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Old 06-16-2008, 06:04 PM   #276
mspeed555
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Old 06-17-2008, 12:35 AM   #277
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great thread dude, someone should sticky this def
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Old 07-08-2008, 01:27 AM   #278
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thanks everyone for all the good info!
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Old 07-08-2008, 05:18 AM   #279
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tons of great info. helped alot.
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Old 07-08-2008, 05:27 PM   #280
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A few questions after reading 12 pages of good info.

Let's say I'm starting with a car that has:

- borla UEL
- some kind of catback
- cams

Roughly how much power would I gain with each add-on in the following order:

- CAI
- HFC
- IM PnP
- Head works (not sure exactly what)

Thanks.
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Old 07-12-2008, 12:45 PM   #281
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I briefly re-read this sticky. I didn't come across anything that delt with differnt head combonations on the ej22 block. could some one post their results, and or engineering #'s.
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Old 07-12-2008, 01:30 PM   #282
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Quote:
Originally Posted by lh0628 View Post
Let's say I'm starting with a car that has:

- borla UEL
- some kind of catback
- cams

Roughly how much power would I gain with each add-on in the following order:

- CAI
5-10hp. I'm sure some will disagree, but that's what I saw. With that said, I think you really need some sort of fuel controller to take advantage of the change. I don't believe an ECU reflash is available for your model year, but I'm not sure. If it is, I'd look into that.

Quote:
Originally Posted by lh0628 View Post
- HFC
Not much - maybe a couple HP?

Quote:
Originally Posted by lh0628 View Post
- IM PnP
Minimal gains, although that's somewhat of a guess. Nobody has really played much with the IMs from what I've seen. If you search for SOLUTION's posts, you'll see he tried to put an '05+ IM on his pre-'05 SOHC car. I vaguelly recall that in the end he gave up, but I could be wrong.

Extrude-honing the manifold costs big bucks - I think in the $500 range, but it's been a while since I checked E-H's website. Since nobody really knows what the pay-off would be in actual performance gains, that $500 is a tough pill to swallow.

Somewhere around here is some flow data from Cobb from a few years back. They found that the IM runner flowed more than a stock intake port, so they essentially said the IM is not a restriction. For those of us with head work and cams, though, that's quite possibly not the story. Jay Storm (aka "Storm") has a pretty cool custom IM on his DSP car and apparently it was well worth it.

Quote:
Originally Posted by lh0628 View Post
- Head works (not sure exactly what)
There's certainly power to be had from head work, but it ain't cheap, and it's not something I would trust to just anyone. Porting and polishing heads is as much art as science, so it's not something I would trust to a local race shop that is used to porting SBF or SBC heads.

Pat Olsen
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Old 07-12-2008, 01:42 PM   #283
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Has anyone tried using jdm turbo heads on a NA block?
I saw on another post that the single port heads got more HP then the dual port heads. From advice form builders i've been advised to use the dual port heads.
With out any "work" or parts added what heads would be a perfect fit on an ej22?
With part availability aside, what head would be the best to use if you were up grading and working on the heads(not including valve control)?

What exactly is wrong with the subaru NA exhust heads? The are EL headers.
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Old 07-14-2008, 12:31 PM   #284
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Thanks Pat. So it looks like the only clear option for power is cams.

Quote:
Originally Posted by Patrick Olsen View Post
5-10hp. I'm sure some will disagree, but that's what I saw. With that said, I think you really need some sort of fuel controller to take advantage of the change. I don't believe an ECU reflash is available for your model year, but I'm not sure. If it is, I'd look into that.
I know i-speed can flash MY02 ECUs, and Yoshio from Toronto can as well. I don't know what fuel controller will work on MY02 and how much they cost. Can you recommend one?

Quote:
Originally Posted by Patrick Olsen View Post
Not much - maybe a couple HP?
Good, I want to keep my stock cat.

Quote:
Originally Posted by Patrick Olsen View Post
Minimal gains, although that's somewhat of a guess. Nobody has really played much with the IMs from what I've seen. If you search for SOLUTION's posts, you'll see he tried to put an '05+ IM on his pre-'05 SOHC car. I vaguelly recall that in the end he gave up, but I could be wrong.
I think he abandoned the project and sold the IM.

Quote:
Originally Posted by Patrick Olsen View Post
Extrude-honing the manifold costs big bucks - I think in the $500 range, but it's been a while since I checked E-H's website. Since nobody really knows what the pay-off would be in actual performance gains, that $500 is a tough pill to swallow.

Somewhere around here is some flow data from Cobb from a few years back. They found that the IM runner flowed more than a stock intake port, so they essentially said the IM is not a restriction. For those of us with head work and cams, though, that's quite possibly not the story. Jay Storm (aka "Storm") has a pretty cool custom IM on his DSP car and apparently it was well worth it.
Then how about just a simple polish? Is that worth doing at all?

Quote:
Originally Posted by Patrick Olsen View Post
There's certainly power to be had from head work, but it ain't cheap, and it's not something I would trust to just anyone. Porting and polishing heads is as much art as science, so it's not something I would trust to a local race shop that is used to porting SBF or SBC heads. Pat Olsen
I know Delta cams is starting to offer head works now. But if I PnP heads, should I do IM and TB as well?
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Old 07-14-2008, 04:33 PM   #285
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Quote:
Originally Posted by ROC pit-bull View Post
I briefly re-read this sticky. I didn't come across anything that delt with differnt head combonations on the ej22 block. could some one post their results, and or engineering #'s.
You don't generally see it discussed in this forum because going that route is usually reserved for a Forced Induction application. The combustion chamber of the Ej25 heads are bigger than the ej22 ones, and drop the compression ratio down into the 8's. Same thing with the JDM Ej20 heads. Some of those heads have giant combustion chambers that would take you down in the the 6's when mated to the Ej22E blocks. Guys do it all the time, just not for NA power.
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Old 07-14-2008, 05:21 PM   #286
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Quote:
Originally Posted by Matt Monson View Post
You don't generally see it discussed in this forum because going that route is usually reserved for a Forced Induction application. The combustion chamber of the Ej25 heads are bigger than the ej22 ones, and drop the compression ratio down into the 8's. Same thing with the JDM Ej20 heads. Some of those heads have giant combustion chambers that would take you down in the the 6's when mated to the Ej22E blocks. Guys do it all the time, just not for NA power.
Thanks, You think a crowned piston can compensate for the lower compression?
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Old 07-14-2008, 08:13 PM   #287
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You discussed the ej25 and ej20 heads, but what about just putting the ej255/257 heads on an ej253 block? Those are dual cam aren't they? Would the fact that they are on the wrx and sti engines effect the compression on the ej253 engine in the same way?
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Old 07-14-2008, 09:30 PM   #288
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Quote:
Originally Posted by ROC pit-bull View Post
Thanks, You think a crowned piston can compensate for the lower compression?
Sure it can. The trade off is that you lose the cheapness that most people are looking for when they are doing the lego engines. I personally have wanted to build an 9000 rpm revving NA Ej22 for years. I think it's the perfect balance of torque and ability to rev. But such a thing would not be a cheap build.
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Old 07-14-2008, 09:34 PM   #289
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Quote:
Originally Posted by dzrt_hrd View Post
You discussed the ej25 and ej20 heads, but what about just putting the ej255/257 heads on an ej253 block? Those are dual cam aren't they? Would the fact that they are on the wrx and sti engines effect the compression on the ej253 engine in the same way?
The issue for most of us with possibly using the Ej255/257 heads is that we have earlier engines and ECUs that aren't compatible with the cam sensors and pickups found on the late model heads.

And then you've got to consider that the cam grind of a high performance FI application isn't generally the best for a performance NA application. So you'd be shopping for cams.

The other thing is that I don't honestly know what the combustion chamber volume of those heads is. I couldn't tell you the impact on CR without knowing that bit of info...
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Old 07-16-2008, 09:05 PM   #290
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If you haven't noticed yet I'm fishing for ideas for my own car, trying to do some research on what I need to look for. If the compression on the 255 heads were too low, I could just have them sanded down, yes? And for the cams it makes sense that the stock ones are intended for FI would be different, but in what way? How are FI cams different than NA cams? By the way I did the forum searches on the topic, but cams hadn't come up.
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Old 07-17-2008, 02:55 PM   #291
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This is a great thread!

I just bought an 08 2.5i, is there anything that I can do that won't void the warranty?

Thanks
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Old 07-22-2008, 12:56 PM   #292
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you might want to speak with the subaru service manager from where you got the car. He will tell you if they take the car with aftermarket parts or not.

Also take into account that SPT parts should not void the warranty but I read that some people got their warranty canceled due to the use of these because it is "offroad use only"
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Old 07-22-2008, 02:33 PM   #293
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back to the polished IM. I have done this on a 2001 RS, took out casting flaws, opened up the head side a little, made the TB side glass smooth(as far as I could reach in there), smoothed out the idle air passage, and saw.....not much. It felt a little smoother, but that's about it.

I did it to get to know the IM better and since I had time and felt like it, I did it.

mods at the time were:
CAI
borla UEL headers, 2.25" exhaust, 1 normal cat, stromung muffler
cobb mild cams
lw flywheel/pulley
polished TB
SAFC

a month or 2 later I cleaned up the welding flaws on the headers where it mates to the heads, that made more of a difference and made everything quite a bit smoother.
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Old 07-22-2008, 05:03 PM   #294
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about the exhaust not being bigger than 2.25 inches, is there a dyno test that proved that anything bigger actually lost power? thanks
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Old 07-22-2008, 06:40 PM   #295
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Quote:
Originally Posted by tcoffin014 View Post
about the exhaust not being bigger than 2.25 inches, is there a dyno test that proved that anything bigger actually lost power? thanks
I recently did a full rebuild on my EJ22 with an overbore and lots of headwork and intake work. I used the stock headers with a custom 2.25" exhaust, including just a Random Tech hi-flow cat and a FloMaster Series 40 muffler. It was way too loud, so I added a Vibrant Tech resonator, and then another. Adding the first resonator also made a very noticeable improvement in throttle response and power under 4k RPMs (as I wasn't going any higher on the new engine then). Adding the second resonator smoothed it out a little more, but it didn't make any noticeable increase in power.

While that may be just butt dyno measurements, I would expect any more that 2.25" would just be worse.
-N
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Old 07-22-2008, 11:45 PM   #296
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This most def. needs to be stickied.
Regarding this statement.

"Typically a good resonator in the midpipe will restore the "rumble"."

Elaborate please. I need more rumble in my life.
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Old 08-19-2008, 12:28 AM   #297
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good read, why isn't this stickied?
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Old 08-19-2008, 12:38 PM   #298
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Quote:
Originally Posted by bulletproof4130 View Post
This most def. needs to be stickied.
Regarding this statement.

"Typically a good resonator in the midpipe will restore the “rumble”."

Elaborate please. I need more rumble in my life.
http://www.youtube.com/watch?v=VFvjsn8tvcw&feature=user
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Old 08-19-2008, 04:35 PM   #299
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That car already has UEL headers. I was talking about for the EL cars.

Sounds good though.
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Old 08-19-2008, 06:34 PM   #300
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nope that car has the stock headers.
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