Friday, January 12, 2007



05 Subaru WRX (EJ25) with DBW throttle conversion, FMIC, HKS 3037 turbo, HKS EVC 5 BC, fueling mods, AEM. Stock head and cams. Short block rebuilt using stock pistons, rods, bearings etc. Chart provided by customer; recorded 350 whp @ 1.33 bar. Fixed the dip in torque at the upper range.

Some quick calculations to validate the observed data:

44 lb/min of air is needed to produce 415 bhp.

Assuming intake air temperature is 40 degC, VE of 97%.

Therefore required MAP pressure is 44 * 639.6 * (460+104) / 0.97 * 3200 * 151.25 = 33.8 psi absolute, or gauge pressure of 33.8 - 14.5 = 19.3 psi. Or 1.33 bar of boost pressure.

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