Warning I’m a Newbie: Aftermarket BOV question.

[DonFrijoles]

Hello
I’m am very new to having a vehicle with a turbo and have seen the aftermarket BOV valves and was wondering if I have a stock setup(no tune) and just an exhaust will adding a BOV be beneficial or will it wear down my turbo? Or what will it do? My ranger is a daily driver but wanted to give it some “street cred” if you will.

Disclaimer: I used the search function and I got topic results where folks already know what they are talking about and didn’t find an answer for my scenario.

Sponsored

 

[mobilemike01]

You’re not going to have any extra wear. All the BOV will do is give you some sound. I had one in my Focus ST and it was cool at first but got annoying after a while.

 

[DerangedPony]

An aftermarket BOV will have zero effect of performance or wear. If you were adding a bunch of extra boost, there can be something said for an aftermarket BOV holding a higher boost pressure better but it's not an issue anywhere around stock level.

That being said, I have the Turbosmart BOV. Under normal driving, there is not enough boost to open it all the way so you can't hear it. When you get on it, you can hear it but it's not super loud so it's a good mix.

 

[DonFrijoles]

I figured this was the case, thank you guys for the reply and tolerance of a newbie question lol

 

[MannyS]

Won't a BOV that releases into atmosphere cause the engine to run too rich?

 

[weasel1]

As I understand it, it dumps excess air, as in when you close the throttle body. So, the engine wouldn't be using that air anyway.

 

[MannyS]

As I understand it, it dumps excess air, as in when you close the throttle body. So, the engine wouldn't be using that air anyway.

But there a sensor that measures the air that is going to the engine. And what that sensor does is adds or takes away fuel going into the engine based off the air going in. So the sensor will think the engine is getting air it's really not. This making it run rich.

 

[weasel1]

But there a sensor that measures the air that is going to the engine. And what that sensor does is adds or takes away fuel going into the engine based off the air going in. So the sensor will think the engine is getting air it's really not. This making it run rich.

Not quite that simple. Under and overpressure condition (rapidly closing the throttle body) the excess pressure has to go somewhere. In a factory system, it gets returned to the intake of the turbo. Throttle position sensors will indicate to NOT keep adding fuel and run rich. A BOV just dumps that extra pressure into the atmosphere instead of potentially stalling the turbo compressor. I'm sure there are other sensors at play, but that's a much longer conversation.

 

[DerangedPony]

The stock BOV recirculates the unused boost back to the intake before the turbo to try to spool the turbo to reduce lag. Either way, if it's done this way or to atmosphere, the engine knows not to account for that air and to wait for the BOV to close and to see what boost happens next.

 

[MannyS]

Not quite that simple. Under and overpressure condition (rapidly closing the throttle body) the excess pressure has to go somewhere. In a factory system, it gets returned to the intake of the turbo. Throttle position sensors will indicate to NOT keep adding fuel and run rich. A BOV just dumps that extra pressure into the atmosphere instead of potentially stalling the turbo compressor. I'm sure there are other sensors at play, but that's a much longer conversation.

Feel free to read the whole thing. But scroll down to Walters explaination.

https://themotorhood.com/themotorho...-need-a-blow-off-valve-we-talk-to-the-experts

 

[DerangedPony]

Feel free to read the whole thing. But scroll down to Walters explaination.

https://themotorhood.com/themotorho...-need-a-blow-off-valve-we-talk-to-the-experts

He's talking about MAF, our Rangers use Speed Density.

 

[DerangedPony]

This may help why it doesn't matter on our engines:

https://www.boostedperformancetuning.com/speed-density

"What it boils down to is using the manifold pressure sensor (MAP) and intake air temperature (IAT) sensor instead of the MAF sensor to calculate the amount of air entering the engine. These sensors take their readings right as the air is actually entering the engine so they are not affected by the things that cause issues with the MAF sensor. "

 

[outdoorphotog]

Won't a BOV that releases into atmosphere cause the engine to run too rich?

Only with a MAF sensor, not with a MAP sensor. MAF needs BOV release to be recirculated, MAP does not.

 

[outdoorphotog]

This may help why it doesn't matter on our engines:

https://www.boostedperformancetuning.com/speed-density

"What it boils down to is using the manifold pressure sensor (MAP) and intake air temperature (IAT) sensor instead of the MAF sensor to calculate the amount of air entering the engine. These sensors take their readings right as the air is actually entering the engine so they are not affected by the things that cause issues with the MAF sensor. "

You beat me to it lol

 

[Mobius97]

Do our stock systems have a BOV? I haven't bothered to look TBH but I don't hear one. I was under the impression that it is a diverter valve since it doesn't dump (VTA) but instead recycles the metered air back into the intake track. I've ran both in previous turbo vehicles but found that I would get stumbling/idle issues when just switching from a stock BPV to a true BOV w/o doing anything else, just a straight swap. So what I did is went with a hybrid model, like a Forge Motorsports one to still get some of that pssshht sound some folks like and not worry about it.

Things change so I may be off as this is my first T/C vehicle in a long time. My current F/I setups over the last decade have been supercharged.

Sponsored