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Ok, I was thinking about turboing my 94 RS. Does anyone know if the CR on this car needs to be lowered for the turbo, and if so, how?
Is it better for the compression to be lower or would a slightly higher ratio be better?
I also heard that it would be a good idea to have titanium valves installed for the turbo application as the regular valves could get scorched by the higher temps. Does this have any merit?
I am having the heads redone and flowed also. I thought I would have them installed, but if it is not necesary, I won't.
Thanks in advance !!

you dont need to lower the compression at all. it just makes it easer to tune, meaning more room for error at a lower compression. and the stock motor at 9:1 i wouldent even worrie. if your that worried about it you can get B6T pistons which are 7.9:1. you will make a decent amount more power with the 9:1 though and it will handle the boost up to 10 psi with no problems as long as your A/F is tuned properly.

with the valves. the stock ones are plenty fine. who ever told you that is full of it. they will work just fine. you should never have a problem running a turbo on them. and sodium filled valves would be the way to go if you went with aftermarket valves. so its not nessary but it would be a little safer, but i would only do it if you went to 3 angle valves.

if you were to get aftermarkt valves, stainless is the best choice IMO. sodium filled valves are good to a certain point, but i'd take stainless over them anyday.

id lower compression anyways to run boost without having intercooler you want lower compression achieved by installing different pistons (preferrably forged)

thats not always true, im running 8:1 wiesco forged pistons. and without the intercooler it pings like crazy in the high end. with 8psi and 460 injectors. put the IC on and never another problem.