BOV Flutter

[FattyBoomBatty]

Ahh, make like 1.8t VW owners and reverse the bov if you can, put the outlet on the inlet flange. Why don't you run the boost controller off the boost tube near the manifold and the BOV off a manifold port like I used to? Worked fine with my RFL. Back in the day, I had the BOV t'd off the vac advance.

[Kracka]

Chris, rather than monkeying around trying to get this setup to work, why not just replace it with a BOV that won't give you any issues to start with? I'm sure the Forge unit is great and all, but it obviously just isn't working for your system. There are pleny of other BOV's on the market that will work (HKS, GReddy Type-RS, Apexi, etc.). What about swapping on an EVO IX unit and see how that holds up?

[turbotalon1g]

I think that i might be having the same issues. I currently have the yellow spring which is rated 15-23 psi, and i think basically if you don't boost within those levels then your fucked, i am gonna try shimming with the supplied shims or something.

[FattyBoomBatty]

I don't understand why it would be having any problems at all if hooked up correctly. Is there a vacuum port directly behind the throttle plate? And going on the spring capacity theory, can't you take it out, stretch it and put it back in? I did that with my RFL and it's the same as shimming it.

[A//// Guy]

My TiAL bov on my 1g would flutter with the correct spring installed too... this was with a 20G. It wont flutter if you upgrade your turbo

I would just get another bov, one that is proven not to flutter.

[Halon]

I have no problems with mine. Pretty sure I have the Yellow Spring in there, and I'm boosting around 18 on the street. Come race gas time, I'll swap in the red spring. Sorry to hear you're having problems, I absolutely love mine. I got it because all the evo guys just love them, and plus they bolt right up to the 1g flange. I'd heard their old designs had flutter, but not their new ones so much. Did you buy it brand new, or is it maybe an older one?

[scheides]

It is a brand new one, and just to re-iterate this does not happen under WOT, it happens at part throttle and it is annoying as fuck. Imagine diving into a corner. You're full throttle, bam, hit the breaks, then as you are coming through the apex at part throttle the car bucks and falls on it's face, then plants all of it's power back to the ground, and so on. As you get through the corner you pin the throttle and all is well.

Now imagine driving through traffic at 70mph. You are going to dip into the next lane, but you better be careful because there's a car creeping up and you need to get in very gently, but with just a little bit of acceleration. You ease on the throttle, move forward and start to merge. As you are about to get into position and the guy (now mostly behind you) is right on your ass, the car bucks like crazy and then everyone dies.

I'm telling you there has to be a better way! I can't believe there are so many Forge users out there and they are all either accepting of the BS or they're magically not having this problem.

I'm going to try and run the MBC from the LICP and if that doesn't work, I'm going to throw this thing into a grinder.

[Kracka]

Originally Posted by scheides

I'm going to try and run the BOV from the LICP and if that doesn't work, I'm going to throw this thing into a grinder.

I don't really see how that is going to help the problem at all. I know we had a BOV placement discussion at one point and I believe it was found best to have the BOV as close to the throttle body as possible. I know Shane added a lot to that discussion, hopefully he can add here too.

[Halon]

I have their smaller one, and I'm telling you, I don't have any issues. And as you can see, all the springs are there, except the yellow, so I know the yellow one is in there right now.

Which one do you have? I think most the evo guys buy the bigger one right? Like this?

[scheides]

Sorry, I meant I was gonna run the MBC from the LICP, not the BOV from the LICP...my bad!

ju-on, I have the top one pictured, flanged like a 1G BOV. I haven't seen the other one, maybe I'll give one of those a go.

[Halon]

I have the top one, but I'm pretty sure most of the evo guys run the lower one, which is huge, but is adjustable.

BTW, I run a forge MBC, and love it too!!

[scheides]

Here's another thing it does:

http://videos.streetfire.net/video/0...c4e7d25edc.htm

NOTE: this is not the issue I'm describing above, but it is probably the same thing

[turbotalon1g]

i emailed them about this, brandon i will give u a ride so u know what i am talking about.

[Kracka]

Running the MBC from the LICP is a great idea, I am personally a big fan of tapping the MBC into the turbo outlet or as close to that as possible.

[scheides]

I've always been a fan of running it off of the manifold, but I think in this case it might help my situation to re-route it from the LICP. Problem is, I need to tap the LICP now

[Kracka]

Originally Posted by scheides

I've always been a fan of running it off of the manifold, but I think in this case it might help my situation to re-route it from the LICP. Problem is, I need to tap the LICP now

I still really don't see this fixing your problem though.

[Halon]

I have the yellow spring, and even at 5 psi, all I get is a nice quiet solid blow off, not fluttering, no bucking. Sucks, maybe you will just have to try a different valve.

[turbotalon1g]

well i have some other possibilities for my issue yet. i will try them first.

[scheides]

Well I now have my MBC sourced from my LICP. Upper RPM flutter is almost totally gone, but the studder while at speed is still there (definitely not as harsh tho). I'm going to call forge back on monday and see if they have anything else to say. Perhaps I'll get a replacement BOV, or upgrade to another unit.

If I ditch this entirely, I'm thinking I'll try the Greddy Type RS. If all else fails, maybe I'll grab a IX/MR valve and try that. Gah, this is annoying.

[FattyBoomBatty]

Can I have your forge to experiment with?