Is a 235cc intake runner too big for a S1 head? Would a head with a smaller runner (say mid 220s) yet similar flow numbers make more power on a small (<230) cammed car, and if so, how much?

Shawn

 

not at all... almost all fully ported ls1 heads are that large of an intake runner. Ive seen no real difference other than maybe an afr 205 could make a little more bottom end torque.

I wouldnt run a less ported 220cc ls1 head..i dont think itll make more low/midrange.

 

LOL that depends on what each head flows. personally I dont think 235cc is too big. It is fairly big but nothing drastic for a head with that cam size.

 

I'm asking because the potential buyer of my heads has been calling some local head porters, and they have him convinced that the runner volume is too much, and that they have possibly been "overported" for lack of a better term. My car dynoed 410/382 with S1 heads, small (<230) cam, through full exhaust (no cutout), full belts, through a 4.30 geared 12 bolt and (heavy ***) 18x10.5" wheel and 295/35/18 tire combo, which I thought was a fair number.

Thanks, Shawn