Do i need 2 BOV's

[skyline_addict]

Hey guys, i already asked this question in another thread but no answer.

I have a set of HKS SSQ BOV's and they are pooched, seals are dried up and they are leaking air = loss of boost = running rich!

I'm looking at swapping to synapse BOV's, but my question is: do i need 2 of them? I cant wrap my head around why i would need 2 blow off vavles that are connected to the same tube!

any input would be greatly appreciated

[mcfly]

no you do not.

You really don't even need one for that matter.

[J-O]

I went for the SSQV with an alu flange so..............
one is good

[skyline_addict]

!?!

no you do not.

You really don't even need one for that matter.

mcfly... please elaborate?!?!

its good to know that i dont need 2... seems strange that somebody would fork out the cash for 2 HKS BOV's when they only need 1... or none for that matter!!

Thanks gentlemen

[Skym]

I noticed Nismo didn't have any BOV's on the R35GTR endurance racecar. They just put blank plates where the BOV's were mounted -

http://jstyle2.files.wordpress.com/2008/09/nisgtr2.jpg

I've seen one big BOV (I think was Greedy / Trust) on a GTR. This was on a 640hp GTR.

It looked like the Type-R BOV -

http://www.visionr.com.au/P1010462.JPG

[NerdJuice]

**** put 4 on it. Think of how cool you'll be. The women will be lining up to bone you. And all the horse power it will add!

[skyline_addict]

hahaha thanks nerd juice... but the last thing i need is more women lining up to bone me... come on, i drive a GT-R... the line up is already so big i dont know if i'll ever get through them all... That's why i wanna get rid of at least 1 of them!!

[Wingnut]

2 are not necessary, 1 will extend the life of the turbo's, but not by a huge amount. They do help keep the turbo spooling during lift=-offs and shifts, but a good turbo will recover fast enough from a surge that it's not worth the chance of the boost leak. I did not run one the last year. And ran a single ARC the year before.

[mcfly]

2 are not necessary, 1 will extend the life of the turbo's, but not by a huge amount. They do help keep the turbo spooling during lift=-offs and shifts, but a good turbo will recover fast enough from a surge that it's not worth the chance of the boost leak. I did not run one the last year. And ran a single ARC the year before.

Even with a blow off valve the turbo still stalls once, it just doesn't repeat the process. Blow off valve or not you still have a large initial pressure spike.

[skyline_addict]

hmmm

Interesting guys, thanks agian for the input...

so you say a good turbo will recover fast enough anyways! Are you including stock turbos in the "good turbo" list? I'm new to the turbo scene so i'm a little slow :hit newb:

One more thing... i tried to look it up real quick so i dont sound too retarded, but what is a "single ARC" ??

I think i'm leaning towards a single synapse synchronic BOV, sounds convincing to me... you guys have any opinions?

http://www.youtube.com/watch?v=MU5Y6d9rh1k

[hks_gtr]

Even with a blow off valve the turbo still stalls once, it just doesn't repeat the process. Blow off valve or not you still have a large initial pressure spike.

Agree'd, I will be running no blow of valve once my engine is built, but untill then only going too be running one.

(engine being built has nothing too do with running none, just want to make it right the first time.)

[skyline_addict]

OK, so i'm getting the concept of no BOV, because no matter what the compressor wheel slows down or stops spinning... but is there something i'm missing? is it not recomended with the stock turbos or something? What is the worst case scenario for running no BOV? why do they come with them if its no big deal to run it with out?

Is there actually a benifit to running no BOV, like the turbo slowing down less or spooling back up fast because of more pressure remaining in the system?

I'm getting it slowly here boys, thanks alot!

I may be slow but i dont give up!!!

[mcfly]

OK, so i'm getting the concept of no BOV, because no matter what the compressor wheel slows down or stops spinning... but is there something i'm missing? is it not recomended with the stock turbos or something? What is the worst case scenario for running no BOV? why do they come with them if its no big deal to run it with out?

Is there actually a benifit to running no BOV, like the turbo slowing down less or spooling back up fast because of more pressure remaining in the system?

I'm getting it slowly here boys, thanks alot!

I may be slow but i dont give up!!!

you can search for a post i made a number of months back. It went into more detail about the pressures and the spikes. Benefits are cost(not a big deal), but more so ridding the system of another possible leak area. A lot of the bov's on the market will leak, and if they dont more boost will make them leak. Of course there are some exceptions to this.

If you can shift fast enough, the pressure maintained in the charge piping will be there. But it's not all that much after the first few initial spikes.


For an ordinary car running less then 2 bar it wont make much of a difference getting rid of the bov. As long as you are not running an ebay turbo the possibility of a failure is less then the possibility of blowing your rb engine up.

[skyline_addict]

;-)

sounds good, i'll search again for more info... but it's making more sense...

Cheers and thanks for the info

[Angus]

1 or 2 and the pipe?

Hey guys its a bit of an old post but i want to know if i need the pipe that throws the air that came out back into the intakes or can i get rid of it. Also what BOV would you recomend i currently have two stock R34 bov's and what do i do to convert to one? Thanks a lot.