I started a thread earlier but got no reply. I have a fully built race head with standalone on 93 octane. I turned up the boost to 22 psi and wow it made a huge difference, dont know if I want to turn it back down just yet I want to know if 22 psi is fine with the mods I have.

 

We don't know your mods, but 22psi is fine as long as you are not knocking. You can run far more boost than that, but the thing that holds you back is knock...with meth and/or race gas, you can turn up the wick. On 93oct, 22psi usually causes knock, so it's as safe as what your logger tells you.

 

whats stock boost?

 

19 at peak

 

I run 22 everyday on 93, and 23 on 94 (love sunoco!)

 

stock is 19.5 and it's fine to run up to 21 on 91 octane tuning with safc and with better gas 22 is easy. however i do suggest tuning very nicely with say 21 and then turning the boost down very slightly for added assurance. cuz it's all fun until that one time and picture this with me now, you're rippin' out a third gear pull and POP from under the hood. that thot always keeps me in check.

 

05's are 20.3 peak, aren't they?

 

my 04 peaks at 20.4

 

Do you have head studs?

The reason I ask is that I boosted 23psi on 93 once today and wondered if this one time occurance would do any stock stud streatching.

Man I got to replace those dam things

 

^^Most people prefer upgrading with running even 21psi..so..maybe they would be good investment.

 

the peak boost will vary from car to car with mods nad temperatures and elevations because hte stock system isn't great at regulating rock solid boost.

 

I have meth/H2O injection on 91 octane. I modded my wastegate and have hit as high as 30psi on 9.8 turbo. It was a spike, but hits 28 regularly and tapers to 24ish.
I ported my hot side, O2 housing and Exh manifold when I 1st bought the car 2 years ago. I have a modded head too, (1mm over valves, springs, ported/polished). Stck bottom end (minus bal shafts).
I love my EVO!!!