how much boost

[gsxrturbo]

Ok I have a ecs Paxton on e85 and I see I am peaking 14 psi,on stock engine and headers,fore daul pumps,think dare go more boost or stop where I'm at,755rwhp631 torque

[QUICRNU]

I am no expert here, but I am curious... I am on 11.5 lbs (peaks at 12 on the finish line) with an LSA stock bottom end (ARP head bolts and LS9 gaskets)

I had always heard 12 was a little pushy on stock pistons?

*Shurg*

[mrimpala02]

I don't think a certain psi matters as much as the rwhp. I'm at 815 rwhp on a mustang dyno @ 16.5 psi. I have a turbo specific cam so it tends to allow more boost to build from what I've seen when compared an NA cam.

I think most would say 800 rwhp is relatively Ok with good tuning.

[sprayedv]

Originally Posted by mrimpala02

I don't think a certain psi matters as much as the rwhp. I'm at 815 rwhp on a mustang dyno @ 16.5 psi. I have a turbo specific cam so it tends to allow more boost to build from what I've seen when compared an NA cam.

I think most would say 800 rwhp is relatively Ok with good tuning.

Rwhp means nothing.

People can run 16 psi and make different whp numbers.

I always went by on completely stock internals anything over 12 is starting to push it. Also depends how much WOT and what fuel/tune you use but I think 12 has been a pretty standard number through the years.

[CGbambam]

I'd crank it up to 18/20 psi on that blower, centrificals are so progressive in the power band you'll be fine. It's all about where your peak hp hits is what causes bent rods. That's why root style and big nitrous shot motors take such a beating because the power is instant not progressively. Much how a big turbo stock 4.8 can do 30 psi on stock internals because it doesn't even make boost till 6k rpms in the power band.

[JANNETTYRACING]

Originally Posted by gsxrturbo

Ok I have a ecs Paxton on e85 and I see I am peaking 14 psi,on stock engine and headers,fore daul pumps,think dare go more boost or stop where I'm at,755rwhp631 torque

Put a cam in and relieve some of that stress on the engine, you will likely pick up 75 RWHP with no other changes.

E-85 is very forgiving so you likely have more room.

Depending on which blower you have you may be at the end of it's efficiency.

You might need to step up the blower as well.

Ted.

[mrimpala02]

Originally Posted by sprayedv

Rwhp means nothing.

People can run 16 psi and make different whp numbers.

I always went by on completely stock internals anything over 12 is starting to push it. Also depends how much WOT and what fuel/tune you use but I think 12 has been a pretty standard number through the years.

Actually, the gauge pressure shown on a boost gauge is nothing more than a reference number. Cylinder pressure is more important figure than anything.

[sprayedv]

Originally Posted by mrimpala02

Actually, the gauge pressure shown on a boost gauge is nothing more than a reference number. Cylinder pressure is more important figure than anything.

Correct, for that reason I stated 12 is a pretty good number to know where your limits are at.

Every build and car are different but dipping into double digit boost is always putting strain on stock internals.

I have been running 10psi for 5 years on my SS and it has never given a problem.

[TRC-SS]

I found out the hard way that 13.5lbs boost was my limit.

[RealQuick]

I will be going for 900rwhp @ 16psi on stock bottom this Saturday... hopefully the clutch holds.

[mrimpala02]

All about the tune! And some luck maybe!