WRX 2.0 turbo vs USA 2.2 turbo
Posted: Wed Sep 19, 2001 3:13 am
Ok we haven't kicked this around for a while. I have to jump in here with my 20 cents. The WRX 2.0 turbo engine may not be superior to our USA 2.2 turbo engine. The USA 2.2 is more closely related to it's little WRX 2.0 sister than to all of the weak cousin normally aspirated engines. They are both engineered from the ground up as turbo engines with internal goodies to strengthen and lubricate critical components. There are some differences.
One favorite difference is the double overhead cam 2.0 vs the single overhead cam of the 2.2. It is generally acknowledged the 2.0 DOHC can be made to rev higher. This is important if you plan to race. However, the 2.2 is ten percent bigger. This is important if you plan to race. The stroke is the same at 75 mm, but the EJ22 bore is 96.9 mm vs 92 mm in the EJ20. How much higher does that little 2.0 have to rev to offset the 10% size differential?
Head flow studies I have seen show the stock heads from the late 2.5 engines to be superior to the 2.2 heads, and the 2.2 heads superior to those in the 2.0. You can fit the 1995 thru 1999, Phase I, 2.5 heads to get double overhead cams if that's what you think you need or want. It's likely the performance increase from such a retrofit will be the result of the superior flow characteristics than the higher rev potential.
The 2.0 has a compression advantage off boost with 9.0, I think, against 8.0 for the 2.2, so the torque provided by the extra compression may offset the torque delivered by the greater displacement at low RPM, but the lower compression of the 2.2 should permit higher boost, and here is where the performance difference really comes down to it. The WRX uses a larger turbo with higher boost.
The EJ22 turbo engine is very nearly just a larger, detuned for the US market version of the WRX motor. Don't get rid of it for a smaller engine, work with it. The addition of a simple boost controller should deliver mild WRX power levels for a few dollars. If you want more power, coupled with proper fuel management, the BC-BF turbo engine closed deck design will permit a larger turbo and even more bang than the wilder WRX engines, for less buck.
The EJ22 is a direct descendant of the motor used to power the legendary 2.2 liter 22B cult car, generally acknowledged to be the wildest Subaru to ever live.
I would be interested to read opposing views.
Larry EJ22 Witherspoon
To unsubscribe from this group, please send an email to:
BC-BFLegacyWorks-unsubscribe@egroups.com
zZz <http://docs.yahoo.com/info/terms/> .
One favorite difference is the double overhead cam 2.0 vs the single overhead cam of the 2.2. It is generally acknowledged the 2.0 DOHC can be made to rev higher. This is important if you plan to race. However, the 2.2 is ten percent bigger. This is important if you plan to race. The stroke is the same at 75 mm, but the EJ22 bore is 96.9 mm vs 92 mm in the EJ20. How much higher does that little 2.0 have to rev to offset the 10% size differential?
Head flow studies I have seen show the stock heads from the late 2.5 engines to be superior to the 2.2 heads, and the 2.2 heads superior to those in the 2.0. You can fit the 1995 thru 1999, Phase I, 2.5 heads to get double overhead cams if that's what you think you need or want. It's likely the performance increase from such a retrofit will be the result of the superior flow characteristics than the higher rev potential.
The 2.0 has a compression advantage off boost with 9.0, I think, against 8.0 for the 2.2, so the torque provided by the extra compression may offset the torque delivered by the greater displacement at low RPM, but the lower compression of the 2.2 should permit higher boost, and here is where the performance difference really comes down to it. The WRX uses a larger turbo with higher boost.
The EJ22 turbo engine is very nearly just a larger, detuned for the US market version of the WRX motor. Don't get rid of it for a smaller engine, work with it. The addition of a simple boost controller should deliver mild WRX power levels for a few dollars. If you want more power, coupled with proper fuel management, the BC-BF turbo engine closed deck design will permit a larger turbo and even more bang than the wilder WRX engines, for less buck.
The EJ22 is a direct descendant of the motor used to power the legendary 2.2 liter 22B cult car, generally acknowledged to be the wildest Subaru to ever live.
I would be interested to read opposing views.
Larry EJ22 Witherspoon
To unsubscribe from this group, please send an email to:
BC-BFLegacyWorks-unsubscribe@egroups.com
zZz <http://docs.yahoo.com/info/terms/> .