I am buying some Buschur upper IC pipes and it comes with a flange and a 1g BOV already on it. I saw that most-wanted used this setup and was wondering if it is that much better than the Evo 9 BOV. I searched but couldnt find too many relevant threads about this.

 

Stock IX DV, which is the JDM MR DV. It's an improved version of the old 1G BOV. Buschur used that as the BOV of choice when VIIIs came out, because the VIIIs had plastic BOVs. We didn't get the aluminum JDM MR DV until the IXs were released, but BR's packages were already set.

You would be downgrading if you went with the 1G.

 

AS far as i,m concerned the 1G is one of the best Bov,s out there for nice smooth driveability,and it will hold at least from i,m told 26 or more (crushed). Thats the valve i used on my 03 8 with the BR uicp, and its what i,m using now on my BR350IX (005). I,ve tried 5 different bov,s between both evo,s and this one is the best. I an not putting down the stock IX valve as they act pretty much the same. Great driveability and can hold boost.Either one you cant go wrong with

 

The 1G holds 16psi uncrushed and around 21psi (efficiently) crushed. It is not as good as the JDM MR DV/IX DV.

 

The stock Evo 9 already comes with a good diverter valve and than you switched it to an inferior one? Why?

 

I'm running an uncrushed 1G right now and it is holding 21 psi (about 1.5 psi boost taper from peak to 7500 rpm).

 

Vigo, the BR330/350s come that way.

Rich, that doesn't matter. The turbo will compensate for any leaking of the BOV by working harder than 21psi to maintain what you see on the gauge. Taper is not a function of the BOV. It's just like with the stock plastic BOV, except worse. We run 19-20psi in stock form even with that BOV despite the fact it opens at 13psi if you pressure test it. That's why I use the word "efficiently." You can run 24-25psi on the stock plastic BOV just fine, which is what I did when I ran 12.22 with a cat-back, but that doesn't mean the stock plastic BOV was holding that boost efficiently.

 

Regarding the Buschur UICP with the 1G BOV that is what I actually have on my Evo 8 MR. It holds the boost fine but mine is crushed.

I also have a non crushed 1G BOV that I bought for my GSX. I am unaware of the holding psi of a stock 1g BOV but I can tell you that the stock Evo 9 BOV leaks at around 26psi (I have done the test and I had recorded the boost).

Either way both BOV are excellent in quality.

Carlos

 

I recently put the 1G back on after having a tightly sprung Forge valve for the past couple of years (which has a lot more drivability issues). I didn't have to increase the duty cycle on the EBC to maintain the same boost level, so I'm not sure how the turbo could be working any harder?

 

The BOV leaks out some of the pressure beyond the point at which it is efficient, so in order to maintain the boost you are demanding, the turbo spins faster. That's how boost leaks always work. You have a leak that you can't see, hear, smell, or touch without doing a pressure test, and the whole time the turbo is working harder to maintain the boost you are telling it to run. It compensates for any leaks by working harder at the source to maintain what you see on your gauge.

 

Thanks for the correction.

 

I guess I'm just not following. If you have closed loop boost control or a ball/spring MBC, then I would agree with you. But with an EBC that isn't running in closed loop, then there is no target boost level associated with the duty cycle. If you have a leak, then boost will be lower. If it's cold out, boost will be higher, etc.

 

Rich, you are running the Dejon tool 1st Gen right?


I am running that on my Buschur setup and its perfect. It held to 25 psi on the boost leak test I did. Pog0, go to http://evo.dejonpowerhouse.com/ and check it out. 10 dollar fix for a perfect BOV.

 

Dunno, Rich. Maybe yours is magical?

Testudo, using the Dejon fix is completely different than just running a regular 1G. If that's what Rich has, then he was witholding that information, so I doubt he has it.

 

MY BR350 came with the flanged uicp with a forge DV,(the one with the 4 springs). The driveability with every spring i tried was terrible.As i used a crushed 1G on my 03 and like it so much i had Dave Buschur overnight me one after i called him from Medina Mitsubishi and told him about the terrble driveability of the car after my test drive. The next day i got it,crushed it and the car has been outstanding since then. I have 9k on it now and loving it more everytime i drive it. So to really answer your question i never had the stock IX bov on the car because it would not mount to the uicp.