I just finish rebuilding my friends engine 4G63 and I used 4G63 n/t pistons because the have a higher compression 9.0:1 ratio which means less turbo lag. After we took it for a spin we noticed that the turbo kicked in much faster. The stock pistons have 7.8:1. And my friends engine is still running 12 psi. Good results

Did you do a compression test before and after? With that ratio, you're prolly around 190 psi across the board. What HG did you use?




-Tony
98'GST (soon to be neglected)
92'TSI AWD (soon to be modded) ;)

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turboclipz on AIM

I did a compression test it came out to 150 psi on all cylinders.

that compression seems low for the 9.0 compression ratio. My car had close to 170 across the board with T pistons.

People have used NT pistons in the 4g63t motors with very bad results. They are not the same metal. They will not withstand boost and higher temperatures. Come on, this is Mitsubishi. They will save money any way they can.

Enjoy that engine now, because the pistons won't last long.


Directly from VFAQ:

Has anybody ever installed 2G pistons in a 1G engine?
Has anybody ever installed 1G NT pistons in a 1G T engine?

This has been done on occasion. 2G turbo pistons are a higher compression ratio (8.5:1 instead of 7.8:1) and are capable of delivering more power, with a higher probability of detonation. The same should be true of 1G NT pistons (9.0:1), but the NT pistons are not designed to withstand the stresses inherent in turbocharging, making the 2G turbo pistons the next best choice.