how much psi should i run?

hey guys, im buying a procharger p600b from another stanger, im wondering how much boost am i safe at without splitting the block....hes giving me a 9lb pulley and the 11lb pulley the unit has on now and the kit is air to air intercooled...i dont beat on the car,or abuse it....i wanna run the 9lb pulley bcus i think i can make good power with it with maybe less pressure since i do have better flowing heads and intake than stock...what do you guys think? am i safe using the 9lb pulley with stock bottom end and block? how much power do you guys think i can i achieve with both pulleys?

ps....gonna have to look into an upgrade in transmission since im still on the stock t5:(
 
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the motor has 110,000 miles but its less, since i installed 373s when i had 80k miles....i have all the supporting bolt on and fuel mods, motor has tfs trackheats, eddy rpm intake, custom cam,double roller timing chain, gms hi perf. water pump, pioneer sfi balancer, 1.6rrs, 255 fuel pump, yada yada yada, etc. you get the point...see sig for numbers, on conservative tune......i had the car since it has had 30k miles....i take good care of it so im not worried about the condition of the motor....it looked SO GOOD when we had it apart down to the block.
 
Run whatever pulley it takes to get your car around 450rwhp. That would be the max I would say. Remember it takes power to run a blower. Also you might want to look into head studs. With head bolts I lifted both heads off the motor with only 8psi of boost. :D
 
Splitting the block? You could run more than that before that happens. Have you considered other modes of engine failure, like throwing rods and toasting the hypereutectic pistons or stock rings, bearings or crank?
 
Posted via Mobile Deviceoh of course! That's why I also asked what would be safe with the current stock bottom end.. I know those hypers can't take much...what's a safe amount that I can run without really worrying about damaging anything internally,including the block?
 
How important is it to you that you keep your motor in one running piece? Do you have the means to rebuild it if something breaks, even catastrophically? That's the question you really should be asking, not how close can I get to the limit.

If you can afford the rebuild with better aftermarket parts then go for the 11psi, otherwise go with the 9psi and a conservative tune.

What about driveline upgrades? Are you running the T5? How about the stock 28 spline rear end? These are other possible failures at your potential power level.
 
Why do you guys think the hyper pistons will explode at a certain power level? Geez at some of the crazy advice given in this section... The pistons will be fine and will last just as long as any forged ones will as long as you don't detonate. The rods also will be fine. This is why everyone that knows anything says "don't worry about the internals, the block will split before anything else". Just get a good tune and enjoy your car. Don't beat on it alot and you should be fine.

Now one thing that came to my mind is I also cracked 4 rings in the pistons when I was @ 8psi and 480/507. My car had 130k miles on it at this time. I burned so much oil that it looked like I was spraying for bugs.
 
Why do you guys think the hyper pistons will explode at a certain power level? Geez at some of the crazy advice given in this section... The pistons will be fine and will last just as long as any forged ones will as long as you don't detonate. The rods also will be fine. This is why everyone that knows anything says "don't worry about the internals, the block will split before anything else". Just get a good tune and enjoy your car. Don't beat on it alot and you should be fine.

Now one thing that came to my mind is I also cracked 4 rings in the pistons when I was @ 8psi and 480/507. My car had 130k miles on it at this time. I burned so much oil that it looked like I was spraying for bugs.

+1 seriously i read hyper are stronger than forged, just more brittle. the tune is the key, no doubt about it
 
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The reason I ask what's the limit, is so I can stay the hell away from it! LOL that's why! I have plans for an aftermarket block build perhaps in a couple of yearas so I would like to have my current motor reliable till then..like stated before, I don't beat on it or dog it for that matter..ohh I also talked to my tuner and he said I should be fine with the 9lb pulley...he says its all about the tune:)
 
Splitting the block? You could run more than that before that happens. Have you considered other modes of engine failure, like throwing rods and toasting the hypereutectic pistons or stock rings, bearings or crank?

"You could run more than that before that happens."

Or not ..... Blocks break at that HP #. Who cares if Joe blow ran his for a year like that. I am not being a wise guy but why would anyone run these cars so close to their limits? Budget? Ok, fine. But if you want to run that high then be prepared for breakage. hypereutectic pistons are not the concern with a good tune. This is internet rumor.
 
I had a 95GT with a HCI and a P600B and a 3 core intercooler. That car made 12-13psi and held up just fine. 5.0L's are tougher than people think. Splitting a block or detonating it is all in the tune. You must have a safe tune and the correct octane for long life. I ran mine HARD at the track and street and nothing ever happened to it. The stock T5 lived behind that too.
 
well, the way i see it, im gonna run the 9 psi pulley....with better heads, intake than the previous owner, im not gonna see the 9 psi, probably like 6 psi....im aware of what can happen if i get to the limit of the block and the possible failures of the stock internals and drivetrain parts......the rear end im not worried about, its not stock anymore.....my t5 has been taken care of and i dont powershift or beat on it...i know once im boosted, my tranny will be on borrowed time, im aware of that and will take care of it.....i wanted to know at what psi i was safe....that question was answered allready by my tuner.....know how much hp do you guys think ill make with the said 9lb pulley?
ohh, i doubt ill blow a head gasket with 6lbs of boost, but who knows, everybody has different results, if it happens ill take care of it
 
6psi will be barely noticeable. Even if you do a feel a difference, it will be minimal. Plus...you are gonna want more. Just go with a pulley that will "Net" you 11lbs and you will be happy for the rest of the summer. If the tune and octane is right, it will live.
 
Why do you guys think the hyper pistons will explode at a certain power level? Geez at some of the crazy advice given in this section... The pistons will be fine and will last just as long as any forged ones will as long as you don't detonate. The rods also will be fine. This is why everyone that knows anything says "don't worry about the internals, the block will split before anything else". Just get a good tune and enjoy your car. Don't beat on it alot and you should be fine.

Now one thing that came to my mind is I also cracked 4 rings in the pistons when I was @ 8psi and 480/507. My car had 130k miles on it at this time. I burned so much oil that it looked like I was spraying for bugs.


read about a guy in Hot Rod magazine that had a 93 fox w/ a 97 mountaineer engine w/ E7 heads, GT 40 intake, flows and home made twin turbo's pounding the cast pistons, rods and crank w/ 14 PSI and up that that point had made 187 passes on it at the track. T5 Tranny and 28 spline axles...... go figure.
 
read about a guy in Hot Rod magazine that had a 93 fox w/ a 97 mountaineer engine w/ E7 heads, GT 40 intake, flows and home made twin turbo's pounding the cast pistons, rods and crank w/ 14 PSI and up that that point had made 187 passes on it at the track. T5 Tranny and 28 spline axles...... go figure.

I've actually witnessed a Fox body with probably 700-800rwhp on a bone stock motor lasting for a good while. Finally the block did split. By myself along with everyone else thought he was full of it and had a Dart or mexican block with internals. I believed it up until I helped him pull the motor out of the car. He made me notice that it infact was a bone stock shortblock. :shrug: I wouldn't push it that far but I won't say it can't be done.
 
There is a guy in Texas with a black SN-95 putting down 900rwhp on a stock block and a turbo. Not sure how long it will last, but it's not impossible to do.

Kurt