just fitted my blitz bovs which are on hard pipes and tested it and i was running 1bar now its only got about 9psi the boost gauge reads nearly 10 but slowly goes down. and it seems to have a pop from the exhausts when changing gear .

 

does this sound like i got a vac leak,i cut off the vac lines to the re-circs and bung them up and put the other end on the bovs.

just fitted my blitz bovs which are on hard pipes and tested it and i was running 1bar now its only got about 9psi the boost gauge reads nearly 10 but slowly goes down. and it seems to have a pop from the exhausts when changing gear .

 

does this sound like i got a vac leak,i cut off the vac lines to the re-circs and bung them up and put the other end on the bovs.

 

 

been reading up on this do i have to adjust them to suit my car i.e 1bar .

make the spring more harder??

I believe so, tighten em up to tension the spring i think.

bump anyone else on this.

 

just cant work out why the exhausts would pop now???

my exhausts pop and i have bovs on mine mate

sounds like they are letting go too early so not holding full boost

my exhausts pop and i have bovs on mine mate

 

 

ok just didnt do it before hand

Reason you get the pop is :-

 

When you have recirc in place, All the air in the intake system has been metered by the AFM as it went through it, and the fuel calculated for this air. When the BOV recircs, the air passes back into the intake system so the ECU has already calculated the amount of fuel for it.

 

But, when you vent to Atmosphere, that air no longer goes back into the system, and the ECU has already made a fuel calculation for it. This results in you running a rich mixture during shifting and cuases unburnt fuel to explode....

 

 

As for the BOV, Tighten it up until you hold boost and you dont get compressor surge during shifts.

 

HTH

 

Marty

Reason you get the pop is :-

 

When you have recirc in place, All the air in the intake system has been metered by the AFM as it went through it, and the fuel calculated for this air. When the BOV recircs, the air passes back into the intake system so the ECU has already calculated the amount of fuel for it.

 

But, when you vent to Atmosphere, that air no longer goes back into the system, and the ECU has already made a fuel calculation for it. This results in you running a rich mixture during shifting and cuases unburnt fuel to explode....

 

 

As for the BOV, Tighten it up until you hold boost and you dont get compressor surge during shifts.

 

HTH

 

Marty

 

 

 

update.

 

adjusted the screw and still no 1 bar still about 9 psi to 10psi so i removed the bovs and put back to normal with new vacuum pipe and got 1 bar again.going away now until monday so going to look at again when i get back.think its a vac leakgoing to order some nrew vacuum pipe and hose etc and try again

Get a MAFT..like ive worked on dsms alot and whenever we went from recirc, to venting the bov, things like the car idled different, ran different, til we put on a mass air flow translator.

MAFT has no support for the VG30DETT last time i checked the full Throttle site.

ok well i didnt know if it did or not, was just a thought.

Yeah had done some reseach of the MAFT as its prolly the best piggy back for the mk3 Supra, for the VG30DDETT only viable piggyback options are Emanage Ultimate Running Speed desnity mode and the good old tried and tested VPC. Though both a bit OTT for standard tuning levels.

VPC? not used to some of the abbreviations. lol its probably something simple that id know if i thought about it but im burnt out right now, neeeeeeeed sleeeeeeeeep lol

HKS vein pressure Converter, Old bit of kit, that does away with the AFM. MAF and converts to Speed density (pressure). No longer made, is regarded as old school equipment, but does a brilliant job.

I see, thanks for the explanation

My Apexi SAFC II has an option for running with BOV's that made it run better and stopped a stalling problem I had when decellerating fast up to junctions etc.