I have an '83 and the block had flat top pistons. Well, I blew it up and swapped it out for an '80 block that apparently has dished pistons. Should I just leave the n47 head on there or would it be an advantage to put my old p79 head on there?

Thanks.


BTW, sorry for bringing back such an old thread.

Leave the P79 on there. It has a better quench and will give you proper compression for a turbo.

Well for one thing I dont have a turbo and another thing is I thought I read somewhere that the p79 didnt work with dished pistons. Just wondering.

"BleachZee Leave the P79 on there. It has a better quench and will give you proper compression for a turbo. "


WTF P79 and turbo are, you guys need help. P79 have exhaust liners cast into the head to lower emissons and not increase flow. the N42 which has the smaller chambers longer valves is a good option, the P90 is a geat option and the P90a which no one even mentioned is another option. No body in there right mind would port a P79 you gain nothing. Not to be a Dick but do a search on hybridz.org where the real z rome.




tbs
13.0 1/4 81zxt 84eccs

Sorry about the turbo assumption. I think I was thinking this is the guy who put a turbo on his non-turbo engine... but I was wrong. Wrong thread.
Anyway, he just asked if he should use an N42 or P79. He didn't ask what head overall he should get. Knowning that he just wants to fix his N/A engine, he should go with the N42 that came with the replacement block.

Nobody mentinoned porting a P79, but if you remove the steel exhaust liners you can port the P79. More important is the intake ports though, not the exhaust.

The problem is that this thread was brought up from the dead and the subject matter changed. Please start a new thread for your question to help eliminate confusion.