can you run 2 greddy's

regdent

Member
can i replace the stock bpv with a greddy type s as well as having one on my tb to ic pipe?? i am just starting out with the mazdaspeed, thanks for any help
 
no reason...the only reason to ever, thats right everyone else i said ever, to use 2 bovs is if you are pushing over 30psi...period end of story turkey or no turkey...a single type s will vent up to 30 psi at a t4 equivalent cfm flow rate.
 
i not long had the mazdaspeed, it has a bov on the tb to ic. but that is sucking in air and not closing properly, so i ordered a greddy and i am not getting that until monday and i need the car done asap so i am taking in to a garage who i guess will put another greddy on there. leaving me with a spare one just wondered if to sell or use it.
 
regdent said:
i not long had the mazdaspeed, it has a bov on the tb to ic. but that is sucking in air and not closing properly, so i ordered a greddy and i am not getting that until monday and i need the car done asap so i am taking in to a garage who i guess will put another greddy on there. leaving me with a spare one just wondered if to sell or use it.

how much do you want to sell it for?
 
regdent said:
can i replace the stock bpv with a greddy type s as well as having one on my tb to ic pipe??

DSMConvert said:
no reason...a single type s will vent up to 30 psi at a t4 equivalent cfm flow rate.

Technically you COULD run both. You could vent one to atmosphere and recirculate the other. It's be the same dual set up that most other are running, but cost you about $175 more (greddy rather than stock).

DSM is right though, you don't have to. The Greddy will flow much more air than the stock BPV, more than you would need to. I am currently recirculating my Greddy into my SRI and have no turkey or stalling.
 
DSMConvert said:
no reason...the only reason to ever, thats right everyone else i said ever, to use 2 bovs is if you are pushing over 30psi...period end of story turkey or no turkey...a single type s will vent up to 30 psi at a t4 equivalent cfm flow rate.

LOL!!!

Wow, you know SO much that you can say that all of us running the BOV/BPV are doing it for no reason?(jerkit) Who the hell are you to say what works for someone else? I know for a FACT that there have been at least 20 people on this board alone that have had great results from running the BOV/BPV setup, so don't go and say that the ONLY reason is if you are running 30+psi.

Quit spreading misinformation to people that haven't been here for very long... Oh wait... YOU haven't even been here that long... My mistake, you don't even know what you're talking about.
 
hehe kiddo if you think how long I've been on this site has anything to do with my knowledge go back to highschool....my statement referred exactly to his question, in no way did it have anything to do with the dual setup. To verify my statements I called directly to Greddy technical support and talked to an engineer named Mark. He verified that there is no reason to run dual greddy BOVs for boost applications under 30psi. Now to state once again there is no reason to run dual greddys. Please notice that this i just said DUAL GREDDYS, not in any way did I refer to the dual setups being run on this forums. I dont know who pissed in your cheerios this morning but get over it and make sure you read the post before raising a stink, obvisouly tx demon read it b/c he commented on exactly what i was talking abou. OH yeah and to add to my credentials I hold a degree in mechanical engineering and am ASE certified. In addition I also own my own company that designs air systems.
 
DSMConvert said:
hehe kiddo if you think how long I've been on this site has anything to do with my knowledge go back to highschool....my statement referred exactly to his question, in no way did it have anything to do with the dual setup. To verify my statements I called directly to Greddy technical support and talked to an engineer named Mark. He verified that there is no reason to run dual greddy BOVs for boost applications under 30psi. Now to state once again there is no reason to run dual greddys. Please notice that this i just said DUAL GREDDYS, not in any way did I refer to the dual setups being run on this forums. I dont know who pissed in your cheerios this morning but get over it and make sure you read the post before raising a stink, obvisouly tx demon read it b/c he commented on exactly what i was talking abou. OH yeah and to add to my credentials I hold a degree in mechanical engineering and am ASE certified. In addition I also own my own company that designs air systems.

Kiddo eh? Alright then gramps, the part of your statement that got me started was when you said "thats right everyone else i said ever". It sounded like you meant that the only reason to EVER run 2 BOV's was over 30psi. I have always respected you and your statements on this board... I don't want to start a war here, just wanted to clarify that there ARE a lot of people that are running 2 BOV's and having success UNDER 30psi. Wether or not he chooses to run 2 greddy valves or not, running 2 valves is a great idea on this car.
 
I will tell you this. There is no way to run a single greddy type-s on my car without either surge or leaking under idle. Thats why I did the 2 valve setup.
 
Hmm well I guess we both(myself included) owe eachother an apology for jumping to conclusions on the other's statements...my posts were not meant to start a war either, I was just saying that running two greddys isn't necessary. As you indicated people have had success with running both the bpv and bov together, however I haven't seen anyone yet who is running 2 bovs...perhaps we were just on different planets as to the difference between bpv and bov...when i say bov I mean a valve that vents to atmoshpere and having a valve diameter of atleast 1 inch, a bpv on the other hand is a recirc device around 3/4 of an inch in diameter. I completely agree that running a bpv with an atmosphere dump bov is a good idea when using a maf setup...
 
Notorious said:
I will tell you this. There is no way to run a single greddy type-s on my car without either surge or leaking under idle. Thats why I did the 2 valve setup.

You mean there is no way to run it VENTING on your car right?

Cause I agree with DSM, you do not need to run two greddys. One can handle recirculating all the air by itself. My car is proof of that (although I am at stock boost).

If however you want to run 1 GReddy venting so you have the nice BOV sound, then running another BOV recirculating is a good idea.

I think the reason 505 had to run two valves is because he uses the HKS SSQQ instead of the greddy type s. The HKS pulls less air all at once, so when recirculating you don't stall, but you get mad turkey. The greddy releases more air all at once which helps prevent the turkey. 505 may also be pushing higher boost levels than me so that may have something to do with it.
 
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Werd man, my bad. I knew what the thread starter was asking, but I just thought you meant ANY type of BOV because of the way it was worded in your first response. I see what you meant now, and agree that it would be pointless to run 2 Greddy valves *open vent*.

(hippy)

DSMConvert said:
Hmm well I guess we both(myself included) owe eachother an apology for jumping to conclusions on the other's statements...my posts were not meant to start a war either, I was just saying that running two greddys isn't necessary. As you indicated people have had success with running both the bpv and bov together, however I haven't seen anyone yet who is running 2 bovs...perhaps we were just on different planets as to the difference between bpv and bov...when i say bov I mean a valve that vents to atmoshpere and having a valve diameter of atleast 1 inch, a bpv on the other hand is a recirc device around 3/4 of an inch in diameter. I completely agree that running a bpv with an atmosphere dump bov is a good idea when using a maf setup...
 
just for information sake, the greddy guy lied to you, anything over 20psi on a t4 turbo or equivalent size it will leak BADLY...just to let you know :D, they also will sometimes fail early on in a lower boosted application and leak before 20psi..
 
TX Speed Demon said:
...If however you want to run 1 GReddy venting so you have the nice BOV sound, then running another BOV recirculating is a good idea.


I agree.:)

BOTH VIDS ARE LOUD

HKS SSQV recirculating by itself:

http://www.msprotege.com/members/505zoom/MOV00495.mpeg

HKS SSQV + BoostSciences REFLEX BPV:

http://www.msprotege.com/members/505zoom/Dyno run tuned.mov


TX Speed Demon said:
I think the reason 505 had to run two valves is because he uses the HKS SSQQ instead of the greddy type s. The HKS pulls less air all at once, so when recirculating you don't stall, but you get mad turkey. The greddy releases more air all at once which helps prevent the turkey. 505 may also be pushing higher boost levels than me so that may have something to do with it.

Well, if you remember way back when we were trying to figure all this out last year, Discreetspeed and I both tried a bunch of things (he was using the type-s, I was using the SSQV). We both had similar results all along the way, and both had the most success with a venting valve + a recirculating valve. So basically I just don't *think* that the SSQV is what was causing the issues... DS and his type-s were doing the same things.
 
505zoom said:
Well, if you remember way back when we were trying to figure all this out last year, Discreetspeed and I both tried a bunch of things (he was using the type-s, I was using the SSQV). We both had similar results all along the way, and both had the most success with a venting valve + a recirculating valve. So basically I just don't *think* that the SSQV is what was causing the issues... DS and his type-s were doing the same things.

I thought Discreet was runnign the Turbo XS RFL.

Even if he was running the Type S, I bet the higher boost levels (I'm only at 6psi) was the cause of the problem. I could definately see how that would overwhelm the greddy in it's current position on the intercool>throttlebody pipe. I don't get any turkey now, but I had to loosen the greddy up all the way.

I bet if I doubled my PSI to 12 I would have to relocate the greddy to the turbo>intercooler pipe (where I previously had it venting with total success) to avoid compressor surge, or go with a dual set up like you guys.
 
DS switched from the type-s to the RFL about a month or so after he put in the dual setup using the type-s and stock valve.;)
 
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