Trmachuno

Anybody know how much psi u can run safely on an intercooled turbocharger if the engine has forged internals, good fuelpump, good injectors,and the suspension, transmission, and rear end are built too? I'm talking about for everyday driving. Wondering this b/c a blow off valve keeps boostoffwhen u run at lowrpm's. And let's say uhave fun with the caronce a week or every 2 weeks. I here a lot of people with kits made to run 11psi from their manufacturers and believe there must be a higher amount of psi that u can run safely for dd. Thanx ahead!

8cd03gro

talk to fazm and get his opinion. He is planning on running like 16psi on the stock block or something like that...cant remember exactly. If you shim your valves to get rid of the valve float, you could be pretty damn comfy runnin 12 psi which will make more than enough power for a VERY fun daily driver (likely over 400whp), but you are gonna need to strengthen the tranny. With forged pistons + the rest of the drivetrain strengthened the engine itself could handle some big numbers.

chrisc

the PH turbo can easily put out more than 400rwhp, but your tranny is gunna go at about that mark. i would not do it unless you have a lot of back up money for broken parts.

Trmachuno

Not gonna do it. Just seeing what most engines could take f/i wise for DD. 12psi sounds like it then. And how would I build up the transmission then? Buy a new one or could a body shop/transmission shop strengthen it? And would I have to build up the rear end too then? Dou think the engine could take a 12psi intercooled turbocharger w/heads/cam/intake and supporting things for DD or is that too much power? Thanx for the help guys!

Buckman

At one point I was putting down very close to 500rwhp/525rwtq, obviously it didn't hold together long there, but it was fun finding the limits of the stock block. That was on about 13.5 lbs of boost and a 75 shot.
In my opinion the stock block can handle about 13 psi pretty comfortably (sans the nitrous shot!)and actually I ran that for most of the year, laying down 11.9 ET's.
Also, after consultation with PowerHouse I came to the conclusion that heads/cams combo wasn't really worth the bang for the buck factor unless you are really looking for that last thing to do.
It is the launches and stress that is going to be an issue for the trans eventually. After 9K miles (7k on turbo) my trans was still holding up like a top, but others with considerably more miles were seeing issues crop up. You may look into a trans shop that could "beef" up the trans to hold the power better, or could do a C4 swap.
In my opinion if you are looking for the ultimate 4.0 combo w/ built block, heads, cams, and high boost turbo then look no further than Rygen. He has the absolute best setup out there, hands down. If I would have stayed 4.0 I would have mirrored his approach.

fazm

are you talkin on a fully built motor? probably 17+ psi is safe and fun for DD.

on the stock motor, if u dont drive like a jackass, 12-14psi is doable.

Trmachuno

Really, 17psi intercooled with a built block. Cool! What's the max psi u could run w/heads/cam/intake and forged internals(all other components built to take it)? That's pretty interesting. I was looking into this stuff for a future project(my future DD GT, or me and my dad's future project 5.0). I know theirdifferent engines and stuff, so I justwanted to see what an engine could take for add. Thanx for all ur help guys! Great Info!

8cd03gro

you can't think of it as maximum psi. Different turbo's will flow better than others and be more efficient, so flow more air per pound of boost, then you have to take temps into account and think about the different intercoolers, etc. I wouldn't base what a gt can run off of a 4.0. With some good pistons the 4.0 can take a huge beating, even stock it is pretty strong. You are going to want to replace the rods on a 3v or 2v first and pistons while you are in there.

Trmachuno

I know, I said forged internals/built block for the car w/supporting things(beefed tranny, stronger rear end possibly, etc).

banka87

Hows the engine swap coming along, Buckman?