Does the waste gate on a turbo only open after the turbo reached maximum boost ?
cheers. Mike.

 

No. IIRC it can begin to open lower than full boost.

 

the reason I am asking is I have a full decat exaust fitted and it's mot time so I will have to put the std exaust back on. problem is the APS SR40 turbo I have fitted does not have a combined apperture for the wastegate and the exaust so by fitting the std exaust I am blanking off the wastegate.
I will be taking it very steady to the MOT garage (under 2500 rpm) but I want to make sure that I do no damage on the way.

 

Bit extreme. Will the standard centre section not go on. Most go through MOT with just this on.

 

No the std section is 2.5" my system is 3".
Mike.