90LX, in case there's any confusion, I don't think the motor is going to put out bad numbers at all. Many people speak as if big heads will cripple an small motor, and I completely disagree with that sentiment. To the contrary, though I am inclined to believe that there is a benefit to port velocity, I'm really just discussing the merit of the idea with Nik to help me flesh out or negate relevant points in the argument for and against port velocity. This conversation is actually quite insightful to me. I could just as easily argue the other side and play devil's advocate, and would if someone strongly believed that smaller heads are the only way to go. That said, please feel free to join in. I value your opinion and thus welcome your input. Now, on to your comments. Please fill me in on the details on the LS3 heads. I really don't know anything about them. About them being at home on an LQ4/LQ9, I suppose I'll have to take your word for it. Have you any basis for comparison between this head and a conventionally wise smaller head? I really want to see a comparison done. About your combo, people are idiots! You had big heads, but you also had a Dart stroker with the potential to rev to the moon. Your motor is in the same boat as mine, though mine is boosted and at lower RPM - a topic I'd also like to know more about. Some claim that boosted motors work better with bigger heads than normal - a belief that I am more strongly inclined to disagree with. That however is another topic worthy of a separate thread, if you'd like to delve into that topic. The carb thing is a good point, though in this case the carbs on each motor were identically sized. I'd assume that any advantages from EFI would be present on both motors. Yes, again I agree with your point, but the requisite counter point is that these offerings were the best Ford and Chevy could do at the time in the Trans-am program that these companies were spending huge amounts of money trying to one-up each other on. I don't have any quantitative analysis, but my intuition tells me that both heads must have had nearly equivalent efficiency. Today's efficiency would likely affect each in the same way. The 162cc heads on the Chevy likely pale in comparison to an AFR165 today. I think a close comparison would be a similar sized CHI head vs. an AFR165 on the chevy. It would be a fun comparison for the purpose of our argument. I just haven't seen, but am dying to see an engine masters challenge that measures only the average power across a 3500-6000 RPM powerband. That, I believe, would definitively answer the question. I know they did something like that this past year, but I don't recall the details, and don't remember the powerband they competed over. Kasse was not the only guy working with the CHI heads, but his team is the winningest one. Hopefully you've got the magazine and can tell me What's ironic to me about the motors is that it looks like the chevy had a high revving cam in their 302 while Ford had a lower revving one. Both motors probably liked to be shifted at around 7k RPM, though. The counterpoint here is that if the Chevy was more mildly cammed, I think we'd see significantly higher numbers down low. No idea... could you please explain it to me all over again?