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Old 03-22-2009, 03:16 AM   #1
BAN SUVS
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Default 8000 RPM- minimum requirements?

So, I have an RS and I want to do an NA build and make it safely rev this high- though I expect to have the powerband actually fall between 3500-7500 or so.

I'm using an EJ257, but keeping stock EJ251 rods and getting custom pistons, probably from Wiseco. I'm going to see what I can do to keep the weight down on the pistons. Heads will be ported/polished, valvetrain upgrades from TWE included of course. Based on Matt Monson's discussions, stock fueling is fine with nothing more than increased octane and/or fuel pressure, though WRX greens in a '99 manifold would be easy as I have those parts in the garage.

Oiling is my biggest concern at the moment. Mostly because I feel I don't have a strong grasp on what the issues really are. An upgraded pump from an EJ207 should do the job, but the question is, what's the weakest link in the oiling system, and how do I correct it? I've read various conflicting things about what causes oil starvation, so my intention is to simply try to replicate the 207 oiling as that engine revs to 8000 stock. I believe there are minor differences between the Spec C crank and the EJ25 crank, but these should be things we can add, correct?

So if I have oiling taken care of, the valvetrain is good, and the rotating assembly won't fly apart, then comes cam profiling and tuning. With ~12:1 compression, I should be able to run 91 octane, but will go as high as straight 100 octane if it means more power. This is not a daily driver build, in case that wasn't obvious- purely track and autocross. I'll be using the usual bolt-ons- EL header, catless, 2.5" catback, Cobb intake, stock intake manifold (someday maybe some sort of custom plenum or even ITBs, but no budget for any of that now) so I'm sure DeltaCams can generate a good profile for what I want to do. The only thing left is tuning, which is probably going to be opensource on a 2005 RS ECU.

Any obvious things I'm missing? Note that I don't have specific power goals. The idea is to move the powerband up to a reasonable height and take better advantage of stock RS gearing. The actual power is going to be a function of proper cams and tuning I thnk, so it will be what it will be. I think 250 bhp @ 6500-7000 RPM is a reasonable expectation, and if things go right it could be as high as 280. I won't start going to the extremes of Zzyzx's race motor build though, so I expect to fall well short of 300bhp.
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Old 03-22-2009, 04:21 AM   #2
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The crankshaft and rod bearings are the weakest link I would think but thats coming from a forced induction standpoint. You've done your homework though so Im sure the motor gods will smile down on you when its all said and done. As for the oiling issue. I thought the 257s have oil squirters built in for the pistons???Another thing Id look into getting is a JDM STI oil pump. I had one installed when I got my motor rebuilt as I was told it runs higher oil pressure than US ones. Perhaps this is because the 207s are more high strung. Also try and find specs on JDM 207 valvetrain since theyre built for 8k redlines from the factory. G/L!!!
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Old 03-22-2009, 04:57 AM   #3
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There's quite a bit of discussion of high RPM oiling in the Built Motors Discussion forum. I won't claim to be even remotely close to an expert on any of it, but I've browsed through some of the threads. Take a look for the thread about cross-drilled crankshafts, and there are a couple/few big threads about oil pumps (9mm vs. 10mm vs. 12mm, shims and pressure relief settings, etc).

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Old 03-22-2009, 05:05 AM   #4
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why do u want to run to 8000rpm on an N/A car?
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Old 03-22-2009, 09:46 AM   #5
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This is not the thread to be asking that kind of question. It was anwered in the opening post....go back and read it again.
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why do u want to run to 8000rpm on an N/A car?
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Old 03-22-2009, 10:05 AM   #6
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Pat and jimmythagreek pretty much covered the important threads to look at as far as addressing the oiling issues at higher rpms, though I would also suggest looking into the newer dry-sump developments that are currently underway. I think your TWE valvetrain will be good, Delta can make the cams you'd need for that powerband, and I would think that with one of the larger oil pumps running, your motor would be okay sustaining that type of rev range. The return path for oil (in the heads) is pretty large already, but keeping oil around the pickup tube would have to be a high priority, through baffling, accusump or dry-sump.

I've read into the benefits of altering the chamfer on the oiling holes of the crank and agree that it is a good thing to look into doing right from the start.

All of the EJ20_ are DOHC, so you won't be able to directly transfer valvetrain stuff to your SOHC setup. TWE can provide the right springs and retainers for your goal, and the remainder of your intake plans appear to be solid. Don't write off ITBs just yet.....as the TGV housings can be reconfigured to function as ITBs with some work. There's been a bit of a resurgence in interest to that end lately....from both an NA and FI standpoint.

I don't know enough about opensource tuning to suggest that it would be the best way to go. Standalone EM systems have been proven to run well up into that rpm range and beyond.

Get the bottom end oiling planned out and the rest shouldn't be that difficult to build up. I would still be very careful of high sustained lateral g loading at rpms up over 7500 or so. That seems to be where many failures start to happen.

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Old 03-22-2009, 01:30 PM   #7
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Here We Go Again, Buy A Honda If You Want High Rev, its the reality.
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Old 03-22-2009, 02:47 PM   #8
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Here We Go Again, Buy A Honda If You Want High Rev, its the reality.
He can make his car a reality if he so desires.
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Old 03-22-2009, 04:05 PM   #9
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Originally Posted by Forester_007 View Post
Here We Go Again, Buy A Honda If You Want High Rev, its the reality.
Yeah, you're right. Even FHI never managed to make a Subaru engine rev that high reliably.


Oh wait, they did! The Version 7 Spec C revs over 8000 bone stock.
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Old 03-22-2009, 04:07 PM   #10
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Originally Posted by jimmythagreek View Post
The crankshaft and rod bearings are the weakest link I would think but thats coming from a forced induction standpoint. You've done your homework though so Im sure the motor gods will smile down on you when its all said and done. As for the oiling issue. I thought the 257s have oil squirters built in for the pistons???Another thing Id look into getting is a JDM STI oil pump. I had one installed when I got my motor rebuilt as I was told it runs higher oil pressure than US ones. Perhaps this is because the 207s are more high strung. Also try and find specs on JDM 207 valvetrain since theyre built for 8k redlines from the factory. G/L!!!
No oil squirters, but that's more of a detonation control thing I think, as a way to cool the pistons. Bearings are something I hadn't really looked into yet, but I'm operating on the assumption good bearings are out there and easy to get. Not something I'm going to have to invent or hunt for.

Quote:
Originally Posted by Patrick Olsen View Post
There's quite a bit of discussion of high RPM oiling in the Built Motors Discussion forum. I won't claim to be even remotely close to an expert on any of it, but I've browsed through some of the threads. Take a look for the thread about cross-drilled crankshafts, and there are a couple/few big threads about oil pumps (9mm vs. 10mm vs. 12mm, shims and pressure relief settings, etc).

Pat Olsen
I've read those, though the cross-drilling thread went over my head, and there seemed to be no general consensus on if it works, if it's needed, etc. I'll look through again though.
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Old 03-22-2009, 04:08 PM   #11
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Originally Posted by PA-Outback2000 View Post
why do u want to run to 8000rpm on an N/A car?
For the same reason anybody would on a turbo motor. Moving your powerband higher up the rev range means more horsepower, if you can properly gear for it. The RS has Honda-like gears, so its a natural match.
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Old 03-22-2009, 04:13 PM   #12
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Quote:
Originally Posted by Storm View Post
Pat and jimmythagreek pretty much covered the important threads to look at as far as addressing the oiling issues at higher rpms, though I would also suggest looking into the newer dry-sump developments that are currently underway. I think your TWE valvetrain will be good, Delta can make the cams you'd need for that powerband, and I would think that with one of the larger oil pumps running, your motor would be okay sustaining that type of rev range. The return path for oil (in the heads) is pretty large already, but keeping oil around the pickup tube would have to be a high priority, through baffling, accusump or dry-sump.

I've read into the benefits of altering the chamfer on the oiling holes of the crank and agree that it is a good thing to look into doing right from the start.

All of the EJ20_ are DOHC, so you won't be able to directly transfer valvetrain stuff to your SOHC setup. TWE can provide the right springs and retainers for your goal, and the remainder of your intake plans appear to be solid. Don't write off ITBs just yet.....as the TGV housings can be reconfigured to function as ITBs with some work. There's been a bit of a resurgence in interest to that end lately....from both an NA and FI standpoint.

I don't know enough about opensource tuning to suggest that it would be the best way to go. Standalone EM systems have been proven to run well up into that rpm range and beyond.

Get the bottom end oiling planned out and the rest shouldn't be that difficult to build up. I would still be very careful of high sustained lateral g loading at rpms up over 7500 or so. That seems to be where many failures start to happen.

Jay Storm
Dry sump... spendy. I can't afford to spend a ton of money on this, hence building to a single goal, the rev limit. I'm trying to keep it as cheap and simple as I can, and still be able to use this motor for 3 or 4 seasons at least. Will definitely try to baffle and trap the oil pan though, that's a good call.

As for ITBs, it's not that I don't want them... it's just that a stock manifold works and it's no expense, though it may be the biggest power restrictor if I do get everything else together. Down the road if there's a reasonably inexpensive solution I would certainly be interested.
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Old 03-22-2009, 05:12 PM   #13
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BAN SUVS... horsepower is important, but not as important as torque. how much of it you have and where it falls in the power band is the really important matter. this is a link to a high compression engine out of a 1999 N/A RS that i know of...http://xcceleration.com/imp-gallery-rs.htm it doesn't rev to 7000rpm and is done properly. anything short of that won't work. there is a parts list at the bottom of the page. it was drivable on the street for 4 years before they started work on the supercharged version.

the same heads and cams used on this car are used in the supercharged version of it. this is the link..http://xcceleration.com/imp-gallery-rs.sc.htm. there are no hotter head or cam setup for a SOHC that i know of.

a car built by TWE was tried before and didn't last. it was good for maybe 2 seasons of racing. if the head job is just to open up the air volume and use TWE cams, u will loose low-end torque. that car was put together for irish mike in florida.

from what i hear, power will be 250HP at the highest. the power band will start at around 4000rpm and be done by 65000rpm. TWE doesn't make "high rpm" cams. they make stage 1 and 2 cams. they are made for street use. stage 3 isn't made any more. they are mainly made for people who keep within the stock rev range.
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Old 03-22-2009, 05:39 PM   #14
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FWIW.... Irish Mikes abandoned TWE for the NA motor program after spending way too much on bombs. The builder they went to had much better success. Although they did eventually ditch the NA route for FI, until they got screwed by rules, budget and tightwads within SOA.

The plan in this thread is to build a motor that makes more peak HP, higher in the rpm range. That is what the OP has explained (rather clearly) from the beginning. Trying to talk him out of it is not constructive.

Open thy mind to the possibility that maybe...just maybe this plan works out similar to other builds of the same type. There is no harm in building what you want, if that's what you want.

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Old 03-22-2009, 05:44 PM   #15
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Quote:
Originally Posted by PA-Outback2000 View Post
BAN SUVS... horsepower is important, but not as important as torque.
Oh Lord, here we go again.

Quote:
Originally Posted by PA-Outback2000 View Post
how much of it you have and where it falls in the power band is the really important matter.
But wait, I thought horsepower wasn't important? Now I'm all confused.
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Old 03-22-2009, 06:24 PM   #16
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"it" means torque, sorry.

not trying to talk him out of it. i am just saying that it won't work with what he's using.
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Old 03-22-2009, 07:22 PM   #17
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Dry sump... spendy. I can't afford to spend a ton of money on this, hence building to a single goal, the rev limit. I'm trying to keep it as cheap and simple as I can, and still be able to use this motor for 3 or 4 seasons at least. Will definitely try to baffle and trap the oil pan though, that's a good call.
Accusumps aren't too expensive. Certainly a fair bit less expensive than a dry sump system.
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Old 03-22-2009, 08:13 PM   #18
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Originally Posted by PA-Outback2000 View Post
BAN SUVS... horsepower is important, but not as important as torque. how much of it you have and where it falls in the power band is the really important matter. this is a link to a high compression engine out of a 1999 N/A RS that i know of...http://xcceleration.com/imp-gallery-rs.htm it doesn't rev to 7000rpm and is done properly. anything short of that won't work. there is a parts list at the bottom of the page. it was drivable on the street for 4 years before they started work on the supercharged version.

the same heads and cams used on this car are used in the supercharged version of it. this is the link..http://xcceleration.com/imp-gallery-rs.sc.htm. there are no hotter head or cam setup for a SOHC that i know of.

a car built by TWE was tried before and didn't last. it was good for maybe 2 seasons of racing. if the head job is just to open up the air volume and use TWE cams, u will loose low-end torque. that car was put together for irish mike in florida.

from what i hear, power will be 250HP at the highest. the power band will start at around 4000rpm and be done by 65000rpm. TWE doesn't make "high rpm" cams. they make stage 1 and 2 cams. they are made for street use. stage 3 isn't made any more. they are mainly made for people who keep within the stock rev range.
Sorry, but I have no intention of touching anything that comes out of that "shop." They still use Unichips for Pete's sake. Same shop that was selling a turboback, uppipe and Unichip package for the STi and claiming like 450 hp. Pass. On top of that, you failed to notice I won't be using TWE cams and that I specifically said I have no horsepower goal, just an estimate.

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Old 03-22-2009, 08:14 PM   #19
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"it" means torque, sorry.

not trying to talk him out of it. i am just saying that it won't work with what he's using.
Bluntly, you are quacking like a shop lacky/fanboi. Showing up bashing one tuner and promoting another.
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Old 03-22-2009, 08:15 PM   #20
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Accusumps aren't too expensive. Certainly a fair bit less expensive than a dry sump system.
Worth looking into. But, I don't think oiling is the real issue. FHI pulled it off with the Spec C motor, and as far as I can tell they did nothing special with the oiling except a slightly larger pump and maybe some crank work. Not saying the Accusump isn't a good thing, just that I don't think I need to spend even that much more at this time.
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Old 03-22-2009, 09:28 PM   #21
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Originally Posted by Patrick Olsen View Post
There's quite a bit of discussion of high RPM oiling in the Built Motors Discussion forum. I won't claim to be even remotely close to an expert on any of it, but I've browsed through some of the threads. Take a look for the thread about cross-drilled crankshafts, and there are a couple/few big threads about oil pumps (9mm vs. 10mm vs. 12mm, shims and pressure relief settings, etc).

Pat Olsen
A bit off-topic here Pat, but I remember a while back where you were pondering the wisdom of using a rear oil gallery for measuring oil pressure. Did you ever get a satisfactory conclusion to that?

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Old 03-22-2009, 09:40 PM   #22
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BAN SUVS... they use accessports on the turbo cars and perfect power SMT's where they used to use UNICHIPS. they did use UNICHIP back when they did the car in 2001.

the package for the STI u r talking about included is stage 3, which includes an accessport, SRI, large TMIC, BOV, custom 4-1 header up-pipe combo, and TBE. they just finished an 2007 STI Swiss rally car with 650HP and 500 ft.lbs. of torque on 98 octane european pump gas. these guys love this car. here is the link...http://xcceleration.com/imp-gallery-...wiss.gt35r.htm

delta cams are similar to TWE cams. they still won't get you the high-end power you want. which cams will u use then?

who is the "tuner" here that i supposedly dissed on?

i am not a shop lacky. is anyone that says positive things about one place a lacky? if so, everyone is a lacky. everybody likes somebody... who cares? if u like what a shop does, then that's good. in terms of this situation, i personally have had work done to my car and they do great work. that makes me a satisfied customer. don't knock what u probably can't afford or have experienced.
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Old 03-22-2009, 09:50 PM   #23
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delta cams are similar to TWE cams. they still won't get you the high-end power you want. which cams will u use then?
Dude... Delta does custom cams to order on top of several off-the-shelf grinds, one or two of which will work well for me.

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who is the "tuner" here that i supposedly dissed on?
Detla, TWE, and I'm sure if I mentioned anyone else like Cobb you'd try to tell me they suck too. See?
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Originally Posted by PA-Outback2000 View Post
a car built by TWE was tried before and didn't last. it was good for maybe 2 seasons of racing. if the head job is just to open up the air volume and use TWE cams, u will loose low-end torque.
Quote:
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delta cams are similar to TWE cams. they still won't get you the high-end power you want.
Please note that I clearly never said I was using a "TWE motor." I am planning to use TWE valvesprings and retainers. Then your comments that Delta's cams "won't get [me] high end power" is idiotic.

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i am not a shop lacky. is anyone that says positive things about one place a lacky? if so, everyone is a lacky. everybody likes somebody... who cares? if u like what a shop does, then that's good. in terms of this situation, i personally have had work done to my car and they do great work. that makes me a satisfied customer.
Your posts have given me nothing constructive. You clearly haven't read my original post in-depth enough to understand it, you have done nothing to address the questions I've posed here, and you have brought nothing to the discussion except links to that shop and amazement that I won't jump into their arms.

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Originally Posted by PA-Outback2000 View Post
don't knock what u probably can't afford or have experienced.
Ah, there it is. I'm too poor for Xcceleration.com. Now that we've established that, please leave the thread if you have nothing further to contribute than a suggestion that I contact them.

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Old 03-22-2009, 10:18 PM   #24
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A few raw things to look at are intake, exhaust, and cams. Intake and exhaust primary piping diameter and length will play a sizable roll in shaping the power curve. The cams will define where this power curve mainly lies. Match the parts appropriately.

Just a quick point to cams and the effect on the power band from another user's dyno graphs:
http://forums.nasioc.com/forums/show....php?t=1682242

Comments/data on the Delta cams:
http://forums.nasioc.com/forums/show....php?t=1416850

I am curious what you can get out of the SOHC versus the DOHC when you do tune both for high rev use. Historically, one thinks DOHC as high rpm geared and SOHC as low rpm geared. However, once you toss cams into the engine, even the SOHC provides an extended HP band. It might depend more on how focused you'll be. The SOHC may provides broader usability, i.e. not losing low/mid just to eek out a little on the top.

Intake manifold info:
http://www.team-integra.net/sections...?ArticleID=466

An accumulation of exhaust info I've run across in the past:
http://forums.nasioc.com/forums/show....php?t=1080151

Cobb's old tech articles on the NA engine(not sure why Cobb no longer has these on their site). They have some numbers and did some bench flow testing of the intake and heads. They have some comments on making the NA engine flow better.
http://web.archive.org/web/200502030...ech/index.html

It seems if you get these few parts set up right, you're80%-90% where you want to be. Then it's more little things to improve flow/efficiency and you start porting and polishing everything.
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Old 03-22-2009, 10:32 PM   #25
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Originally Posted by Back Road Runner View Post
I am curious what you can get out of the SOHC versus the DOHC when you do tune both for high rev use. Historically, one thinks DOHC as high rpm geared and SOHC as low rpm geared. However, once you toss cams into the engine, even the SOHC provides an extended HP band. It might depend more on how focused you'll be. The SOHC may provides broader usability, i.e. not losing low/mid just to eek out a little on the top.
My guess is that the number of cams has little to do with anything. The one downside to the design that I see is that you can't find some adjustable cam gears to screw around with your open/closing times- you have to get it right the first time. But runner size/shape and cam lobe shape are pretty much all there is to how well a head works, right?

Quote:
Originally Posted by Back Road Runner View Post
It seems if you get these few parts set up right, you're80%-90% where you want to be. Then it's more little things to improve flow/efficiency and you start porting and polishing everything.
So it seems. The build target is just relative durability at these RPMs; figuring out the cams and headwork is pretty simple, no rocket science or new technology there.

Thanks for the links, I'll go through them all and re-post anything that really stands out for me.
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