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Old Nov 13, 2002 | 07:52 PM
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blowoff valve question

i was just reading in a 300zx and supra forum that there are people using two hks ssbov on their cars. how is this possible and what is the advantage of this. also would it be ideal to do this on stock rx7 turbos. thanks
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Old Nov 13, 2002 | 07:55 PM
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It's a waste of $250. You only need one BOV.
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Old Nov 13, 2002 | 07:58 PM
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I agree with Lost Time. BOV's vent pressurized air from the turbos, they've never had a problem getting it all out. No need for two.
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Old Nov 13, 2002 | 08:52 PM
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The 300zx's and supraTT's that have two BOV's have two becuase theyhave one mounted on each intake pipe coming from each turbo. They basically want to look cool, they could mount it after the IC, but I guess more is better to them.

kyle
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Old Nov 13, 2002 | 09:13 PM
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I have heard that if you have a single turbo it can be a good idea to use 2 bov's to vent the air as quickly as possible.
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Old Nov 13, 2002 | 09:39 PM
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If you have the stock turbos, getting an aftermarket BOV is a huge waste of money. The stock one works great and if you want to hear your BOV, you can just vent the stock one. Your money is better spent elsewhere (or even better put in a savings account -- what a concept!).

There are a lot of people with singles on this forum, some are even running pretty damn high boost. I haven't seen anyone running two bov's. Sounds like a worthless ricer mod to me.....
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Old Nov 13, 2002 | 10:25 PM
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Originally posted by rynberg

There are a lot of people with singles on this forum, some are even running pretty damn high boost. I haven't seen anyone running two bov's. Sounds like a worthless ricer mod to me.....
I dunno thats just what i heard.
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Old Nov 13, 2002 | 11:06 PM
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I've got a T04S running about 14-15 PSI and I just have one BOV and it works fine. I see no reason to buy another one.

Brian
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Old Nov 14, 2002 | 10:37 AM
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for a 300zx TWIN TURBo. The turbo's are on BOTH sides of the engine. It's a V6. So if you WERE to put blow off valves on, you would need two because they are on both sides of the engine and work in unison.

On our rx7 twin turbos, one would be sufficient because the turbo's are on one side of the engine, and work in a sequential setup, therefore two bov's are not NEEDED to relieve pressure from both turbos. If you only had one blow off valve on a 300zx pressure would only be released from one turbo, and not the other.
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Old Nov 14, 2002 | 10:47 AM
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we only need one becaust our turbos are the size of a ******* donut.
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Old Nov 14, 2002 | 04:53 PM
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I heard that it helps relieve the pressure. Just incase.
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Old Nov 14, 2002 | 04:54 PM
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But there is really no need for it. They went over this in a DSM forum.
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Old Nov 20, 2002 | 11:42 AM
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whatever, RX-7 still better, hehehe and I agree that the FD stock turbos are a bit SMALL! Hitachi T21's are just babyish which shows you how much power can be harnessed by the FD with larger ones in place.
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Old Nov 20, 2002 | 12:52 PM
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Wink

I've been thinking about mounting an additional one on my roof to vent air so my door will close easier.
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Old Nov 20, 2002 | 01:35 PM
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Originally posted by WONG FRIED RICE
for a 300zx TWIN TURBo. The turbo's are on BOTH sides of the engine. It's a V6. So if you WERE to put blow off valves on, you would need two because they are on both sides of the engine and work in unison.
The only time it would be beneficial or required to have two BOVs is if the car had two throttle bodies. If the car doesn't, it only needs but one. I can't remember off the top of my head if the Z has one or two TB's. If it does only have one, it only needs one BOV. Period.
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Old Nov 20, 2002 | 01:42 PM
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Some people sometimes run a 2nd BOV if they feel that their first BOV isn't sufficent for their single turbo setup. (Sorta as stated above) For instance I remember someone not trusting their Apexi BOV that came with their single turbo kit so they added a 2nd BOV which I believe was a Greddy peice. While I don't think there's an absolute need for it on a single turbo setup, I don't see any harm in it either.

As others have stated, your stock one works fine/becomes louder when you vent it and the $200.00 would be better spent on a downpipe, used catback or something else that adds performance.
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Old Nov 20, 2002 | 01:42 PM
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Originally posted by ronarndt
I've been thinking about mounting an additional one on my roof to vent air so my door will close easier.
Yeah no ****. I have run my battery down a couple of times becase of this!
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Old Nov 20, 2002 | 02:05 PM
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WOW! That must give you an additional 50 RWHP!!!
lol...:crackup :
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Old Nov 20, 2002 | 02:06 PM
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quote:
--------------------------------------------------------------------------------
Originally posted by ronarndt
I've been thinking about mounting an additional one on my roof to vent air so my door will close easier.
--------------------------------------------------------------------------------



WOW! That must give you an additional 50 RWHP!!!
lol...:crackup :
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Old Nov 20, 2002 | 02:06 PM
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I hate this computer!
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Old Dec 15, 2002 | 10:43 PM
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Originally posted by Lost Time


The only time it would be beneficial or required to have two BOVs is if the car had two throttle bodies. If the car doesn't, it only needs but one. I can't remember off the top of my head if the Z has one or two TB's. If it does only have one, it only needs one BOV. Period.
i believe the 300zx twin turbos have two throttle bodies. One for each side of the V6 engine.
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Old Dec 15, 2002 | 10:59 PM
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you want the bov mounted as close to the compressor as possible...this will reduce the amount of compressor surge that occurs....in that case...having two might be semi-beneficial...(if you simply must have two!!and you have two turbos!!)..other wise....you would have to be running two seperate compressing systems that never merge, or be out flowing just one bov, in order to see any benefits from this....
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Old Dec 15, 2002 | 11:04 PM
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hence a 300zx would use TWO blow off valves because they run TWO compressors.
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Old Dec 15, 2002 | 11:10 PM
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true...this would be slightly beneficial for the turbos to reduce surge.....as long as they are mounted close to the turbo.....
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Old Dec 16, 2002 | 03:02 AM
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You all haven't put a BOV on your A/C????? Pressure builds up in the vents and whoosh out comes my cold air.
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