OverBoost cut

[scoobyman]

Good day,
Could anyone please tell me if its possible to cut power to the engine ( that would work like a rev limiter of sorts) in case of an overboost on a motec m800?

[stevieturbo]

Yes, and strangely it's called an overboost cut.

[scoobyman]

I'm sorry if i am being silly, i'm not blind, but i could not and cannot find it anywhere, could you please point me in the right direction ?

Also, i forgot to mention - i do not want the ECU to cut boost (it has to be an ignition or a fuel cut), because the thing that i am trying to safeguard against is a failure of EWG control.
I am using an air injector to control boost and when those guys go, they allow the EWG to stay shut from the turbo pressure itself, as they operate in an opposite way to boost control solenoids.

[Pavlo]

It's in Functions->Boost Control-> Setup

Stop being a man and look properly.

[stevieturbo]

If you want a nice safe setup ( after boost cut is implemented ), then dont use an air injector then. We're into a new century now. I thought it was mostly ancient cossies stuck with those ?

A decent 3 port, or better still 4 port will give you plenty of control and w/g pressure fault condition

[scoobyman]

Thanks guys, i will look into using a boost control solenoid instead of the injector as i have a greddy 3-port one lying around from another install, however, i am only using what my mapper installed (albeit in 2008) as he saw fit and i did not really have the experience or knowledge to doubt his judgement.

[Pavlo]

If you're using a single air injector, I've only ever used this where they are not energised to give minimal boost and increasing on duty at the injector raises the boost. I prefer a fast acting 3 port solenoid though, the MAC ones are very good the Greddy ones (same as APexi) is quite good too but a little slower and you will struggle with duty cycles below about 20% so keep the speed down to 15hz or so.