Hi Guys,

quick question i was wondering what highest sort of safe boost lvl my E8 can run.

Mods in my sig, below is a chart @22.5-23.5psi of boost, ive seen guys running into the 25 odd psi.

opinions?




Also the numbers are un-corrected smoothing of 5, DynoJet average

 

Depends on how the car reacts really, and what octane gas you can get...

 

well im in AUS and run 98oct but i believe its about US 92-94

Does head studs come into play when increasing boost?, or can i just increase boost while i keep making power and no knocking?

 

Im running 6262 @ 30psi on 93oct, stockblock and no headstuds. I think headstuds is more for the safety aspect. Im pretty sure I can say that there are alot of people on here that are running atleast 30psi on their stock blocks aswell.

 

Ok cool ill crank it up a little more, about 25psi and see what sort of gains i can get.

I think stock cooler is gunna start holding me back now correct?

 

Im currently running 30 psi on a stock 8 turbo with basic intake and exhaust stuff. No studs or anything and it runs like crazy. You could get away with 25psi no problem on your fuel. Just keep afrs in the 13s in spoolup, 11.5 in boost tapering to 11@ redline.

 

I'd say you'll probably be limited to about 25psi of boost as it looks like you only have the stock fmic. Thats where i am at until i get one as well as at 26psi it got heat soaked badly

 

Yeh i was thinking the cooler is going to hold me back at this point.

I think ill up to about 25odd, get a cooler and 02 Dump and increase it some more

 

Another thing i notice with my car is i get crazy boost taper, like at the moment i hit say 22psi then it quickly falls back to like 17 by redline, is this normal?

I think this could be due to the AEM Truboost,

But i have my crack pressure set low, which is supposed to stop tapering boost, so i dont know

 

26 psi, stock 9 turbo, stock headstuds, 91 octane here for last 40k miles.

 

Sweet ill crank it up a little bit then,

Anyone know the reason im not holding as much boost at redline, no boost leak either ive checked