I just bought CTR pistions for my 99 GS-R motor
I was curious to know if there were any compression problems and wanted to see if any one else had tried it before

 

search in the all motor forum. you'll find more than enough info.

 

Just curious...why did you buy them? Do you have any idea if the CR will be ideal for your build?

 

he compression is gonna be high and you gonna need to pump race gas. shoulda just went with the itr or b16 pistons

 

There would be no compression problems. Ctr is about 11.6-1 cr so you would be close to 12-1 in a gsr motor... hence you should be using at least 91-93 octane gas.

The problem is that ctr pistons have a higher dome so the pistons will be hitting the valves. You would have to get the head checked for clearance.

 

Yeah, it'll be like 12:1. But why the hell did you buy pistons before knowing what you want?

 

my friend has them in his ls/vtec....made great power gains, just used 91+ octane

 

your gonna need to take them to a machine shop and have them milled down a bit , not even a milimeter. factory , the compression height of CTR pistons is 30.73mm. they need to be milled to have a compression height of 30.10mm. this will give you piston to deck of .032". GSR stock is .034". CTR stock is .026". youl have approx 12.1:1 CR.