Hi CL,

This is my second post and once again, forgive me if I'm out of line ...

But i had a quick question about the 2JZ-GE VVTi engine.

My question is:

How high can i go with the Compression on the VVTi N/A engine safely if i'm boosting low, say about 10-14 psi max?
Planning to run on pump gas, 91-93 Octane.

I know stock Compression is: 10.5:1 and it can safely boost 5-7 psi with the right tuning.

I'm thinking of boosting my VVTi N/A but not going too high in the boost.
I'm trying to retain as much as N/A power as i can without going too high on the boosting.
My ultimate goal won't be crazy, around ~ 400 WHP but i'm more of a Torque guy.
i would like my torque to be as close as the HP number.

Any feedback would help.

Thx again

 

Bump. No one??

 

I highly doubt you'll find anyone that will tell you its ok to raise compression from stock and boost. If you want torque just slap on a smaller turbo like a gt30. It'll spool really early giving you fantastic torque.

 

I'm sorry.
I wasn't that clear on my description.
I was looking into lowering my Compression but at the same time not go as low as the GTE (8.5:1).
Correct me if i'm wrong but the GTE with 8.5 compression can handle well over 20 psi of boost.
I was looking more into the ball park of about 9.3~9.5:1.

The difference between the GTE and GE is about 2 numbers: 8.5 vs 10.5, keeping in mind i have a VVTi GE.

Having said that, now my questions comes into play
1. how much compression can i go with for about 10-14 psi of boost, and still have some NA power.
2. and GT30 is definitely a great choice. quick spooling is what i'm looking for with low end torque.

(I knew someone who was running 9.0:1 compression on an older GE-T and was making close to 600 WHP with only about 19 psi of boost.)