars and the hp/tq will no longer be the same.

i can dig it . just in denial :) i am so happy i 5mt although my wife is a better manual driver. she can rip a better e.t than me her reaction time is way quicker than mine :eek: .

Read about piston "squish" or "quench" effect before you use increase head gasket thickness to lower CR. In someways you trading one source of denotation for another.

Read about piston "squish" or "quench" effect before you use increase head gasket thickness to lower CR. In someways you trading one source of denotation for another.

i talked to my tuner ,and he has tuned,and his shop has put together several 2.5l motors with wrx heads,and just used the stock gaskets,and they just tune for it. he told me i will get more power with less boost ,and less timing :) that is the route i am going. i think it is the lesser of the 2 evils :)

Make sure to get a few gallons of crappy winter gas in the tank...just to be safe when next winter rolls around. :)

Not to mention, working on something the tuner is familar with is a big bonus ;) :p

thanks for the advice :p ya bastage.j/k i have to get rid of the gas that is in the tank now :( i will pump in it in to the other car. it is about 3 weeks old now. i am hoping the dealer has thier insurance agent in to look at my car this week. i am getting a little pi$$ed.

sonic....I would like to compare maps(if you are using UTEC). Just out of curiosity of course.

Oh, and link to APS wristpin.....
http://www.airpowersystems.com.au/us_spec/subaru/sti/pistons/pistons.htm


Jose

sonic....I would like to compare maps(if you are using UTEC). Just out of curiosity of course.

Oh, and link to APS wristpin.....
http://www.airpowersystems.com.au/us_spec/subaru/sti/pistons/pistons.htm


Jose

Jose
i am not installed yet. it will be a couple of weeks . i am dealing with a dealer error with my 2.0l they did not tighten the oil filter down enough after an oil change,and i lost my oil. so they are having an insurance adjuster look at the car,and after that the motor is going to be done. i am using ecutek by the way. sorry. if i did use the utec i would definetly compare maps :) thanks for the link by the way :)


vince

Vince, not a problem. The oil filter thing.....that can happen to anyone. I did it on Sat. night!!!! I started the car on Sunday to go to an autox and as I am pulling out of the drveway I see a long line of oil. SO, halfway into the street and the other half still on the driveway I jacked up the car. Turns out the old oil filter gasket got stuck to the oil filter housing(cooler). Luckily I only lost about 1/2 quart. I topped it back up and off I went to the autox. Got 1st in SM and only .9sec of FTD. Sweet.

Anyhow, if you were anywhere near the West Palm Beach, Fl area you are more than welcome to take my car for a spin.

Jose

i am in illinois :( . i would have loved to take the car for a spin :) the oil filter took about a 150 miles and it came loose in traffic doing 55 i was in the center of three lanes in rush hour oil pressure dropped instantly ,and oil was everywhere. the car started knocking i pullled over almost instantly.i had cars all around me and cut some off to pull over,but it was to late.the filter was like 3 1/2 to 4 twists back from the block. i just made this a short story . i could go into alot of detail but it would be huge :) anyways how is this motor holding up?

well i broke down and went forged 2.5l:D no more worries :banana: now it is how much power do i want make;) this is all your fault jose :lol:

what heads then?

what heads then?

pnp wrx heads,an put my 264 cams in em :) for right now i think those will be fine :)

Why did you go forged when only shooting for sub 400whp?
Granted its less rotating weight and added durability, but your heads will be a limiter in power down the line, not to mention the tranny ;)

My fault.....how do you figure? I'm glad that you decided to go this way. You won't be sorry. As for the heads, pnp is better than stock. Either way, you'll make decent power for sure. Let me add, reliable power without having to "take it to the limit" so to speak.
The tranny can be a factor if you dirve like a nut.
Please keep us posted. I want to know what you make in power.

Jose

Why did you go forged when only shooting for sub 400whp?
Granted its less rotating weight and added durability, but your heads will be a limiter in power down the line, not to mention the tranny ;)

doctornick
i have seen threads where the usdm wrx out flowed jdm heads when pnp was done. as for sub 400 well that is my goal as of right now,but as you know never a long term thing ;) so now it is done ,and when i go bigger i can without having to worry about the motor as much :)

pacobeagle1

i will keep ya posted,and thanks for the advice. i had to blame someone for the extra spending :p

Before you decide to do this hybrid, I found an alternative that you may be interested in.

Most people who get 2.5l hybrid's complain of the cams or heads or both. Mostly the cams. The cost of getting STI cams and an sti shortblock is the same price if you just bought a complete sti shortblock and sold your wrx shortblock complete.

This is of course assuming your shortblock you have now is in working condition. Just and idea.
Copy that. I put in a stage #2 - 2.5 with stock heads. I've spent way more money trying to figure out why it wont mak whp at $250 per hour of dyno time. The solution after 1,200$ is the wrx heads don't work with a 2.5 sb. Wish I would have done the heads while I had the engine out, to begin with.
wrx heads are bad ju ju for the 2.5 anyway. Do it right now and save a lot of money.

Copy that. I put in a stage #2 - 2.5 with stock heads. I've spent way more money trying to figure out why it wont mak whp at $250 per hour of dyno time. The solution after 1,200$ is the wrx heads don't work with a 2.5 sb. Wish I would have done the heads while I had the engine out, to begin with.
wrx heads are bad ju ju for the 2.5 anyway. Do it right now and save a lot of money.

i got some 264 cams for the heads. i did some searching,and found some threads on thi setup.

Copy that. I put in a stage #2 - 2.5 with stock heads. I've spent way more money trying to figure out why it wont mak whp at $250 per hour of dyno time. The solution after 1,200$ is the wrx heads don't work with a 2.5 sb. Wish I would have done the heads while I had the engine out, to begin with.
wrx heads are bad ju ju for the 2.5 anyway. Do it right now and save a lot of money.

We're of the same opinion; running the stock WRX heads with the 2.5L SB doesn't yield a whole lot more power but it does yield a much fatter midrange torque band. We've installed and tuned the Helix 264s w/ valve train in the WRX heads on a 2.5L SB more than a couple times now and have been very impressed with the results. I wouldn't say that these cams make the WRX heads equivalent to the STi heads (since the AVCS makes a lot of midrange power and torque) but from our results, it appears that these cams make the WRX heads capable of having higher peak airflow. For the price, they're an excellent option that lets you use your WRX heads and still optimize the 2.5L block. As for gasket thickness, we use the .051 for this hybrid.

Thanks,

Geoff

Strongly suggest factory 2.5 STI headgaskets, and a correctly designed piston that has a corrected dish volume for the WRX heads.
Thicker headgaskets will lower compression, but also will play with cam timing.

We're of the same opinion; running the stock WRX heads with the 2.5L SB doesn't yield a whole lot more power but it does yield a much fatter midrange torque band. We've installed and tuned the Helix 264s w/ valve train in the WRX heads on a 2.5L SB more than a couple times now and have been very impressed with the results. I wouldn't say that these cams make the WRX heads equivalent to the STi heads (since the AVCS makes a lot of midrange power and torque) but from our results, it appears that these cams make the WRX heads capable of having higher peak airflow. For the price, they're an excellent option that lets you use your WRX heads and still optimize the 2.5L block. As for gasket thickness, we use the .051 for this hybrid.

Thanks,

GeoffNo-one told me this when I did my conversion about 1-1/2 yrs ago. In fact pdx said the wrx heads would be fine, Now $2,000 I wish I would have done the heads or cams when the engine was out.

By the way the Roos six speed tranny I got from you guys [with - No diff slip] is a kick. Thx Max And yes the low end torque [ from the 2.5 sb] coming out of corners is very strong. As in being able to get the front end light at 3,000 rpm. Which is fun.

But definetly do the cams / sti, or = heads while the engine is out the first time. paita to go in and redo things.

So, in my case, what do the USDM Sti cams equate to? 264's??

So, in my case, what do the USDM Sti cams equate to? 264's??

no they are not that aggressive. not saying that 264's are aggressive ,but they have a bit more lift than sti's cams :)

ARGH!!! The USDM STi cams have the indentical duration as the WRX cams.. but the STi cams have slightly more lift. They're not even close to a "264" cam - which has around 12 degrees more duration.

ARGH!!! The USDM STi cams have the indentical duration as the WRX cams.. but the STi cams have slightly more lift. They're not even close to a "264" cam - which has around 12 degrees more duration.

wow i did not know there was 12 degrees more duration with the 264's. that is a huge difference :eek:

No-one told me this when I did my conversion about 1-1/2 yrs ago. In fact pdx said the wrx heads would be fine, Now $2,000 I wish I would have done the heads or cams when the engine was out.

By the way the Roos six speed tranny I got from you guys [with - No diff slip] is a kick. Thx Max And yes the low end torque [ from the 2.5 sb] coming out of corners is very strong. As in being able to get the front end light at 3,000 rpm. Which is fun.

But definetly do the cams / sti, or = heads while the engine is out the first time. paita to go in and redo things.

And depending on the ECU you're using or EM you're using, the STI heads allow you to have AVCS.

wow i did not know there was 12 degrees more duration with the 264's. that is a huge difference :eek:

That's for the Crower Stage II cams - which I believe they consider "264". I made great WHP but lousy torque with the 20g.. right now the car is at Xotic Motorsports with the SZ55 and meth injection - it should be on the rollers by Monday.

Big MAF??

Ok since nobody has given finite numbers then I will. The first time I built my motor, I used OEM 2.5L Sti head gaskets. This gave me a compression ratio of about 9.17:1(according to Ron at Axis power racing). The car, using a VF22 and Sti-Ra gears pulled a strong 305whp/303wtq on a Dynojet AWD in Miami. I bested a 12.8@109mph at MOROSO.
I got greedy with boost and well, blew #2 and #4 ringlands. SO, I rebuilt my motor. This time using COMETIC head gaskets and ARP head studs. Again using the help of Ron he suggested that I use the .051" thick gaskets. This would put me at a decent 8.5:1 compression ratio.

I recently dynoed my car on our Mustang AWD dyno and produced numbers in the 276whp and 282wtq range. From what I know, those are within the "known" range against say a Dynojet AWD dyno.

The car pulls strong and very smooth. I have a slight part throttle stumble that I am pretty sure the culprit is in the timing.

As for using some 272's, the Evo Viii guys use them all the time. Some complain of the idle and lack of vacuum. This causes a stall on decel on occasions. To combat this the idle is raised to 1k rpm, but then the engine sounds high and you can't hear it loping. Our shop Evo Viii is running the 264's and making over 350whp on them and a stock intake plenum. Personally, if you have a daily driver.....find a set of 264's.


Jose
Japtrix.com

Sorry to dig up an old thread but was this on the OEM STI block with WRX heads? Was there any milling of the heads involved?

Sorry to dig up an old thread but was this on the OEM STI block with WRX heads? Was there any milling of the heads involved?

The WRX heads will go right on to the STI block with the right gasket (without milling). If you are thinking STI cams -> WRX heads, there's A LOT of custom work to make that happen pretty much making it not worth it (you'd be better off even buying the pricey JUN 264 or 272's).

Cheers,

Gary
Gruppe-S

Is there a set of cams that are PnP (i.e., not the STI cams) for the WRX heads that only increase lift, not duration? Wouldn't you get the advantages of better high-end airflow without the loss of low-end TQ? Man, I can't believe someone hasn't capitalized on this.

I have been wondering about a 2.5 as well but also question how smog legal I can get away with before going to far that I no longer can pass smog, if there is some need. Specially if I get poped for smog ref vs just a few bolt ons. I see most of you are more east the west coast. Maybe you guys can help me out with these questions. :confused:

Is there a set of cams that are PnP (i.e., not the STI cams) for the WRX heads that only increase lift, not duration? Wouldn't you get the advantages of better high-end airflow without the loss of low-end TQ? Man, I can't believe someone hasn't capitalized on this.

Companies like Kelford can sometimes mill a cam to your specs.. Crower may be able to, also. But the Crower stage I cams (don't know if they ever made any but they used to list the specs) increased the lift quite a bit and only increased the duration a tad.

BUT - increasing ONLY the lift won't help nearly as much as increasing the duration.

Yes, the V7 JDM STI cams would increase lift but not duration over the WRX cams. In fact as I recall the V7 cams have less duration than the USDM WRX cams.

My personal opinion is if you're looking for something along those lines the JUN 256 cams would be better suited for your application as those cams offer better midrange. The cams (which do not require valvetrain) are $999/set.

Cheers,

Gary
Gruppe-S

http://forums.nasioc.com/forums/showthread.php?t=419230

Some of this thread gets REALLY technical.. Adrian gets pretty deep into it.

So: starting with a STi short block (assuming I bought one direct from the dealer, and didn't build it myself; ) with the goal of maximixing TORQUE across the powerband as much as possible; what do you all recommend for heads/headgaskets/cams?

Final application to be 90% DD, max 10% motorsports.

Not worried about high end HP... then I'd use the stock STI stock block with the 9:1 CR, which will give you silly TQ and fantastic off-boost throttle response. Use the stock STI head gasket. If you want to go down in CR a little, then use a slightly thicker (0.051") cometic gasket, but that will hurt your off-boost performance. Stick with the stock cams if you're not concerned about HP. This car will be a TQ monster. If you want higher HP, go with crower stage 2 cams but prepared to spent a wad on those.

We are selling used EJ257 heads for under a thousand including the cam position adapter, if you already have the 2.5 short block I recommend going with the 2.5 heads. They flow better, won't mess up the compression or quench area, and have better heads and valvetrain (and oh yeah the STI cams are substantially lighter).

If you want to upgrade them with Cosworth cams and/or Helix valvetrain we can do that for you also, but it starts getting pricey from that point forward.

If you want a WRX head to flow as well as an STI head you'll have to do some porting and valve work, as well as a set of more aggressive cams. I also do have some V8 big port heads being sent back to us next week but they are pricey as well.

Cheers,

Gary
Gruppe-S

Gary with those EJ257 heads would you not also need an ECU to run the AVCS? Then engine management to match that ECU vs what you currently have. I ask because I currently have the 03 WRX with AP and ST. I am putting in a 2.5 block but still exploring head and cam ideas. If I went with the 2.5 heads I would also need a new ECU as well as new AP and ST to run the avcs correct? If you do not use the new ECU wouldn't the cams be 5 degrees retarded without the AVCS hooked up?

Couldn't you simply tune around that by advancing the timing maps 5 degrees across the board?

Gary with those EJ257 heads would you not also need an ECU to run the AVCS? Then engine management to match that ECU vs what you currently have. I ask because I currently have the 03 WRX with AP and ST. I am putting in a 2.5 block but still exploring head and cam ideas. If I went with the 2.5 heads I would also need a new ECU as well as new AP and ST to run the avcs correct? If you do not use the new ECU wouldn't the cams be 5 degrees retarded without the AVCS hooked up?

For the EJ257 heads, if you wanted to run AVCS you would need the sensors, the USDM harness, DBW throttle body, ECU, pedal box, and a few other things. The reason being that the EJ257 uses the 3 wire reverse hall-effect sensor whereas the JDM EJ207 (non-DBW) uses the 2 wire hall-effect cam position sensors.

IMO while AVCS is nice to have, it's not worth it to try to convert to AVCS unless you already have the parts and time to spend doing the wiring / installation.

Cheers,

Gary
Gruppe-S

We are selling used EJ257 heads for under a thousand including the cam position adapter, if you already have the 2.5 short block I recommend going with the 2.5 heads. They flow better, won't mess up the compression or quench area, and have better heads and valvetrain (and oh yeah the STI cams are substantially lighter).

If you want to upgrade them with Cosworth cams and/or Helix valvetrain we can do that for you also, but it starts getting pricey from that point forward.

If you want a WRX head to flow as well as an STI head you'll have to do some porting and valve work, as well as a set of more aggressive cams. I also do have some V8 big port heads being sent back to us next week but they are pricey as well.

Cheers,

Gary
Gruppe-S

Ok well what exactly are you talking about in this post...can you use the heads without the AVCS and not experience the 5 degrees of retard from the cams?

Ok well what exactly are you talking about in this post...can you use the heads without the AVCS and not experience the 5 degrees of retard from the cams?

Yes, the USDM STI heads / cams, etc can be run on a WRX ECU (using our cam position sensor bracket) but would need to be professionally tuned (sorry I've had too many redbulls today). :D

Cheers,

Gary
Gruppe-S

My engergy drink of choice is AMP but I know how ya feel! Sounds like this could be a GREAT option for my swap! Have you had many using this option? Any dyno charts you can point to using this setup?

Drink Redbull. They sponsor rally teams.

My engergy drink of choice is AMP but I know how ya feel! Sounds like this could be a GREAT option for my swap! Have you had many using this option? Any dyno charts you can point to using this setup?

Yes we've done quite a few of these swaps. We just got the latest AWD Mustangdyne in here and new software - I'm still figuring out how to get the old dyno graphs into the new dyno software....

That said you'll do about what a 2004+ STI will do, except the WRX intake manifold and t-body is a bit smaller, so the difference is usually about 5whp + 10ft/lbs on the table (and not being able control AVCS) compared to a true STI 2.5. But overall the midrange and top end power is substantially improved over a 2.0 car, it's definitely a bang for the buck swap in my opinion.

Cheers,

Gary
Gruppe-S

If you want a WRX head to flow as well as an STI head you'll have to do some porting and valve work, as well as a set of more aggressive cams. I also do have some V8 big port heads being sent back to us next week but they are pricey as well.

Cheers,

Gary
Gruppe-S

I've always heard that the USDM STi and USDM WRX heads only differ in the combustion chamber - otherwise they're identical port wise.

And the same went for the intake manifolds.

My build is complete, so I thought I'd chime in...

My build was in steps. This is the order of my build

EJ205 w/ stock turbo

EJ257 longblock with the stock WRX turbo (no avcs)

Ej257 longblock w/ stock WRX turbo (w/ AVCS)

EJ257 longblock w/ Element GT52 turbo (W/AVCs)

Not custom tuned, but Phil had a base map for the setup (running a Hydra).

Gary, I know you said you didn't think AVCS was worth it. I can't disagree more. The difference in response/torque with the avcs was more dramatic than the 2.5l swap. The difference from the ej205 to ej257 w/out avcs was broader torque curve, but not as impressive as I hoped. The integration of AVCS was HUGE for me.

Now, I know STI cams aren't much more aggressive than WRX cams, but stock STI heads/cams are still good for 500whp(maybe 450whp on Gruppe-s mustang dyno). If your power goals are at this number or less, and you care about having a fat, broad torque band with good response, I'll tell you that the 2.5l w/ AVCS is not something you should pass.

I took the advice of my tuner (Phil Grabow) that AVCS is more valuable than people take it for. Instead of spending $700-$1000 on non-avcs cams, I sourced some used STi heads for $800. Of course, a Hydra is more than an AP or UTEC, but that's another story. The Hydra controls the AVCS.

There's no doubt that if you want near 400whp or more, you HAVE to either upgrade your cams on a Hybrid or run STI heads. Since my goal was 450whp on pump + water injection, I knew the STI heads would be fine.

Here's how I calculated the build.

STi shortblock $1600
Upgraded cams + retainers+ springs $1000
Sell used EJ20 shortblock -$200

Sti longblock $2400
Hydra $1500
Sell used complete EJ20 longblock -$1500


I knew the AVCS route, though it looked cheaper, relied much more on getting much more money for the longblock vs. the shortblock when I sold my used parts. However, it worked out just as I planned. The price of the AVCS setup is still a little more since you have to pay for the labor of AVCS, but the wiring up for AVCS on a Hydra isn't nearly as extensive as getting a STI ecu and wiring that+ switching to a STI Engine management system.

After contemplating MANY options, I went this route per my tuner's request. Even though it wasn't as economical doing it in stages, I'm really glad I had the chance to experience the 2.5l with no avcs, then with. The difference of the 2.5l with no avcs was very marginal. In fact, I'd argue that the 2.5l with a very aggressive cam may not feel any more responsive than 2.0l with stock cams.

The idea of having a motor with similar bottom end as an EJ20 but with much more top-end is nice, but for me, the swap was to fatten the torque curve all over. The 2.5l alone didn't do it, but w/ the avcs, I was a happy camper.

Sorry for the long rant. This experience, I believe, isn't shared by many. Most people don't get to experience these changes separately in stages.

I think the route you went probably makes the best all around daily driver. Once you start porting heads and swapping cams you start losing what makes a car "friendly" to drive on the street - off idle power. Conversly, cams and headwork can make a medium sized turbo cut large turbo times at the track.. but not so much fun DRIVING to the track.

Good info Keanie. For my daily driver I am going with a lower CR (8.2:1) and stock 2.0 heads. Conservative for pump gas (can play with boost and turbo combos a bit), good throttle response due to stock cams. I'm also sticking with a smallish turbo (VF39) for good spool. Doing TGV deletes as well to improve throttle response. Given I currenntly have no desire to go above 300 WHP,I think this will suffice. Besides, given too high rpm caused me to ruin my first engine, I have no desire to wind this one out a whole lot. I'm fine with revving to 5500-6000 rpm and leaving it at that. But for big power, cams and even AVCS would definitely be a must. If I decide to go for big power (would mean full tranny swap also), I would go with camms but given what I already have into this 5 yr old well-used car, I see no reason to do that. The early USDM WRX's just simply arent worth it. I'd sooner get an STI that is built for bigger power out of the box.

The setup I have is good for a daily driver and for track. Phil was using this setup for his new time attack sti, and did really well. He said it was nice not always having to shift and let the torque pull him through.

Its especially good for my setup because I have a 5mt, so the broad power with fast response goes really well with the tall gears.

Hi keaniegenie, no doubt the AVCS system is good and definitely results in positive improvements in the power curve. It's just my opinion that for the added cost of adding AVCS perhaps isn't the best power for the dollar option. That said your setup sounds awesome and seems like it's working for you :)

Thanks,

Gary
Gruppe-S

And the bad part is going Hydra is additional expense. It is too bad there is not some sort of AVCS controller that could be added to the Wrx for a reasonable price. Having searched through lots of threads, I have not found a definitive way that it can be controlled with a WRX ecu from stateside. Since I have a 02 WRX and already have both AP and Street Tuner, it would be an expensive change over.

We are selling used EJ257 heads for under a thousand including the cam position adapter, if you already have the 2.5 short block I recommend going with the 2.5 heads. They flow better, won't mess up the compression or quench area, and have better heads and valvetrain (and oh yeah the STI cams are substantially lighter).

If you want a WRX head to flow as well as an STI head you'll have to do some porting and valve work, as well as a set of more aggressive cams. I also do have some V8 big port heads being sent back to us next week but they are pricey as well.

Cheers,

Gary
Gruppe-S

What the?!? Half a dozen posts back you're selling USDM AVCS heads and saying they're the best bang for the buck.. did I miss something?

And the bad part is going Hydra is additional expense. It is too bad there is not some sort of AVCS controller that could be added to the Wrx for a reasonable price. Having searched through lots of threads, I have not found a definitive way that it can be controlled with a WRX ecu from stateside. Since I have a 02 WRX and already have both AP and Street Tuner, it would be an expensive change over.

Did you read my whole post? The AVCS did more to help broaden the power band than the shortblock alone.

The only time I can see not getting a Hydra and using AVCS on a build is if you're building a top-end only monster, or you're going as cheap as possible, ie shortblock + WRX heads + STI cams.

I was advised to avoid the STI cams unless you are looking to go over 350WHP or rev to 7500rpm, both of which I am not looking to do.

I was advised to avoid the STI cams unless you are looking to go over 350WHP or rev to 7500rpm, both of which I am not looking to do.

If you're looking to go under 350whp, then I'd agree. That said, go drive some cars before you make that decision.

The 2.5l swap alone wasn't much of an upgrade IMO. The torque difference was minimal.

Did you read my whole post? The AVCS did more to help broaden the power band than the shortblock alone.

The only time I can see not getting a Hydra and using AVCS on a build is if you're building a top-end only monster, or you're going as cheap as possible, ie shortblock + WRX heads + STI cams.

Yeah read your post. Entirely. Or if you don't want to spend the extra $1600 and ditch your current method of tuning, your current ECU, Etc. It would be so nice if someone just made an AVCS Controller! Something stand alone that is based on TPS and RPM's seems would work. I mean the honda guys have had v-tec controllers for a while now. Seems we would catch up. There was some mention of Gruppe-S selling such a device in a couple posts, but I have not been able to find it anywhere. Maybe it did not work out.

The 2.5l swap alone wasn't much of an upgrade IMO. The torque difference was minimal.

Maybe by the seat of the pants terms but the numbers indicate a substantial difference. 50-60WTQ is not insignificant. Maybe some day if I get more greedy, I'll sell the car and get an STI. I just can't justify putting any more money into a WRX. Heck, if I do everything I "sould do" I'll be close to STI costs (maybe over) and still not have STI tranny, diffs, clutch, axles, seats, avcs... the list goes on and on.

heck we had a guy that tuned with a stock turbo and he was then producing 300 wtq after tuning it and the previous best on the old wrx was 220 wtq....80 wtq gain! Does not sound insubstantial to me either. If you can't feel that....something seriously wrong with your butt dyno.

I've got about 350whp untuned on a stock 04 5mt. Not PPG.

After seeing that in another forum...I am starting to lose any faith in this guy...

After seeing that in another forum...I am starting to lose any faith in this guy...

Why, because it's untuned? Phil sent me a base map for my setup to get me going. Anybody with a Hydra knows that the base maps Phil sends are a million times better than the base maps that Cobb sends people for just a turboback exhaust.

This is what I get for trying to help the community...

heck we had a guy that swapped it out with a stock turbo and he was then producing 300 wtq after tuning it and the previous best on the wrx was 220 wtq....80 wtq gain! Does not sound insubstantial to me either. If you can't feel that....something seriously wrong with your butt dyno.

You want me to believe that you put a stock WRX turbo on a 2.5l and hit 300+wheel torque without boost creep? I think your the one with the credibilit issues.

I appreciate what you are trying to accomplish Keniegenie... explain that you noticed a definitive improvement in TQ with AVCS. I don't doubt you one bit and thank you very much for that piece of info. All info/opinions are good and helps. Thing is, everyone has different goals. For example, when I ask about turbos... everyone says... 20g!! But, I personally feel a 20g will spool way too slow for my liking. One of the main reasons I am going to a 2.5 is for better around-town driveability (i.e., more displacement). I don't want to lose what I gained just so I can say I made 350 or 400WHP. I totally agree that if you have a larger turbo you probably didn't notice a whole lot on the bottom end. Of course, AVCS would help out immensely in that regard with a larger turbo. That being said, the folks who only mildly upgrade their turbo (or not at all) should notice a huge difference in spool-up and general off-boost TQ availability.

I appreciate what you are trying to accomplish Keniegenie... explain that you noticed a definitive improvement in TQ with AVCS. I don't doubt you one bit and thank you very much for that piece of info. All info/opinions are good and helps. Thing is, everyone has different goals. For example, when I ask about turbos... everyone says... 20g!! But, I personally feel a 20g will spool way too slow for my liking. One of the main reasons I am going to a 2.5 is for better around-town driveability (i.e., more displacement). I don't want to lose what I gained just so I can say I made 350 or 400WHP. I totally agree that if you have a larger turbo you probably didn't notice a whole lot on the bottom end. Of course, AVCS would help out immensely in that regard with a larger turbo. That being said, the folks who only mildly upgrade their turbo (or not at all) should notice a huge difference in spool-up and general off-boost TQ availability.

I think you and I are the same page.

Knowing how a 2.5l feels without avcs would definitely change the turbo choices for me. It's funny you mentioned the 20g thing, because I think a 20g is too laggy for a 2.5l hybrid daily driver.

The best way I can describe the difference is AVCS seems to fill the torque gap between boost offset to boost onset. Power is MUCH more linear, and the power band is smoother. On your stock 2.0, you'll notice the power is either off or on. The 2.5l hybrid is the same, but the "on" power comes a little sooner, and the torque prior to boost onset is slightly more.

Hope that makes sense.

Why, because it's untuned? Phil sent me a base map for my setup to get me going. Anybody with a Hydra knows that the base maps Phil sends are a million times better than the base maps that Cobb sends people for just a turboback exhaust.

This is what I get for trying to help the community...

And now you have admitted that you lied....it was not untuned, it had a new map sent to you by Phil...that is tuning, not the stock ECU. While it may have been a custom OTS map, it was tuned, not stock.

You want me to believe that you put a stock WRX turbo on a 2.5l and hit 300+wheel torque without boost creep? I think your the one with the credibilit issues.

Nope I didn't do anything yet, but we did have a guy that did. He is located 300 wtq AFTER tuning. It is a 06 wrx with the 2.5 already in it and wrx heads up top. I thought the other guy got dynoed with his swap and the td04 but apparently he has not yet, and said he went with a VF-34 before getting dynoed. Not sure why this is so hard to believe, 06 wrx's are doing it every day. Here is the thread.

http://wrxatlanta.com/forums/showthread.php?t=9209&highlight=2.5+dyno

And now you have admitted that you lied....it was not untuned, it had a new map sent to you by Phil...that is tuning, not the stock ECU. While it may have been a custom OTS map, it was tuned, not stock.



Nope I didn't do anything yet, but we did have a guy that did. He is located 300 wtq AFTER tuning. It is a 06 wrx with the 2.5 already in it and wrx heads up top. Not sure why this is so hard to believe, 06 wrx's are doing it every day. Here is the thread.

http://wrxatlanta.com/forums/showthread.php?t=9209&highlight=2.5+dyno

You've gotta be kidding me.

A base map is fine, but it's not a custom tune. Custom tune means somebody tunes YOUR car. Every car's different. Ask any tuner. Two cars with identical mods is not going to run the same.

06 WRX's are NOT 2.5l hybrids. They have different heads and they also run AVCS from the factory. It's not the same as as people running 2.5l shortblocks with WRX heads.

So your telling me that a cobb stage 2 car is the same tune as the stock ECU.

So your telling me that a cobb stage 2 car is the same tune as the stock ECU.

Of course not, but when I say "untuned", I mean it's not custom tuned. How in the hell can I make a statement that I have roughly 350whp untuned if I'm not at least running a base map? My car is good for another 30-50whp just by Phil spending 2 hours in my car dinking with his laptop. If somebody says they have an Accessport and their car isn't tuned yet, it's pretty obvious they're saying they don't have a custom tune yet. Why in the hell would I put a $1500 engine management ecu in my car and not downloan a base map?

Nobody's dumb enough to claim HP gains with new mods without a map to run it. The post you talk about does not say I wasn't running a base map, it says "untuned", which in the sense of custom tuning, it's not. Don't assume I'm not at least running a base map. I have a Hydra. Anybody who knows a the smallest margin of knowledge about Hydra's knows that Phil sends his customers base maps, like Cobb sends base maps for their accessport and Turbo XS sends base maps for the UTEC.

Quit being a smart ass. If you want to learn something, then ask questions. I'm by no means a tuner, but it's obvious that I'm being questioned by somebody who knows a lot less than me.

I am not being a smart ass, just pointing out some inaccuracies as I see them. I think it is pretty tough to find someone with a stock turbo on a hybrid. Most people that do the hybrid swap are looking to make more hp and go with a decent turbo at the same time. So it is really hard to tell exactly just how much of a difference just the block itself makes. Me, I am planning on either doing a head swap or a cam swap at the same time as the block swap, so again, there will be no way to do a before and after with mine either. I personally have not seen a dyno just yet of just the block and nothing else. Hell, Unabomber is making 250's with the stock turbo on his 2.0 liter 2005 WRX...no AVCS that I know of. Why is it hard to believe that a 25% increase in displacement is yielding a 20% increase in power?

I will admit I know less about hydra on the Subaru market as I am pretty happy thus far with my current AP V1 with ST. I will be even more happy when ST advanced comes out and has most of the features of a pro-tuner. I have tuned a few cars, but this is my first WRX or Subaru for that matter. Previously I just messed with American muscle. But I am learning and doing it myself, not dumping cash for someone else to do something I am perfectly capable of doing myself. I will be doing the swap myself as well as a 6 speed tranny swap.

For the cost of going hydra and getting the AVCS to work....$1600 for me....I would be half way to my 6 speed swap....or a GT30R and injectors....or 2 decent nitrous setups.....or a super nice FMIC....1/3 the cost of a full PPG geared 5 speed...2 very nice water/meth kits which can also increase low end....lots of other options. For the money, I see better things spent in other places.

Check I-Speed's website, they have a dyno chart in their database of a Crawford S2 with only pinks and a tune. Still decent but power falls off after 5500 rpm, only because th eturbo can't keep going. I'm not sure why they didnt back off t'he boost though and run more timing. Would have been better power to redline.

Interesting...I ran a comparison of the 2.5 swap and the 2.5 06 with AVCS and it looked like they spooled the same time, but the 06 DID make 19 more torque (297 vs 278) but at 500 rpms later (2973 vs 3515 rpm). Both were stock turbos and with 91 octane crap gas. We get 93 over here on the east coast...probably good for a bit more there as well. Seems spool was the same...both spooled to 17 psi of boost. I imagine by turning it up a bit with better gas (compressor map on the stocker shows it is good to 21 psi at least in the mid range) the 2.5 probably could have made pretty close to 300 and the one with AVCS could have been well over 300. Soooo that said, 300 on the stocker with a 2.5 block and wrx heads seems VERY obtainable according to Clark's results...

Now hp...that is a totally different story. The td04 falls on it's face in the upper rpms's. I personally have not taken it over 15 psi at redline and that I think is pushing it quite a bit. Both cars topped out 233 and 236...so avcs made a 3 hp difference peak, but a little more area under the curve.

I love the comparisons he has on his site. It is just hard to find apples to apples sometimes.

We may have a very good chance here. One of the local tuners is (hopefully) going to run a Sti first with AVCS and then again with it unplugged to see the difference on the dyno. I hope he gets the time to do it!

Agreed. Oh, and I can get 94 here in Calgary but I dont dare tune for that ín case I'm away from town for an extended period. I don;t want to have to be stuck within 200kms of the city! :lol:

Yeah, we can get 100 and 106 here too, but it is cost prohibative for a daily driver...now water/meth injection (as cheap as $500 for a good kit)....108 octane to mix in with your 91 could help a LOT with det when running higher boost and or timing.

Honestly, I don't to mess around with that. I know it's simple and all, but honestly, I just want to be able to put fuel in the car again and drive.

Clark tuned a TD04 2.5l hybrid. He'll tell you that the biggest difference in that tune was the external wastegate.

My comments regarding AVCS are with direct experience. Before I made my decision to get STI heads (had a STI shortblock for months before I bought the heads) I heard from everybody and their mother whether or not AVCS was worth it. Honestly, most people said "that's a lot of money for a littlelow-end grunt". That said, isn't that what the 2.5l block is for too?

Here's the thing. The 2.5l block and the AVCS is designed to to get more power early in the power band. Discounting what AVCS does is no different than discounting what the 2.5l block does.

Even with AVCS, I don't expect the torque numbers for a 2.5l hybrid with a td04 to be too much different than a 06 WRX. Why? The turbo is so small, you'll have full boost before the AVCS even starts working in the taller gears, like 4th gear where people do their dyno runs. It will still help, but how much it helps is marginal.

Where the 2.5l block and AVCS really shine is when you run a bigger turbo. I can't believe how much better my torque PRIOR to boost onset. It almost feels like a 3.0 V6. What the car does after full boost in terms of power is usually more related to how much the heads flow and what turbo you run.

I maximized the td04 turbo before I even wired in the AVCS. If somebody wanted to run a td04 on a 2.5l block, I would say don't bother with the AVCS. However, if you're running a bigger turbo, such as a 20g or larger, the AVCS fills in the power gap between idle to boost onset. This gives the driving experience of less lag and a smoother, more linear power band.

This is part of the reason why I earlier said I wouldn't recommend anything bigger than a 8cm 18g on a 2.5l hybrid with big cams for a responsive daily driver. 2.5l STI longblock with AVCS, that's a different story.

Since thejean is looking to not break the 340whp mark, I agree with him that the AVCS isn't as important. You can get a very responsive turbo that barely hits that mark, and still have a very responsive setup. The smaller the turbo, the less you'll need the function of AVCS. Just like with engine displacement.

I'm sure for months on end, the benefits of AVCS will be discounted over and over again. When I talk to tuners and people who've had similar experiences as me, the answer is typically the same. You don't know how much it helps until you've got it or lost it.

I would go as far to say that if I had the option of running a 2.5l hybrid with upgraded cams vs. running a full JDM sti motor, I would have a very hard time making that decision. The JDM sti is a 2.0 block with very advanced AVCS, higher redline, forged pistons from the factory. Even though the hybrid as more displacement, I would think the bottom end torque between the two would be very similar since the higher lift cams on the Hybrid would take away some of the grunt of the 2.5l, and also since the JDM STI motor had AVCS and the hybrid would not.

I bet the dyno plots would not be that different.

^^^100% agree. Also, the JDM 2.0's are 9:1 CR (not sure which version).

And the bump of a full point is a lot of the difference also. Raising compression can make a car drive quite a bit different. But all of it is octane dependent. I am about to go take a ride in a guy's car who has a hybrid with a rotated setup and stock wrx cams. Look up the name Liquidforce on here and you can find some dynos. He made 417 off his hybrid with higher compression (around 9:1) and stock unported, uncammed heads on a 20g. He ran 12.33 at like 120 something mph in the quarter. THAT to me says he got some very decent results. That was also with a 6 speed and having to shift into high gears. http://forums.nasioc.com/forums/showthread.php?t=1107846

That was on the stock Sti short block also. But he roasted a couple pistons. Now he is on a forged piston block with a t3/t4 rotated set. Still on the WRX heads and cams. We have a dyno day coming up, so we'll see what he puts down.

That was on the stock Sti short block also. But he roasted a couple pistons.

Very important bit of info there. I was dead set on higher CR and to some point still am but you are playing with fire IMO.

He and the engine builder determined that it was probably due to them being hypereutectic pistons rather than forged, but decided to go with the revised 2.5 rs head gaskets (little thicker than the previous ones...older 2.5 rd gaskets that were THINNER than the Sti gaskets) as well as forged pistons. He has been running that setup since with no issues whatsoever. Did not get a chance to ride tonight due to work issues.

A hybrid with stock WRX cams that hits over 400whp must have been on a very friendly dyno.

His turbo wasn't rotated. Most STI's with the same turbo are at 340whp. The Meth helps, but should mostly increase the torque on a turbo that size.

Talk to Doug at Topspeed. If I remember right he was the one who tuned it. He has put out some fantastic cars. A stock Sti if I remember right reads around 220 at the wheels on his dyno. Heck write and ask him.

Talk to Doug at Topspeed. If I remember right he was the one who tuned it. He has put out some fantastic cars. A stock Sti if I remember right reads around 220 at the wheels on his dyno. Heck write and ask him.

Yes, and everyone knows the Top Speed dyno reads high. No knock on Doug, but it's a fact.

I did not realize that 220 was high for a stock Sti...oops I guess I was wrong, a stock Sti puts down around 240 on their dyno according to Doug.

I did not realize that 220 was high for a stock Sti...oops I guess I was wrong, a stock Sti puts down around 240 on their dyno according to Doug.

240 is what most stock STi's put down on a DynoJet.

So is this an abnormally high reading dyno? I mean I know it is no Mustang, but it seems pretty reasonable to me. If we figure the Sti at 300 at the crank and assume 20% drivetrain loss, that actually gives us 240 :) Seems like his dyno is fairly close. BTW I saw Liquidforce's car yesterday in person. It sounded very nice. He also has external wastegate on there. Not sure if this was done before on the 20g but it is on there not with the rotated setup. Next Saturday is the dyno day for our group. We will see what it puts down. I will check to see if the shop has a stock sti dyno to compare with his.