GFB Stealth FX BOV review
Yes, I was impressed. Its just fun, there are so many things you can adjust, its got something for everyone. I like mine quiet...er, but Skym sounds like he does want to burst pedestrians eardrums. Throw the trumpet on there and you can use your RA as a leafblower for the driveway.
leafblower sounds sweet! I can only imagine seeing a leafblower sticking outta someones hood!quick question our bpv are 100% recirc correct? no VTA at all? cuz i swear my car def blows off air, maybe just the recirc sound i hear
Yes our cars are 100% recirc. I believe the sound you are hearing is the air being recirculated back into the intake. This is why aftermarket panel filters tend to make the stock bpv a little louder as far as the whooshing is concerned.
Evolved Member
Joined: Sep 2009
Posts: 1,274
Likes: 3
From: Baltimore, MD
Hey guys,
So I recently purchased the Go Fast Bits Stealth FX blow off valve and had the chance to install it today. Installation was a cake walk, taking roughly 10 mins. If you have swapped out your BOV before you know how easy it is, take off snorkel, loosen clamps, pull and swap. Now, after installation came the adjustment process of getting the blow off valve to the right spring setting and the right ratio. This was also very easy and explained very well in the instructions included with the part. This bov is adjustable in a couple different ways, you can adjust the spring, the vacuum nipple rotates 360 degrees, and then comes adjusting the noise or how much is VTA and recirculated. I set mine at a conservative 80/20 and let the car run to make sure after revving I didnt stall or have any rough idle. No problems there and hopped in and took the car for a spin.
Right off the bat, the car held boost a LOT better, so much better in fact that I was consistently hitting high boost at relatively low rpms, and actually holding it. With the stock BPV it took a lot more weight on that pedal to get close to those numbers and not to mention much higher RPMs. Then comes the noise. Surprisingly, the GFB was pretty loud for the conservative setting I had it on. I had the trumpet accessory on at the time and decided to take it off to get an idea what it sounded like without it. The result, was not a lot quieter but enough that I wouldnt have to worry about bursting pedestrians eardrums while driving by.
Overall, I am very happy with the part, it most definitely makes a difference in performance and holds boost really well. The bov itself is solid and put together very well. Fitment is just right, its not sticking up too much and causing clearance issues. If anyone is interested I would be happy to take some short clips of what the bov sounds like from inside the car with windows up and down.
So I recently purchased the Go Fast Bits Stealth FX blow off valve and had the chance to install it today. Installation was a cake walk, taking roughly 10 mins. If you have swapped out your BOV before you know how easy it is, take off snorkel, loosen clamps, pull and swap. Now, after installation came the adjustment process of getting the blow off valve to the right spring setting and the right ratio. This was also very easy and explained very well in the instructions included with the part. This bov is adjustable in a couple different ways, you can adjust the spring, the vacuum nipple rotates 360 degrees, and then comes adjusting the noise or how much is VTA and recirculated. I set mine at a conservative 80/20 and let the car run to make sure after revving I didnt stall or have any rough idle. No problems there and hopped in and took the car for a spin.
Right off the bat, the car held boost a LOT better, so much better in fact that I was consistently hitting high boost at relatively low rpms, and actually holding it. With the stock BPV it took a lot more weight on that pedal to get close to those numbers and not to mention much higher RPMs. Then comes the noise. Surprisingly, the GFB was pretty loud for the conservative setting I had it on. I had the trumpet accessory on at the time and decided to take it off to get an idea what it sounded like without it. The result, was not a lot quieter but enough that I wouldnt have to worry about bursting pedestrians eardrums while driving by.
Overall, I am very happy with the part, it most definitely makes a difference in performance and holds boost really well. The bov itself is solid and put together very well. Fitment is just right, its not sticking up too much and causing clearance issues. If anyone is interested I would be happy to take some short clips of what the bov sounds like from inside the car with windows up and down.
It makes no sound at all when on 100% recirc with no trumpet. That being said, the diff between GFB stealth fx, and other BOVs is that you have the option to adjust the recirc level. Since most bovs vta, with us having out MAF where it is, that expected air would never show up, which would cause the car to run kinda bad to say the least. With the GFB, since its got a dual adjustable valve you can still return air back and vta just a tiny bit. So you wouldnt need a tune to run this part. You should, obviously, be cautious and not run 100%vta or anything close, but 80/20, 90/10 etc is fine imo. I would recommend this for you Slee because if its too much, just adjust it, not loud enough, adjust it. I am curious what the experts have to say about this. I know everyone says VTA is bad for a MAF car like ours, mostly because of where it is...But, with a dual port adjustable bov like GFB that can recirc and vta, whats the hurt in that if it is set conservatively?
Evolved Member
Joined: Sep 2009
Posts: 1,274
Likes: 3
From: Baltimore, MD
It makes no sound at all when on 100% recirc with no trumpet. That being said, the diff between GFB stealth fx, and other BOVs is that you have the option to adjust the recirc level. Since most bovs vta, with us having out MAF where it is, that expected air would never show up, which would cause the car to run kinda bad to say the least. With the GFB, since its got a dual adjustable valve you can still return air back and vta just a tiny bit. So you wouldnt need a tune to run this part. You should, obviously, be cautious and not run 100%vta or anything close, but 80/20, 90/10 etc is fine imo. I would recommend this for you Slee because if its too much, just adjust it, not loud enough, adjust it. I am curious what the experts have to say about this. I know everyone says VTA is bad for a MAF car like ours, mostly because of where it is...But, with a dual port adjustable bov like GFB that can recirc and vta, whats the hurt in that if it is set conservatively?
Not being negative or anything or knocking on this BOV and it may be good and cool and all but I have seen how much these things are because of where they are made. For the price I would MUCH MUCH rather have a Synapse. How many Psi is the GFB good to or what is the max boost it can hold?? I know the Synapse is tested to 100psi right? So the synapse is cheaper and easier to use at least that what it sounds like. So another question I should consider could be are there no other kits avilable or something like that so up to you just my
.02 that is all.
.02 that is all.
Evolving Member
Joined: Jun 2010
Posts: 338
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From: Winnipeg, Canada
some people say that a fully recirculated bpv/bov helps keep the turbo spooled during gear changes, but that's yet to be proven.
Evolved Member
Joined: Sep 2009
Posts: 1,274
Likes: 3
From: Baltimore, MD
it's just for sound really. 100% recirculating would offer just as good performance as VTA, but upgrading from the stock plastic one is a must, imo.
some people say that a fully recirculated bpv/bov helps keep the turbo spooled during gear changes, but that's yet to be proven.
some people say that a fully recirculated bpv/bov helps keep the turbo spooled during gear changes, but that's yet to be proven.
Evolving Member
Joined: Jun 2010
Posts: 338
Likes: 0
From: Winnipeg, Canada
it's a must if you're concerned at all with performance. it's like driving with a loose coupler, imo. it's leaking pressure which in turn the turbo has to work harder to spool to open the wastegate. Mitsubishi finds it's an acceptable amount of loss, but you'll definitely notice a change in engine response when you do this upgrade.
Evolved Member
Joined: Sep 2009
Posts: 1,274
Likes: 3
From: Baltimore, MD
bpv = bypass valve - usually refers to full recirculating unit.
it's a must if you're concerned at all with performance. it's like driving with a loose coupler, imo. it's leaking pressure which in turn the turbo has to work harder to spool to open the wastegate. Mitsubishi finds it's an acceptable amount of loss, but you'll definitely notice a change in engine response when you do this upgrade.
it's a must if you're concerned at all with performance. it's like driving with a loose coupler, imo. it's leaking pressure which in turn the turbo has to work harder to spool to open the wastegate. Mitsubishi finds it's an acceptable amount of loss, but you'll definitely notice a change in engine response when you do this upgrade.
Like I said, you will notice a difference in how well the bov holds boost. It works excellent and is definitely something I would recommend to someone who is concerned with the stock bpv. Just something I wanted to add in, because it seems like there is a big misconception about this. The amount of spring tension has absolutely nothing to do with the amount of boost the GFB can handle. No matter what boost pressure your turbo is putting out, the valve will not open until the gas is let off.
also bov is not just for sound, it is to help with compressor surge that would otherwise damage the turbo from so much back pressure when you let off the gas. if your pushing alot of boost how much can really be recirculated back thru those lines. im no mechanic and im still new to the whole turbo thing but from what i understand maybe it is better to VTA some in a more conservative manor then to vent it all or recirc it all. Plus who wants to replace a turbo, not me!
If you are venting a small amount, it should be fine. But, the GFB stealth fx, as I said before, has a setting for adjusting the spring tension. So, if you are running it full recirc and experience compressor surge, you can loosen the spring up a little until it goes away. Again, this and the other features of this bov is what sold me on it. I researched a lot of other bov manufacturers and I found that GFB catered most to what I was looking for. EvoTsi seems to prefer Synapse bov. There design is a little bulky and just plain ugly in my opinion and it is not nearly as versatile and i really doubt I or anyone else on this forum will ever be running anything close to 100psi, so it seems like more of a gimmick then a selling point. I wish I could show the quality of the GFB piece. Just looking at it, holding it in my hand, you can see and feel the quality. They're QC is top notch and I am yet to hear any bad reviews about their product. If all the things I described in my review, matched with the quality of materials and engineering that goes into GFB bovs is more a concern to you than price, than there really isnt much else to say. Anyone can say, "oh this bov is better because." Its better because you deem it better for your needs, I am just trying to provide a solid review for RA owners that were considering GFB and just didnt have a solid review to help them decide.