Ok i need your guy's help H-T!! mainly the pro's help. the motor that I'm OH SO SLOWLY building due to lack of a job is still very slowly coming together. w that said the set up is this: a6 block, stock crank bore all the stuff, with pm7 pistons/rods from a DOHC zc, a z6 head(which as far as i know it's still virgin too) for mad vtekz (lol) and i'm wanting to use a y8 head gasket.
i know the pm7's aren't that much of a dome compared to what some people use, but should i be worried about my valves hitting the piston face when vtec cracks or perhaps even when i'm just driving it? anything special i should do to test fitment before i throw it all together?
according to the zeal auto works compression calculator i could essentially make just under 12:1 with a z6 hg and like 12.3:1 w a y8 two layer hg.

sorry about the n00bish ness of this thread but i'm still learning stuff and have no idea about what these numbers mean but want to know and want my stuff to run good. hopefully i can still run this motor on pump gas. should be fast... i'm bolting it up to an si trans.

thanks!!

p.s. should i post this in the all motor section too?

 

Not much of a pro here - and you prob. considered it already - using clay to check valve/piston clearance.

 

damnit no i didn't even think of that. lol basically i know how to take it apart and put it back together w stock parts, but when it comes to engine mods... i'm soooo lost. lol but i'm learning!!

 

Yeah what he said. CLay reassemble head and turn motor slowly and pay attention for any contact if theres any stop immediately, adjust if possible.

 

so i was reading in some one's thread about using a ball bearing to work as the vtec actuator, is this correct?

 

You wont have any valve clearance issues, ive allready built a z6/p29 piston setup, it worked fine but the ring lands on these pistons are weak and prone to cracking. also the huge dome of the pistons arent that great they hinder performance at low rpm's and require you to walk a fine line of very advanced timing.

I personally would never use them again, i would go with pg6's they are a much better piston with very little valve clearance issues, and they have a great flat top, wich doesnt hinder performance but still bumps up compression. The y8 head gasket is the same as the z6. and if your looking to run a thin headgasket with that build your going to end up with 13+ to 1 compression it is not worth it on a stock head its way too much of a pain in the *** to tune unless you get a large lift cam and bleed off some low rpm dynamic compression.