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Want to be clear from the start, I am not wanting to start a debate about VTA vs plumb-back BOVs.

My situation is, I am about to get some custom intercooler piping made from cooler to throttle-body.

I have a MAP-sensor based ECU & currently have a VTA BOV. However have hardly driven the car since the ECU was installed (due to problems, hence the new intercooler piping...) & don't really know what the BOV sounds like.

Have GTR cooler piping (getting changed anyway but to similar design on cooler side) with BOV down in inner guard so can't be seen & if it's quiet enough I was going to keep that on for now.

However if its too loud or whatever I want to change to GTR BOV, but don't want tune to be affected whatsoever (when backing off, etc)

Basically I'm wondering if the car is tuned with VTA BOV & I then change to GTR, etc plumb-back (or vice-versa) will tune be affected at all?

I know that using an AFM with a VTA BOV causes problems (been there...) & using a MAP-sensor with VTA is OK but is this because air being released by BOV is accounted for with MAP tune or what?

Cheers,

Brett

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no . it will be fine . with a map the ecu doesnt know/give two stuffs what you do with air outside the plenum . the ecu runs purely off the pressure between your throttle body and your intake valves , what you do outside that the ecu doesnt even know is happening

  • 2 weeks later...

I have a question to any gurus and fellow members out there if can help,

I just bought a 32 4dr and is a very good tuned street car and runs a upgraded fuelpump n turbo (rb25det turbo @13 psi) and tuned power fc with hand controller.My question is will blocking up the standard bov for flutter :) (previous owner kept it not aftermarket 1) "throw out" somehow or interfere with the power fc tune or not..

Cheers :P

P.s i posted this b4 in a difrent section (my bad) and think i pisd off sum peepz

you may find it will be sluggish / doughy on gearchange

youll find your tuner has accounted for the missing air in the tune (when running atmo and close the throttle body) and you may find that will be dougy/sluggish on gearchange/close throttle body. this is because your tuner has accounted for the air being vented out of the system. and depending on where your map sensor is placed how it may impact the tune.

i would expect some affect going from a tune based on vent to atmo setup vs recirc as now you "extra" air in the intake system which wasn't originally planned for

  • 4 years later...

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