I know what a block will take HP wise and what not. I don't want to ask " How much HP will this combo make ?" because I hate people that ask that. Just go to the track and find out. Well, it'll be a while before I can go again, and I need to do some tuning. Basically need to know if I stand a chance at breaking the block with 8 psi until I can make it to the dyno. I saw a fellow classic with nice heads make 530 RWHP with 5 psi. So it kinda scares me with mine set at 8. It has AFR 185's and a F-cam and is a 302. It feels faster at half throttl than the 100 shot sis at WOT. This is what scares me. As long as it is agreed I am safe at 8, I will conintue with the tuning at 8psi

 

i was running 7psi on a stock block, heads, intake, etc with no problem what so ever...124k miles

 

i don't think anyone can tell you if you'll break the block at 8psi vs. 5psi as boost psi is relitive to restriction not airflow. someone could be making 20lbs of boost and still not have the same efective air flow as someone making 8lbs.

 

hybred has it right....for instance I run 15pri of boost and make just under 750hp at the wheels....400 inch motor and two t60 turbo's...Now I can turn the boost up and make a ton more power but then I really start to tax the flow of my cold side piping.....inturn a buddy of mine has to run 10 psi to see the same power from just one T88 turbo, his cold side pipes flow tons more than mine and when he pumps up the boost you really see that mother make power...It all about efficentcy(SP) and flow rate of your total system in and out that makes HP/TQ.......
Later
BK...

 

how does he make that more efficiency? by running small or larger cold piping or something along those lines you get better effieciency?

 

His piping had less radical bends in it. Also we built some expantion sections leading into the intercooler and out of his cooler...Then we tested how much back pressure we had in those areas and found that it was less than mine...My bud also has a slightly different port job on his heads and intake. I think that most off his improvements are due to how we piped his cold side we tried to make it as straight as possible and when we did make bends we did them like the exhaust pipe on a dirt bike....Looks cool and must work!!!!
Later....
B

 

I know this. That is why I have the question. I know a stock 302 with 10 psi sees around 440rwhp. But with the f-cam and the heads is where I am afraid the thing might make too much at 8-10. That being said, with the amount of air being moved because of all the aftermarket junk, my 8psi will be different than a stoker with the same boost. I know what te thing makes with a 100 shot. But people with experience as far as this goes, 8 psi shouldn't be too much to start with ?

 

expantion sections? do u have any pics?

 

Set it low 2-4 psi and run around with it until you get to a dyno and tune it. . Believe me you don't want to be apart of the blown gasket club. Of gone one level higher and be apart of the blown motor club (with attendant carnage pictures).
-bix

 

Question for yall what about amoter with 148,679 miles how much boost

 

setup?

 

Just an FYI. I'm running 14 lbs on a mpt70 on 94 oct with a 112k stock cobra long block. This thing sees full boost 2-3 times everytime I drive it. Stock motors can take alot of abuse. It's all in the tune. BTW I trapped 120mph at 10psi. At 14psi I can't even get on it until 4 gear because third scares me sideways.

 

It's not so much a matter of "how much boost" as it is "does the tuner know what he's doing?" I ran 13 psi on a bone stock 1994 shortblock with 100k miles before 3 pistons left the party early (about 530-550hp at the flywheel). However, I had no block problems. On the other hand, if a monkeytard is responsible for the tune, then it's entirely possible to drive over the crankshaft with "only" 8 psi.

With a good tune, you can run at least 13 psi in my experience, and not affect the block. More is possible, but I haven't personally done it.

Mark

 

lol great analogy...

a friend of mine was running 13psi on his engine ( stock longblock, ported GT40P's TB and eddy RPM manifold) before he started having serious problems, such as head gaskets and leaning out and what not, and eventually he put 15psi to it and then the real fun began, involving a broom and a dustpan in the middle of the track...

 

Not running boost but nitrous and I was trapping 111mph in the 8th with my stock 93 shortblock, also with 1.39 60fts

 

Boost doesn't kill a block. Horsepower does.

 

No, its usually detonation that is the killer.
HP is ~relatively~ safe with no detonation.

 

Guys, all this I know. What I am getting at is that I understand that boost is relative. It's not like a 100 shot. You add a 100 shot and that's more or less what you get. I guess I'll just have to see if 8-10 is too much the hard way.

 

Guess it depends on what size turbo your ising. 10psi isn't just 10psi, it depends on how much cfm your craming into the motor. With some T-28's I have seen those push around 12psi on a street car and it held up great.