Originally posted by geoff
one difference is that the y8 is single cam and the zc motor is dohc.
Not all zc is dohc
Originally posted by chet
to say the a6 head is better for boost over 20psi doesn't really make any sense either. stock vs stock the better head will be one that can flow more air. in this case, its the vtec head as honda designed it to make more horsepower on the high lobe and the rest of the head is designed accordingly.
Considering were not talking about stock for stock, the a6 head were speaking of is capable of moving more air than a stock y8 head.
As far as linearity, when you spool 15psi before 5k rpm, you don't have much tuneability for vtec crossover on a single cam head.