In a few years, I plan to build a civic hb race car. My setup will be a 96 hatch with a Greddy or Drag turbocharged B18C. My question is that after running the turbo on a stock motor for a while I will re-inforce my bottom end with better internals. Ususally a JUN setup involves high compression but for a turbo setup, I would want lower compression. What is the compression determining part in an all motor engine? Can I have the smooth JUN idle if I have a turbo setup. My top priority is a smooth idle and good driveability.

 

JUN does not offer a "turbo specific" cam yet. You might be able to use 1s or 2s but you have to be careful to not have to much overlap for FI applications. If you aren't planning to do this for a few years I wouldn't bother worrying. THe import arena has changed in the past 2 years and who knows what will be available in another 2 years. I believe JUN will have specific application cams available by then but you never know.

 

JUN 1's would be more for turbo. but i wouldnt go with anything more than ITR cams

 

Yeah, I was thinking that in a few years, there will probably be turbo specific cams and other parts required to strengthen the bottom end.

My other question was what exactly raises the compression? Anything that shrinks the volume inside the compression chamger will wont it? Do I need to alter the compression alot for the turbo setup?

 

Your choice of piston dome design (usually measured in cubic centimeters) will determine compression (along with bore and stroke). Most turbo applications use a non-domed (i.e. flat) piston head design in a compression ratio of about 9:1

 

I've often heard people favour crower parts for turbo motors. I thought crower were re-grinds and were of lesser quality.