cpelton

what about a 4.8 at 10 psi i allready want to turn up my boost lol I gotta get the tune figured out before that tho, gonna start working on a 2 bar tune and probably methanol.

Raffman

iTrader: (9)

I think I'm going to keep it at 8lbs after all the input I've recieved. Even the tech guy at ATI said the stock cast pistons won't like 10 lbs but admitted the meth inj. would help it live. He said a cam change would net better results, so maybe down the road???

parish8

iTrader: (6)

with the proper fuel and tune the stock pistons are fine for 500+rwhp. with a stock cam that would be 15+psi. i have taken a stock 4.8 and 5.3 up close to 20psi. you have no room for error though. screw up your tune and it will break a piston quickly.

Spoolin

iTrader: (8)

Hey parish...you need to come out to Cali and tune my truck since I hope to be pushing 20 lbs. I figure getting you a round trip flight out here with a hotel would be cheaper than actually paying 650 for a dyno tune anyways!! Lol
What do you say? You wanna come see disneyland and take pictures with mickey mouse?
You could come to your June gtg!!

parish8

iTrader: (6)

hmm, if i could get some time off i might be interested but i have used up all of my days and more.

i dont want people to think that any boost level is ok with the right tune. it takes the right tune along with the right plugs and fuel and i am sure a few other things. if your only willing to run pump gas then the limit is lower than pump gas and meth. even with meth there seems to be a limit but maybe i didn't run enough meth. race fuel is nice stuff and lets you really push things but who around here is going to run race fuel all the time.

when i pushed the 4.8 and 5.3 it was with cold plugs, a decent intercooler and 100% race fuel. 118octane.

Spoolin

iTrader: (8)

Well the gtg is July 29th which is a saturday. Could fly you out Friday night after work. Play with my truck for half a day, run as much meth and 91/93 octane you wanna and still have time to go see mickey. Did I mention all the hotties we have at the beach during the summer that run arond in the latest non-exsistant thongs. Just a thought!! Lol

TURBO8

iTrader: (9)

LOL! I hit 25psi on the dyno with a good tune, 317 heads, stock block, meth, intercooler, and tr6 plugs. No signs of failure. (except a blown fuse) I run 18-20psi on the street.

99Silverado5.3

iTrader: (7)

Was this a BONE STOCK 4.8/5.3 that handled that much hp?

parish8

iTrader: (6)

bone stock 4.8 got to 496rwhp on a mustang dyno thru a 4l80e and tcase.

stock 5.3 other than a z06 cam and some good springs on a dynojet thru th400 unlocked. 600rwhp.

6.0 with a few more parts like cam, springs, rod bolts and head studs got to 640rwhp.

not sure of the limit of a stock motor since i have never found the limit of one.

Bill Reid

iTrader: (14)

well... I'm doing 10psi right now... in a daily driver in 110F ambient temps. I can hammer it repeatidly (I do use TORCO with 91 crap gas)... no KR... and nothing has broken... YET. My stock 4L60E is holding with its Transgo HD2 shift kit with Sonnax 2 and 4 servo... along with aluminum accumulators from Vince and Chuck at FLT. BTW, those guys are awesome. In a nutshell I am particularly sensitive to down time. If this motor lasts into the Winter... I'll leave the current spring in the waste gate... and I have no doubt I'll see 12psi

Bill