sneaky98gt
10 Year Member
I concur, most of the shops I deal with are seeing about ~10RWHP gains with the TFS heads over well done PI heads on a combo like this. Logan Motorsports was the first to test 3 sets of TFS and find 8RWHP the biggest difference against his custom Livernois PI heads (and got roasted online for saying it). Change the graph in the opening picture to SAE and its ~330RWHP which is pretty close to a 233 duration cammed, TFS intaked, ported PI head motor in output. Some numbers I am seeing thrown around here make it sound like the TFS is making more power than a 4V head which I can assure you it is not.
+ ∞.
375 rwhp from nothing but heads and cams? Pa-leeze. That's more than a stock Terminator makes. And it's got 4 valve heads and a blower. Maybe a car did make 375 (or 350, or whatever) on a particular day on a particular dyno with a particular correction factor, but I bet it won't run much (if any) faster at the track than a ported PI/cammed/full bolt on 2 valve (making 325) does.