Hi Neil.
My setup is similar to you, mongoose, intake etc.
Are you not using any sort of boost control at the moment? Grainger/MBC?
As everyone say's you're just taking the boost over the fuel cut level, perhaps with a little spike.
Some good boost control would stop this, I use a ebc
(blitz sbc-id) and with this I can raise the max boost bit by bit until it's just below my cut point which is about 18.6psi on my car.
Now I never trip it.
I reckon thats enough boost anyway, and If I want more power now I need to go bigger turbo.
My engine had a fcd on it when I bought it, but I removed it as I prefer to have the protection of the cut.
Remeber that Rev 3's determine fuelling of this line, Not a problem on Rev 2's with their AFM's.
As I think I think I see it
(somebody please correct me) the boost line
(PIM) is simply a proportional fuelling line where
(say) 0V=0% fuel and 4V=100% fuel, 4.1V= fuel cut.
Now if you clamp it to 4V, you're removed the cut, and can run boost above the point where the MAP sensor produces
>4.1V.
I belive there is enough fuel at fuel cut point for a little more boost, but how far you take it past that point if you do use a fcd is better found out by a tuner who's watching the EGT etc
I've also got a Unichip for ignition and fuelling only
(not boost control) but the changes this makes were more in midrange, not really higher up, fuel higher up was left relativly unmodified.
Go for some good boost control, dosent have to be a ebc, and if fitting a fcd, have the max boost level set up by a tuner who looking for underfuelling.
Andy
