I have a 280zx with p90 head and flat top pistons. Can anyone enlighten me as to how to get the compression tp 10:1 (without spending too much cash) and it should run on normal pump gas shouldnt it?

Thanks Wes

Since I'm not too familiar with the Zx engines I'll give you an idea at what you are trying to accomplish.

I believe the zx motors were around 8-8.5:1 stock. So you would probably be looking at a different set of pistons at the very least. You might need to shave the head a little (then shim the cam towers) to reach 10:1.

Try looking at the Datsun Garage in the links section for more info, I'm just giving you a guess.

10:1 would run OK on pump gas, as long as it's premium. I doubt you could use any grade less. Any more compression than 10:1 and you would likely have to use some sort of additive.