20B 3 Rotor

iTrader: (7)

Alright well I got my car up and running, and everything is behaving as it should, except for my BOV. I bought the new universal type RZ BOV from Greddy but its performing terribly, well it lets off boost but with little sound and nasty shutter.

I have tried adjusting it from all the way soft to all the way hard, and it still sounds quiet with nasty shutter.

Here is my current placement for it:



I am running the stock twins, at 10 PSI, so my question is what setting should I have it at, and how do I get rid of the shutter?. Should I just return it and get the RS because this is not working at all. Thanks guys.

KD-93R1

That location should be just fine. You said you just got the car back and running. I was wondering what you meant by that, repairs/upgrade parts/etc.. I am running Greddy RS, used to run S. Sometimes my RS will open up. What kind of boost controller do you have. Do you have a boost controller/down & midpipe/
boost guage? You may be running more boost than you think.

20B 3 Rotor

iTrader: (7)

Right now I have Greddy airinx intake, 3inch downpipe, resonated midpipe, racing beat dual tip, efini y pipe (stock bov port blocked off), greddy hardpipes. Greddy boost, oil temp, oil pressure, engine temp gauges and an AEM air/fuel gauge.

I had removed the turbos and ported/clearenced the wastegate so now I am staying at a perfrect 10-8-10 boost pattern.

KD-93R1

Did you install any new parts when you did the wastegate port job such as y-pipe &/or Greddy elbow & BOV? Also, where is the vacuum line for your boost guage connected to on the intake? What are those hoses connected to your secondary turbo air inlet pipe? Is it possible that it only sounds like the BOV is leaking and it could be somewhere else? Now I would have to question why you havent eliminated the air pump, especially since you have removed the cat-convertr. Something else I was thinking of is if you have this problem consistantly or is it more intermediant? Did you check the adjustment of the wastegate actuator rod, see Pettit Racing for tips on adjustment. Have you ever read any of Rob Robinettes tips on his 3rd Gen RX7 site? There are alot of killer tips there. Lots of good directions on things to eliminate. Oh yeah, does the car seem to fall on its face when you have the boost leak problem, because that could be vacuum related for sure. Let me know man because as I am sure you already know, you can never learn enough about these cars and there little quirks.

KD-93R1

Meant to ask you, do you not have a boost controller? With opened up exhaust and intake you should have one. You may want to look into an APEXi Power FC stand alone computer w/remote commander. You cannot go wrong with this and with the work you have done I think it is necessary. Contact Jason or Xavier at The RX7 Store for a good deal on the APEXi Power FC.

DETT

By shutter do you mean something like this http://www.youtube.com/watch?v=ChfCSfeD1Ps if so its called dose or flutter, and it is heavily debated if it is detrimental to your turbo. If you see the heavily tuned cars from japan such as skylines, supras, or rx7s they all do it. Hell my skyline GTR did it when I purchased it, that is how the previous owner had it set up with a HKS ssqv for 2 years and there is absolutely no shaft play in the stock turbos when I pulled them off.

I actually made a bet with a friend of mine when I had my evo, he bet that it wouldn't cause any effects and I said that it would destroy it, I ran with a tight bov so that it would cause it for a year running it at the strip and at SCCA events and not a thing changed with the turbo, if it would have killed my turbo I would have gotten a gt35r out of the deal, but no dice.

It sounds retarded but not really gonna hurt anything if it bugs you I would say change BOVs or contact greddy about a replacement seems the BOV is defunct,

20B 3 Rotor

iTrader: (7)

When I did the wastegate port I put on the Efini Y-pipe, as well as the greddy hard pipes and bov.

The boost gauge vacuum line is the black hose just above the blue greddy vacuum line in the first picture.

That top hose on my secondary air inlet I cant remember where it goes, but it seems pretty common.

Its definately the bov thats the problem.

Air pump will be eliminated next season possibly, havent thought too much into it.

This problem is whenever I am boosting and I let off the throttle, the bov will shutter everytime, no matter the adjustment, and its also quiet.

The wastegate is functioning perfectly.

The car doesnt fall on its face.

I will for sure check out rob robinettes page and see what I can figure out.

Nah its more like this:

http://www.youtube.com/watch?v=HEhctwQtM3s

how I want it to sound, or should sound:

http://www.youtube.com/watch?v=aB7T5vjojrs

same bov, this guy fixed the problem with his RZ, but I cant seem to figure out mine.

DETT

ya basically its the same thing in that first video as to what I posted, its flutter or dose, the only reason it sounds differently is due to a bigger turbo or more boost. Basically what is happening is the amount of boost is not opening your BOV so its recirculating back to the turbo instead of venting, the noise your hearing is the air hitting the spinning turbo wheel. You said you lowered the spring as low as it would go if that is not opening your BOV then I would check the vacuum line going to the BOV to make sure no holes (although this shouldnt be the case since you have flutter but I would still check to make sure). If there are no holes I would contact greddy, because the way the guy in the video got his working was to soften the spring completely.

ComptonAssDaniel

iTrader: (1)

Good old compressor surge.

Maybe you have a faulty BOV?

DETT

not true compressor surge, read what I posted above it is debatable but dose or turbo flutter is not detrimental to turbos from my own experience, and some of some very powerful japanese tuned cars, sounds retarded yes but highly unlikely 10psi of flutter will hurt your turbos.

This is true compressor surge http://www.youtube.com/watch?v=nCj6Spwl1CU

This is turbo flutter on the ridox supra http://www.youtube.com/watch?v=TEcN1e4WG8s

once again from my own experience and many others not detrimental and to the japs they actually believe it helps to keep spool between shifts.

20B 3 Rotor

iTrader: (7)

alright managed to fix the problem. I did the single spring mod, which left it a bit soft for the fd so I just had to adjust it a bit and now it works perfect.