Ford Mustang Ecoboost Forum banner

Opinions on a Blow Off Valve

26K views 7 replies 6 participants last post by  KewlWinter 
#1 ·
Hey guys,

First off let me start by saying sorry in advance. I recently got my Mustang a few weeks ago, so I am still learning a lot and don't quite know all the "terms" yet. So it'd be great if you could explain/be simple, I'd appreciate it!

I love the turbo sound on my Ecoboost, though I feel like a lot of the times it's pretty quiet or I just don't hear it at all. I've been trying to figure out what "Triggers" the whoosh, but I've mainly only heard it when taking off from a stop.

Then I heard about these Blow Off Valves, which makes the Turbo louder? I'm still not 100% on the mechanics behind it or how they sound. I've been looking around a little bit and I found 2 different ones on American Muscle for example. One is a Turbosmart Kompact Shortie Recirculating Blow Off Valve and the other is a Dual Port Blow Off Valve. If i ended up getting a blow off valve, would these somehow effect my PP Gauges too?

So I mainly just wanted to get everyones opinion on them and how you like them if you do, how they sound/work, recommendations, etc..!
Thanks in advance!
 
See less See more
#2 ·
There are several sources of "turbo noise" under the hood of an ecoboost. The first one you'll hear, when taking off from a start, is the intake. this is just the sound of the air going in. The second "turbo noise" you might hear is a whine from the turbo itself. This isn't usually audible from inside the car unless you've done quite a few mods first, like a downpipe and catback exhaust. The third noise is the whoosh of the stock recirculation valve. This is where the BOV comes into play. You'll only hear this whoosh when you let off the gas after being in boost.

A BOV doesn't affect power in any way, nor foes it have any effect on the PP gauges. Going with one of those aftermarket BOV choices requires you find a source of engine vacuum and bypass the stock valve that currently controls the recirculation valve. Instead of going that route I recommend the GoFastBits DV+. This is an upgrade to teh stock valve, that gets you more of the turbo release noise when you let off the gas, but still allows the car's computer to control that release of pressure.

I also wouldn't start with a BOV or DV+ change. I recommend starting here: https://www.mustangecoboost.net/thr...-new-to-modifying-the-ecoboost-mustang.18131/
 
#3 ·
There are several sources of "turbo noise" under the hood of an ecoboost. The first one you'll hear, when taking off from a start, is the intake. this is just the sound of the air going in. The second "turbo noise" you might hear is a whine from the turbo itself. This isn't usually audible from inside the car unless you've done quite a few mods first, like a downpipe and catback exhaust. The third noise is the whoosh of the stock recirculation valve. This is where the BOV comes into play. You'll only hear this whoosh when you let off the gas after being in boost.

A BOV doesn't affect power in any way, nor foes it have any effect on the PP gauges. Going with one of those aftermarket BOV choices requires you find a source of engine vacuum and bypass the stock valve that currently controls the recirculation valve. Instead of going that route I recommend the GoFastBits DV+. This is an upgrade to teh stock valve, that gets you more of the turbo release noise when you let off the gas, but still allows the car's computer to control that release of pressure.

I also wouldn't start with a BOV or DV+ change. I recommend starting here: https://www.mustangecoboost.net/thr...-new-to-modifying-the-ecoboost-mustang.18131/
Thank you, zhent!
 
  • Like
Reactions: gatornek
#4 ·
If all you wanna do is hear the blow off noise, you can remove the recirculating hose from the blow off back to the intake. Just make sure to cap the hole left behind on the intake tube. There should be plenty of information on here to help with that mod, I have it myself. Not to difficult to do, maybe 5 minutes.
 
#5 ·
The reason it's hard to hear the engine or turbo noises in our Ecoboosts, is also because the Factory windscreen contains "Sound guard".
If you look carefully at the bottom of the glass from inside the cabin (don't know about US cars, on on our Aussie delivered right hand drive cars the etched "sound Guard" logo is on the driver's bottom right of the screen)
The sound deadening acoustic glass stops alot of engine (and road noise) entering the cabin.
If you wind your side window down, you will hear the turbo a lot more.

That is why if you ever crack your windscreen, and get a replacement, a non-OEM one without the Sound Guard will be a lot cheaper than an original. :)

Also keep in mind that venting your BOV to atmosphere (to hear the whooosh), may be illegal in your state or territory due to emission laws.

In Australia where I live, its illegal and can lead to your car being defected by the police if they pull up beside you and hear the whoosh.
 
  • Like
Reactions: Jakester
#7 ·
No, the BOV won't change fuel mixture.
 
#8 ·
The functional reason to upgrade your OEM bypass valve would be to hold boost reliably. The OEM valve is know to leak at higher boost levels. The aesthetic reason would be for the sound. For the louder sound, you would be going from a bypass valve (BPV) which diverts back to the intake to a blow-off valve (BOV) which vents to atomosphere. Back to the functional side, I highly recommend staying with an option that allows you to retain the OEM plug for PCM control as it reacts quicker and to more variables than the mechanical versions.
 
  • Like
Reactions: hectwo
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top