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Hey all,

Yes it is another bov question, but not a gay one... lol

Basically the car was tuned with an atmo bov, now if I change it back to recirculate (using same bov) will it affect the a/f ratio as there will be more air going back into the intake then tuned for?

Thanks in advance,

James

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No leaks.

When I got the car it already had the atmo bov and was tuned with it. But I don't want the noise so hence me wanting to go back to plumb back. At the same time don't want to mess with the air flow. On top of that don't want to pay for another tune just to have it recirculated.

Edited by GT888

plumb it back. if your really worried chuck it on the dyno after and make sure afr's are safe. aslong as it wasnt leaking tho it wont change anything other than the massive overfuelling you'd currently get when backing off

plumb it back. if your really worried chuck it on the dyno after and make sure afr's are safe. aslong as it wasnt leaking tho it wont change anything other than the massive overfuelling you'd currently get when backing off

After plumbing back I have noticed that when going on high boost then backing off it revs out a little by itself. But that's only on high boost between 1-1.5 bar. I guess besides wasting a little more fuel it'll help me keep my revs up when shifting gears when racing lol. I have the Apexi turbo timer which has an a/f digital readout, but don't understand the numbers.....

Edited by GT888
After plumbing back I have noticed that when going on high boost then backing off it revs out a little by itself. But that's only on high boost between 1-1.5 bar. I guess besides wasting a little more fuel it'll help me keep my revs up when shifting gears when racing lol. I have the Apexi turbo timer which has an a/f digital readout, but don't understand the numbers.....

Your Apexi tt will be reading the stock narrow band O2 sensor so any information about afrs will be useless anyway.

^how do you know?

Adding a atmo bov to a stock tune makes it's run richer

So when a car inls tuned for an atmo bov Nd switches to plumb back why wouldn't it run leaner

You could explain yourself instead of posting like your mr know it all

^how do you know?

Adding a atmo bov to a stock tune makes it's run richer

So when a car inls tuned for an atmo bov Nd switches to plumb back why wouldn't it run leaner

You could explain yourself instead of posting like your mr know it all

They only run richer because air that has been measured is being dumped. Fuel is still being pumped in for the missing air, ergo a richer mixture.

No dumping of air, fuel amount is correct for air going into engine.

Simple

They only run richer because air that has been measured is being dumped. Fuel is still being pumped in for the missing air, ergo a richer mixture.

No dumping of air, fuel amount is correct for air going into engine.

Simple

But the car has been tuned for not having that air going back into the engine, therefore there will be less fuel in ratio when plumb backed without another tune to compensate... ???

depending on your driving style i would be checking the tune with a wideband, on a dyno its mostly on throttle then backing off, whereas on the road like climbing a hill boosting then backing off a little then accellerating, this will cause the BOV to release and change the mixtures,

if it was a drag car i wouldnt be too worried as its flat out all the way only backing off for gear changes.

  • 2 years later...

i have a quick question regarding my stock bov...

i recently ugraded my inlet pipe with an aluminum pbm pipe but it didnt come with a nipple to recirculate my bov. i wus wondering if it would be ok to recirculate my bov maybe into my intercooler plumbing? since the maf has already read the extra air from the bov ...would the car run normal as it did if i did the plumbing somewere else besides the inlet pipe after the maf?

i know this is an old post but this would help lots .

thank you.

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