you can't just put the ls rods in there, you have to do the crank too. I have an ls crank you can get. i'd probably do p30 pistons instead of the ctrs just cuz on a full gsr it makes the cr a little bit too high for pump gas without a really good tune. and imo the itrs in a gsr just dont bring the cr high enough....pm me if u have any other questions or if u need someone to build the motor for u.
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