Low comp pistons in 1.8T

[bmarshall]

Hey all does anybody run low com pistons in there 1.8T or 2.7TT for that matter?
If so what boost are you running and how is the low engine speed performance?
Im getting 8.5:1 JE pistons for my rebuild with SCAT rods from 034.
Im doing so for a future BT high boost setup later down the track but going to use a K04 or SP51R-029 setup at the moment.
I might play around with pressures using an eboost2 to see how that goes with pinging etc.
Does anybody running above 15psi get probs with pinging on a standard engine setup?
What are some of the higher boost levels people run with K03/K04?
Cheers.

 

[aragorn]

You can push the standard 9:1 compression ratio quite far afaik.

I'm sure JCB on here has built a GT2871 2L stroker and is running that on 9:1.

 

[jcb]

be 9.2:1 now. Head and block was skimmed.

no need to run super low comp pistons. You will suffer badly with lack of torque and power off boost, especially on the breathless 1.8t. Fine if you are running a close ratio box in a stripped out racer but daily it would **** me off.

advances in engine management, knock control and cooling don't need the low comp, big lag engine builds to counteract Pre-Ignition or detonation that we grew up on. (sorry, major assumption. let me rephrase that......old feckers like me grew up on!)

20-30 yrs ago you wouldn't find a turbo engine with more than 8.5:1 now they run 10:1 with good parts and management