i have a itr block that i want to boost don't have the money to get after market piston right now, i want to know will the ls piston fit am i going to have any clearance problem and how much boost would be safe.i got a gsr head a t3/t4 my goal is 300whp.

 

Why waste money to rebuild/assemble a bone stock motor with cast piston? If you cant afford a $450 set of pistons you shouldnt be boosting a motor. You can make 300whp easy with just an used LS Block with your GSR Head, which is probably the smartest thing for you to do.

 

the thing is that the itr need new rings and i was just going to replace them but i got a deal on a turbo kit from a friend and i have some ls piston.

 

save your money and wait till you have enought to do it right the first time. If not your just wasting time and money