Need help with BOV choice

Black Majik MSP

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2003.5 Titanium Gray MSP #1699
I need help! I'm ordering the BEGI FMIC, but I want to figure out my BOV setup before I do in case I need to have a different flange welded on. I currently have the Forge BOV on the stock plastic IC pipes. It works well, but I do get stalling occasionally. Since I'll be getting hardpipes now, I thought it would be better to switch to a BOV that attaches with a flange rather than a silicone hose like the Forge does. I've done my research & the GReddy Type S seems to be the most common choice (& I can easily get that flange welded on). I saw the stickied thread, but it doesn't sound like the GReddy works perfectly unless you also run the stock BPV. I don't have any turkey with my current setup & I'd like to keep it that way. I don't necessarily need a BOV, but I just don't want any stalling once I get the BEGI.

So...what I need to know is which BOV/BPV setup you recommend for no stalling & where I should get the flange welded onto the hardpipes.
 
i am running an hks bov with no bpv and have no stalling. and i know there are a bunch of people out there that have no stalling with the greddy type s

***NOTE: the above bov's i am speaking of are being recirculated.
 
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As my set up grew I found it hard to get the greddy to both not stall and not turkey.

With my original set up (just a single hardpipe turbo>intercooler) with the greddy on there I had no problems. no turkey or stalling. I think the location has a lot to do with it. Before the intercooler the gredy is far enough back that it catches all the compressor surge but can be set tight enough to prevent dipping the RPMs or stalling.

Once I switched to a FMIC and the greddy went onto the intercooler>throttle body pipe I could set it up to either not stall or not turkey, but not do both. If I set it tight enough to not stall i would still get some compressor surge. If I set it loose enough for no compressor surge then too much air would get out and the RPMs would dip really low. It never stalled out, but came close.

Once I put the SRI on too, the compressor surge became very evident and lead to stalling from the air bouncing back up into the MAF.

I've since switched it to recirculating. I still get a nice woosh sound, but it's not even comparable to the volume of noise the greddy created when venting.

If I had a choice to create a set up, I would try putting the flange on the turbo>intercooler pipe. I know the general concensus is to put it as close to the throttle body as possible, but I also know when I had it on that pipe it worked GREAT. And our stock bypass valves were in that location. Plus it makes for very short distance for the air to travel if you decide you want to recirculate later.

I would also stick with the greddy. I've had mine for over a year with no problems. You can also find them pretty cheap on the net, the flanges are inexpensive, it's easy to vent, adjust or recirculate, and you don't need to buy extra pieces to change the sound (like the fins on the HKS) or to adjust the valve tension (like BOV that use inserted washers).
 
Get the flange welded on 12-18 inches from the TB, and run the dual setup (with stock BPV recirc). Why not run the dual setup? It's easy to find that sweet spot of no turkey and no stalling, and your Greddy is still loud as hell (believe me!). Just my .02. Our car is designed to recirc. It's not that you can't go venting only, but it will be harder because that's not how our car is designed to run.
 
but wait, you are still venting so what does it matter if you recirculate a bit, never figured that out..?
 
To get rid of the turkey you have to get rid of a lot of air when the TB closes. If you vent all that air to the atmosphere you are likely to stall because the air has been accounted for by the MAF and the ECU will think it needs to dump more fuel because there is actually less air than it has counted for. If you take a portion of that air and recirculate it and take a portion and blow it off, then you aren't getting rid of as much air that the MAF has "counted", and thus you will not get an overly rich condition and stall. It just give you more room to play with. If you could recirculate all the air of course that would be best, but you would have to recirculate a LOT of air to not get the turkey and you don't get as much of the BOV sound. Just kind of a balancing act to get the right result.
 
so leave the stock bpv in place an put the bov on the IC to TB pipe right, maybe Ill just put my forge on that pipe and try her out....
 
i have the hks ssqv as well on the dual setup. it sounds great. if you decide to go this rout, don't be suprised how expensive the flange for the hks is compared to other. its ranges from 45-65 dollars depending on steel/aluminum. just an early heads up if your tight on cash.
 
I talked to 505Zoom & I'm getting the iON FMIC with the GReddy Type S/Boostsciences Reflex combo.

Thanks to everyone for the input!
 
I running the Greddy Type-S and loving it


Btw what does it mean when you guys say 'Turkey'??
 
CometVR4 said:
I running the Greddy Type-S and loving it


Btw what does it mean when you guys say 'Turkey'??
When the TB closes and the turbo is still trying to push air there is a cavitation caused by backpressure that sounds like a turkey gobbling.
 
This thread is amusing...I went from BEGI to iON & now to Perrin. :D

Corwin: I was going to get the BEGI until I talked to Rich & realized that I didn't want a FMIC with pipes routed all over the place (plus it didn't look too great either). I told Jack that I was going to order an iON FMIC, but after reading several posts about their long waits, bad fitments, & poor service, I decided that Perrin was the only good choice. I'm glad to see that MAM is now developing a FMIC to give people a high quality alternative to the Perrin. I'm excited to see how it turns out...the design plans sound very good.
 
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i still love my turbo xs rfl....... great sound with no whistle and works great but nobody else seems to think so ... thats my suggestion
 
2 of my friends had those...it sounds great when you have a Stage III WRX pushing 21psi, but I don't think it's really suited for use on a Protege.
 
mazdaspdprotege said:
why not ?
Just what I said...our cars run lower boost than most others. That BOV is designed to make a RFL sound & you need higher boost to do that. For what it costs, it just seems wasted on our cars.
 
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