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Cheater240SX · 01-31-2002, 07:38 PM

EGR is in no way a power hit.  It only comes on at part throttle cruising.  How can you be sure?  Intake manifold vacuum is what draws it in.

Gas tank vapor purge has no power hit.

PCV--no power hit.

The real power hit is the cats.  They usually impose a 5-8% power reduction.  So that could mean a gain of about 10 hp.

Removing the butterflies in the intake is a good idea to get power.  These are called either CMCV (Charge Motion Control Valves) or IMRC (Intake Manifold Runner Control)  Sounds like CMCV on the KA.  These close at low load to promote better air/fuel mixing.  They open at high load (rpm, throttle angle), but they still inhibit air flow through the runners.  Mustang Cobra guys pull theirs out too and claim a slight power increase.  

01-31-2002, 07:38 PM	#11
Cheater240SX Join Date: Jan 2002 Posts: 40 Trader Rating: (0)	EGR is in no way a power hit.  It only comes on at part throttle cruising.  How can you be sure?  Intake manifold vacuum is what draws it in. Gas tank vapor purge has no power hit. PCV--no power hit. The real power hit is the cats.  They usually impose a 5-8% power reduction.  So that could mean a gain of about 10 hp. Removing the butterflies in the intake is a good idea to get power.  These are called either CMCV (Charge Motion Control Valves) or IMRC (Intake Manifold Runner Control)  Sounds like CMCV on the KA.  These close at low load to promote better air/fuel mixing.  They open at high load (rpm, throttle angle), but they still inhibit air flow through the runners.  Mustang Cobra guys pull theirs out too and claim a slight power increase.