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Old 09-17-2020, 11:03 PM   #51
subaru_gc8
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personally I dont really get the destroked 2.5. I guess I can see if you are going to rev to 9000 or more but why loose the low end if you dont have to? especially if its a dd.
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Old 09-18-2020, 06:54 PM   #52
FuJi K
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personally I dont really get the destroked 2.5. I guess I can see if you are going to rev to 9000 or more but why loose the low end if you dont have to? especially if its a dd.
I'd say it works fine to up to a 62mm turbo MAX. After that the larger 2.5L engine will give you more power with the same powerband. People still think it's some black magic to rev a 2.5L past 7000rpms. For me personally, 8000rpms on a 600-700whp 2.5L setup is normal.

Fuji
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Old 09-18-2020, 07:54 PM   #53
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I'd say it works fine to up to a 62mm turbo MAX. After that the larger 2.5L engine will give you more power with the same powerband. People still think it's some black magic to rev a 2.5L past 7000rpms. For me personally, 8000rpms on a 600-700whp 2.5L setup is normal.

Fuji
yea i totally get waht your saying, but i guess at that point of running to 8000 you will loose resolution in your tune so you have to go aftermarket ecu I guess my thinking is if you are going to go that route, you should go all the way or youre not really making use out of the set up... you know trying to get everything to match
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Old 09-19-2020, 11:12 PM   #54
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What turbo? 450whp or crank? What model year, transmission choice?
GTX3576, whp but horsepower gains are not my focus, just looking to build a solid club racer/ auto cross that is capable of high horsepower but will be tuned to my driving skill (novice) and for the local track. 2009 Sti hatch, stock transmission for now, drivetrain hopefully upgraded with time.

Current engine mods:

Radium rails
ID 1050 cc
Perrin EL headers
Cobb Turboback
Cobb AP V3
AEM fuel pump
KillerBee baffle and pick up
aos

Next stage:

FMIC
Rebuilt shortblock
Big turbo + ext WG
Dry sump
Standalone

Goals: Solid track car that exceeds my skills and can still be city driven with little to no future limitations.

Any input is appreciated.

Last edited by PlayersLtd; 09-20-2020 at 01:25 AM.
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Old 09-21-2020, 01:22 PM   #55
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For a GTX3576R, a destroker vs 79mm stroke 2.5 is personal preference to if you want an engine that likes to rev vs more low end grunt.

In reality, the turbo will be out of steam long before you use any revs that a 2.5 couldn't.

With that being said, when Dom and I first went about doing the destroked engines, we had the mindset of it simply being a bigger EJ207. The high revs that it could take would be nice for track use in which you could over-rev heading into a corner to avoid a short upshift and subsequent downshift.

So there are pros to it beyond simply comparing power and torque figures.
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Old 09-21-2020, 10:31 PM   #56
subaru_gc8
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Originally Posted by Homemade WRX View Post
For a GTX3576R, a destroker vs 79mm stroke 2.5 is personal preference to if you want an engine that likes to rev vs more low end grunt.

In reality, the turbo will be out of steam long before you use any revs that a 2.5 couldn't.

With that being said, when Dom and I first went about doing the destroked engines, we had the mindset of it simply being a bigger EJ207. The high revs that it could take would be nice for track use in which you could over-rev heading into a corner to avoid a short upshift and subsequent downshift.

So there are pros to it beyond simply comparing power and torque figures.
what if you use a 1.2 ar housing?
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Old 09-22-2020, 06:19 PM   #57
FuJi K
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MY99 GF4 JDM 6spd
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Quote:
Originally Posted by PlayersLtd View Post
GTX3576, whp but horsepower gains are not my focus, just looking to build a solid club racer/ auto cross that is capable of high horsepower but will be tuned to my driving skill (novice) and for the local track. 2009 Sti hatch, stock transmission for now, drivetrain hopefully upgraded with time.

Current engine mods:

Radium rails
ID 1050 cc
Perrin EL headers
Cobb Turboback
Cobb AP V3
AEM fuel pump
KillerBee baffle and pick up
aos

Next stage:

FMIC
Rebuilt shortblock
Big turbo + ext WG
Dry sump
Standalone

Goals: Solid track car that exceeds my skills and can still be city driven with little to no future limitations.

Any input is appreciated.
A GT3076 size turbo on E85 or race fuel will easily make this power with a quicker spoolup and nice mid range torque on the standard 2.5L. Are you targeting to move the powerband up the rev-range? That's what the destroke 2.5L does.
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