I am in need of new pistons for my 1.8 turbo motor. The stock low (8.to1) compression pistons are not available in the US. I can get factory pistons from Alfa Romeo and have the shipped for $1300 or have them made by JE pistons for $720. This is a lot of money. My other option is to buy US available non turbo pistons, liners, rings and wrist pins ready to install for $500. But they are 9.5 to 1 CR. My question is, if I run 5 psi and an intercooler will I really be asking for trouble?

 

All is in the tuning...

 

give us some more details about your ride and whatnot. 5 psi is nothing and your gonna get boost happy.

 

9.5:1 is fine, go with it

 

The car is a 1969 Alfa Romeo GTV. I bought it as a shell and have been putting it together for the past 7 years. A friend gave me a 1.8L turbo motor from an Australian “75” series coupe. The block and head are very similar to the original motor also a 1.8L. But I had to build a custom intake manifold and make many modifications to the exhaust side. I am using DIY Megasquirt fuel injection system. I had the car running and had been tuning it, I am currently running 5 psi boost and the car was running fine. But this Saturday I turned it on and it started to smoke. The spark plugs for Cyl 1,2 and 3 look OK, but # 4 looks oily. The head was just rebuilt. So I did a leakdown test, and found # 4 rings to be leaking, and so my dilemma.

 

Best avatar on HMT.