85 740 turbo, at what PSI does the fuel cut out for overboost protection?

also what is max boost that is safe on stock system....?




I was driving today and my wastgate hose exploded and i overboosted pretty hard and hit the stock fuel cut (which i didn;t know existed but am very glas it does)

anyways car is fine just wondering how much PSI i was running because it was fast lol..

I don't know what the boost cut is on the 700s, but I'm running my car at 10-11 psi right now and I've had it to about 14 without hitting the cut.

interesting...

This thing was fast.... but it did not feel good hitting boost cut lol....

i hit 17psi at spike and held 15psi once for about 20 seconds

not sure what the cut off is....but i try to keep it right around 12-14...also it may be different for the 230 than a 23

ciao

I think its about ~11-12 on the 240s ... lol

weird apparently from what i have been reading there is no set stock fuel cut/boost cut... apparently there is an overboost feature which will kick in at some point though however but from what i can tell there is no set point.


I wonder what determines the cut then?

Pretty sure on earlier systems (I'm thinking anything up to '90 or pre LH 2.4) the fuel cut was still set by an overboost solenoid on or around the brake pedal. For intercooled cars its about 13-14psi.

On 2.4 cars, it was more the AMM being outflowed that caused the cut which could be anywhere from 15-19psi. This COULD be the case for 2.2 as well, but I'm not sure. Look for the overboost switch/solenoid around the brake pedal.

IF there is a leak or split in that hose though....