... wow, frustrated.

i am hearing everything from... "this is normal...." to " this is very bad (hard) on the turbo and it should not be doing this.

not sure if i should be persuing this further or not...

any tuners care to weigh in on this?

 

It is normal. The MR is a strong BOV. There are some cars that dont even have a BOV and their turbos last forever. As warrtalon stated it happens, even on a stock car you just can hear it becuase of the stock intake and box. Shift faster, let out of the throttle quicker, or put the stock intake back on and you wont hear it. Most aftermarket BOV's will make the flutter worse at part throttle so people have some they like, search. Ours cars build alot of boost quick and so low in the RPM's it is very hard to get good release at low and high loads. Flutter at low RPM's low load and hold great boost up top. No flutter and leaky at high boost. Its hard to find a medium.

 

agree on normal

I have a bone stock IX MR and it's exactly as Warrtalon states ... if you let off the gas lightly and not quickly, there is some surging ... I quickly learned not to do this

You can go partial throttle, but when you lift, lift quickly and completely to allow the BOV to fully purge in a single breath ... makes things much smoother.

 

Your car, if all stock, should have absolutely no surging or stuttering. Even an intake and exhaust should not cause it. I have had this issue on my car, tried 4 different BOV's (stock, Greddy, Forge, Tial) and the only one that did not stutter at all was the stock BOV. Never ever stuttered.

EVOlutionary

 

This is not true. He doesn't have the same stock BOV as you. His is a much stronger metal bov (e.g. JDM MR DV). Intake and exhaust have nothing to do with it other than the intake allows him to hear the "flutter." I have yet to ever hear any flutter, but I know when my car experiences compressor surge. It's one of the drawbacks of having a strong BOV that doesn't leak boost.

 

By "if all stock" I meant if the BOV was stock also. I find it hard to believe Mitsu would sell a car that has compressor surge straight from the factory. I could be wrong, though. If I am wrong, he could try the plastic '03-'04 BOV if he really want to get rid of it. Maybe that will help. Good luck! I know it is a pain in the a$$.

EVOlutionary

 

Er, yes, I know we are talking about the stock BOV. I was telling you that what you experience with the weak, crappy, plastic BOV is nothing like the JDM MR DV. It's a much stronger unit that holds boost far better than the plastic one. It's not that Mitsu sold the car with compressor surge - the compressor surge is caused by improper driving: part-throttle, slow lifting in high gear after buildiing low boost. If he goes back to the plastic BOV, then he may completely get rid of any surging, but that just means he's happy with boost leaking out and sub-optimum performance. It's a balancing act between holding boost to the extreme and bad compressor surge. The MR DV _can_ cause surge if driven improperly, but once you recognize what causes it, it's easy to change your driving habits (in top gear). Then, you end up with no surge and a BOV that holds all the boost rock solid.

 

Hey, man

I have a IX and had the same problem as you do. I have an intake w/ the injen hard pipe kit. I switched the BOV to the proper OEM position and the flutter was gone. It is perfectly..and I mean perfectly smooth transition at part throttle and low to 0 boost to vacuum.

PM me if you need more info.

 

Good advice the Forge RS is on amazing peice of work and it can be adjusted to totally smooth out and eliminate any flutter what so ever

I sell them at a very dicsounted rate - PM for details

 

The stock MR BOV that comes with the Evo IX is on the stiff side and it can create fluttering

When the car is 100% stock you will not notice this at all

However - when you modify the exhuast - e.g. modified down pipe and free up back pressure then the tendancy increases to flutter on partial throttle

This is why a fully adjustable bov like the Forge RS will allow you to dial in the BOV to suit your own individual driving style and prefered "feel"

 

You keep referring to the "JDM" MR DV, that is why I brought up the stock issue. If the '06 BOV is the same as the "JDM" MR DV, then quit calling it "JDM". It is now USDM. I think that will help keep things more simple and easy to follow.

As for compressor surge being caused by improper driving - you can feel free to change your driving style to work around a problem your car is having. I personally would rather fix the problem than just tip-toe around it. Having to drive my car like a light switch , on and off, is fine for drag racing, but unacceptable for any other kind of driving. It is absolutely necessary to be able to drive at part throttle and be able to lift off to slow down smoothly for a sweeping corner while not upsetting the balance of the car.

EVOlutionary

 

Excatlly . If you put an intake on a turbo car you hear flutter at partial trottle. When im gasing it I let of all the way and let the blow off valve do its job then I resume gas at speed I want.

 

This flutter could also be turbo compressor surge noise which is also normal with an aftermarket intake