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I am getting into my piazza in the weekend finally

I was toying with the idea of selling the 4z and using something else but in the end i come to the conclusion you guys are getting pretty good numbers out of the 4z's so i'll go down that route.

I'm going to keep with the standard bottom end at the moment and do some head work. Which leads me to my questions.

What do you guys do to the heads to make them flow more??

Are larger valves available to fit the 4z heads??

what type of head gasket do you use?? Is the standard one good enough for more boost?

If you can get the original 4zc1-T head gasket you would be well served, some of the aftermarket ones are crap. The alternate is the mono torque but don't stick to the bullshit about the mono crap. Re torque after about 500km's. You should talk to Madmike, he has done diddly squat to the donkey and glued on a bigger turbo...its a scary thing now believe me.

Make sure the exhaust is free flowing as well at least 2-1/2" all the way, 3" if you can arrange it.

A head without those jets above the inlet valves might give you more room for porting, I assume non turbo 4ZC1's don't have em. Bigger valves could probably be used off a 4ZE1.

I'm using an Isuzu head gasket but i've only run 10psi so not much over standard..