1.5JZ - what pistons?

[cresslux]

Ok guys,

i have done a lot of searching and googling, but no one seems to have the answer to the question im asking.

i have lots of 1jz parts and n/a 2jz as well, so i decided it would be fun to build a 1.5JZ.

NOW what i am asking is: will the 1jz gte pistions work in the 2jz?
the compression ratio of the GE is too high for my liking so i want to drop it a little, so instead of buying a really expensive thick head gasket, would using the 8.5:1 1jz-gte pistons work?
i have plenty of 1jz gte's i can raid for pistons, so they are free for me, i will just buy new rings.
so has anyone here done this and does it work? because it will physically fit, but will the compression ratio be usable?

cheers

[Sam_Q]

I hope you don't mind me asking but why the downgrade to the 1J head?

What about putting some turbo pistons in the 2JZ bottom end?

[cresslux]

All my gear bolts to a 1jz head, and I have a few lying around.

I am putting turbo pistons in. I was just asking if the 1jz pistons would suit because I have plenty.

[midnight_purple_GA70]

a stock 2jzgte head gasket is not very expensive and will drop CR to a reasonable level...

[NME308]

Hi there mate,
It appears the 1JZGTE uses pistons with 5.65cc dish and 1.3mm gasket to achieve the 8.5:1 compression while the 2JZGTE uses 16.8cc dish pistons with 1.3mm gasket to achieve the 8.5:1 compression.

Given the above scenario the 1JZGTE pistons in the 2JZ block with 1.3mm gasket nets 10:1 compression (11.1:1 with 0.3mm N/A gasket) with the other assumed correct factor being people claim to have measured both the N/A and Turbo heads as same CC's. Even the thickest cometic gasket of 3.5mm will only drop comp to 8.2:1...

Using the standard 2JZGE N/A pistons of 11.7cc dish with a turbo 1.3mm gasket would however provide 9.1:1 compression. A cometic gasket of 3.5mm compressed thickness brings this combo back down into what I consider reasonable turbo compression ratio territory. 7.7:1 comp being what I call reasonable for tripling the factory power output on pump 98 fuel without requiring unobtanium internals.

All the above information is garnered from a few different websites and some math as I don't have jz's lying around to measure...

Cheers,
Jason

[Sam_Q]

I can likely supply 2jzgte pistons for $45 each if that helps

[cresslux]

hmm think I might get a set of 2jzgte pistons and head gasket lol. the I know it's going to work.