Compressor Surge and Greddy BOV's

[Xeiros]

I'm going to be purchasing a Greddy BOV here shortly, and I was curious as to whether the type S or RS was better? I know the S has been discontinued from most places, but I've been able to find a few being sold on some forums and on Ebay. I did a search, but there wasn't much on this issue from what I found. One thread I saw, but it was kinda inconclusive.


Also, currently I've got a Greddy knock off on there, and I've had this flutter sound when the BOV recirculates, almost like a turkey gobble. One of the threads I came across said that thats what compressor surge sounded like. Anyone confirm this?

 

[CanadianTSi]

Your experiencing BOV flutter not compressor surge. Adjust the tension on the spring until it goes away.

 

[kmoore]

To answer question which BOV is better (Type S or RS). My experiences with the RS have been TERRIBLE! I have had two RS's not seal properly due to a bad diaphram mechanism.

 

[Gregory]

Yea, I would adjust BOV spring first... It's the advantage of having an adjustable BOV. Let us know what happens.

 

[EclipseTrbo420A]

http://www.dsmtuners.com/forums/showthread.php?p=151147002&posted=1#post151147002

Just read up there to help you

 

[Xeiros]

I tightened the nut a bit more, and I don't really hear the flutter anymore. More like the muffled pssht I'm supposed to here. And based upon that thread and the recommendations here, nobody would really recommend either one.

 

[DSMunknown]

To answer question which BOV is better (Type S or RS). My experiences with the RS have been TERRIBLE! I have had two RS's not seal properly due to a bad diaphram mechanism.

If you have a faulty/leaking/ripped diaphragm, just disassemble the BOV, take the rubber diaphragm off and apply a couple of thin coats of Permatex RTV silicone sealant. I have never tried this before, but it has worked for others with damaged diaphragms.

I tightened the nut a bit more, and I don't really hear the flutter anymore. More like the muffled pssht I'm supposed to here. And based upon that thread and the recommendations here, nobody would really recommend either one.

I really hope you didn't tighten the nut. You will strip the threading that way. You need to use the appropriate allen wrench to adjust the spring tension with the Greddy BOVs.

 

[daren_p]

I tightened the nut a bit more, and I don't really hear the flutter anymore. More like the muffled pssht I'm supposed to here. And based upon that thread and the recommendations here, nobody would really recommend either one.

Im sure you ment to say tighten the bolt but that may not be correct. More then likely it isn't surge but when are you having issues with the flutter sound? (ie at lower boost or at high boost?) If your actually surging at part throttle conditions you want to losen the bolt off. If you just getting abit of flutter at full boost you also want to losen it off abit. If its just flutter at low boost, then tighten it abit. I have the Type RS & it works great (more then I can say for most other Greddy products ) If your looking for more rice (ie louder valve) then go with the type S if you can still find it. With the larger valve in the RS it sounds more like the stock 1g valve.

 

[Xeiros]

Well, with mine, it's got the nut on the threaded bolt, and if I loosen the nut, I can turn the bolt itself with my fingers for a bit, and then have to use an allen wrench. Once thats where it needs to be, I simply tighten the nut back up just a bit, and I'm done, so in a matter of speaking, I did tighten both the nut and bolt.

 

[4G63FLA]

I tightened the nut a bit more, and I don't really hear the flutter anymore. More like the muffled pssht I'm supposed to here. And based upon that thread and the recommendations here, nobody would really recommend either one.

I have run the Greddy RS BOV all season so far and have yet to have any issues with it. I am very pleased with it's performance. So I personally would recomend the Type RS. Now my TSi is not a daily driven car, so I guess you could take that into consideration if you would like. You could ask 100 people this question and get 50 with the Type S and 50 with Type RS. Its really totally up to you on it man.

~Eddie

 

[daren_p]

Well, with mine, it's got the nut on the threaded bolt, and if I loosen the nut, I can turn the bolt itself with my fingers for a bit, and then have to use an allen wrench. Once thats where it needs to be, I simply tighten the nut back up just a bit, and I'm done, so in a matter of speaking, I did tighten both the nut and bolt.

Yes what you hav/are doing is the norm. The guy quoted said to tighten the nut insted of the adjusting bolt, think he just got his words mixed up. The bolt is used to adjust the tension on the diaphragm & the nut lock your adjustment in place. If your able to turn the bolt with your fingers, then its adjusted to the loosest setting. As a side not make sure you put some pipe dope on the adjusting bolt & inlet fittings if they don't already have it as these are common spots for boost leaks.

 

[kmoore]

If you have a faulty/leaking/ripped diaphragm, just disassemble the BOV, take the rubber diaphragm off and apply a couple of thin coats of Permatex RTV silicone sealant. I have never tried this before, but it has worked for others with damaged diaphragms.

Well, with mine the diaphram itself would not "seal" up against the bottom portion of the BOV itself. So I couldn't even do a boost leak test because all of the air that was being "pumped" into the system would go straight out of the BOV.

Got an HKS SSQV now and loven every minute of it.