Hi, Ive got a D1 Procharger for the 2008 5.3 Sierra. Its going to be running at 12 psi, from what Ive heard and what procharger said is that its too much for a stock engine to handle and I would need to forge the internals and lower the compression.

Well the question is, it is possible to get a bigger pulley and drop it down to 7-8 psi and run it safe? And if so, what size pulley should i get? The current pulley size is 4.1 ..

Thanks for any input.

 

its all in the tune... just ask ricky(synergy)... he is running a truck load of boost on his 5.3 and just dynoed well over 700hp...

 

to be fair Rick has a full service shop and the ability to just pluck that little 5.3 out at anytime. Running 7-8lbs is going to be a lot safer than 12lbs for sure, not to say it can't be done, and yes, tuning is going to be the key.

 

Do you know if thats on a stock engine? Forged?

 

Well, Yeah I want to run at 7-8 psi but im not sure about the possibility of putting in a bigger pulley to do the trick, along with the tuning ofcourse. Or is the pulley not needed at all?

 

Rick's twin turbo 5.3 is a stock bottom end with 317 heads and L33 pistons.

 

the engine can take it just fine if it doesn't knock but 12psi is probably too high for 92 octane pump gas to not knock.

 

well 98 octane pump gas is available here, should that be good enough?

 

where is here? if it is really 98octane, the r+m/2 stuff then yeah i think it would be good enough. you are going to want to watch the tune very close for awhile and make sure there is no knock. starting at 12psi seems like a bad idea to me. 7-8psi for awhile and then steping up to 12 with the 98octane later seems like a better way to go.

 

Dubai..

Yep, seems like im going to be starting off with 7-8 psi