I am thinking of going with a different head on my zz4. what is everyone else running" i do not want to switch my cam, just the heads. what will get me to 400 h.p. in the head dept. i also want to run 87 octane instead of prem. let me know your combo.

1.6 rockers and vortecs?

 

I'll be using AFR 180's (if they ever get here) with the zz4/tpi. I think that would be your best bet, but 400hp? Meh....

 

who makes afr 180's? what compression?

 

www.airflowresearch.com makes them, you can get them in 68 and I believe 74cc chambers. With flat tops/4-valvereliefs and piston to head clearance of about .045 you should be somewhere between 9.75 and 10:1 (with 68cc chambers). www.tenperf.com seems to have the best prices....... but be warned, they are on a two month wait .

 

isnt the zz4 10.0 1 compression w/ a 64cc head. im almost positive it is. so going to a 68 you will lose a few comp points probly be @ 9.7 ?.and i dont think just putting afr heads will get you 400 hp. youll need aftermarket runners, plenum( port it ) and a 52 mm tb to get close to 400. also the zz4 cam is kinda weak, there are far better cams out there. especially if you are taking the heads off anyways your more then 9/10's there. but its just my .02$
i know my dads zz4 ran like hammered sh*t. its advetized 355hp and 405 torque had to be an overestimate. we took it apart and had the heads shaved and ported the intake , after that i believe it had the posted numbers.

 

go with the afr heads. they kick ***. just hope you dont wait as longf as i had to..about three and a half mounths for them. you should look into bigger runners....also why not look into holleys stealth ram.

 

Whats the piton to head clearance on a zz4 crate engine?