9a turbo build

[Shanect]

Hi guys I have a vw 16v 9a. I bought a abf head with t3t4 turbo and fitted it on the stock 9a bottom what is the safest boost with stock internals

[Jetta2]

Have you fitted lower compression pistons?
If not, do it before running any sort of boost through that motor.

[Shanect]

Is the 9a pistons gonna be a problem

[Jetta2]

Is the 9a pistons gonna be a problem

Yes.

9A stock compression ratio is 10.5:1 and is too high for any decent boost. If you are lucky you can get away with very low boost of about 0.2 or 0.3 Bar on that compression ratio.

And change the conrod bolts to ARP items as the stock rod bolts will decide to not work anymore. Not a case of if they will break, it is when they will.

[Shanect]

What would be a good piston to fit... I heard about Caravelle pistons pocketed works