squirlchasr919

Looking to possibly get a new pump sometime early next year. My question is how high an rpm is safe without risking engine damage? I know with the 4K GSK you need the stiffer valve springs, but what if you wanted to go higher, say 5K? Does the motor need some different internals? Cam, balancer, anything like that, also is there any real advantage to be had turning these things past 4K?
I'm trying to turn this truck into a sled puller and phase it out of daily driving duty.
Thanks for the help.

wana12v

for sled pulling rpm is benificial, the more wheel speed you can have the better. that is why the 3rd gen pullers are using such big gears (5th low) cuz they dont have the rpms 12v's have. For 5k you will need 60lb springs and hardened reatiners/titanium keepers (haisley has em)

oops I noticed you have an auto. I doudbt you will need 5k cuz you can shift. let it hit 4k shift and when it starts bogging depending on the track drop back down again, thats how all the auto pullers ive seen do it. If it'll spin out in third let it if not drop back to second