Not trying to sound like a punk by the title, but every time that I ask this question, I just get a flood of "NOPE, NOT ON A POSITIVE DISPLACEMENT BLOWER CAR, NO WAY!! First off, I know you will most likely lose boost and retain the same power, but if you have a twinscrew or turbo, you can safely gain that boost back again. I want to do many things to my car and I'm not convinced that head porting would be a waste in my case. I want to do a twinscrew and LTs, I already have crower stage 3 blower cams, and when this shortblock gives up, I'll go with a VT 302, 304, or 324. Anyone that has any dynos or write ups on ACTUAL 03-04s with this done to them, please post up. If you don't have proof supporting that it is not worth doing, please don't tell me what I've already heard 1000Xs. The reason that I'm asking this is that Stiegemeier just recently started 03-04 Cobra head porting and he's got me curious. Here's his breakdown on stage 1, 2, and 3 head porting for our cars:
All stages have bronze guide liners.
Stage I:
Custom Stiegemeier valve work 46 degree radius.
All maching done on a Serdi 100
CBN surfacing bowl blend and deburing
Precision assembly with new seals
about 25hp
Stage II:
All above plus
Max Exhaust Porting
Intake Blue Printing
about 40hp
Stage III:
All above plus
Max Intake Porting and Chamber Polishing
about 50hp
Now granted, you may not be able to bolt them straight on and see gains, but if you repulley the blower or turn up the boost on the turbo to make up for what boost you loose...what then?
All stages have bronze guide liners.
Stage I:
Custom Stiegemeier valve work 46 degree radius.
All maching done on a Serdi 100
CBN surfacing bowl blend and deburing
Precision assembly with new seals
about 25hp
Stage II:
All above plus
Max Exhaust Porting
Intake Blue Printing
about 40hp
Stage III:
All above plus
Max Intake Porting and Chamber Polishing
about 50hp
Now granted, you may not be able to bolt them straight on and see gains, but if you repulley the blower or turn up the boost on the turbo to make up for what boost you loose...what then?
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