[Scott]

I have always been a synic about the use of dump valves and never
wanted to be associated with the RS Turbo brigade.

But recently my brother had one fitted to his Scooby, and he swears by it.

Thinking about it, it sounds a idea, Even relieves some
stress from the turbos, which has to be a good thing.

But has anyone noticed any performance difference when fitted to a GT-R?

 

[Peter]

Scott,

You've already got 2!!

Peter.

 

[Scott]

What to atmosphere rather than recirculating?

I just noticed the reverse air flow when I fitted my induction kit?

 

[x]SPHYNX[x]

Do you mean blow off valve? I would rather have a blow off valve than not have one. It is better for the turbo in the long run. You don't need one of those loud ones that all the show poneys have, just one that will do the job properly.
What the dump vavle does is release the excess boost pressure when your foot is taken off the accelerator so there is nothing flowing back into the turbo because of the closed inlet. This prevents any damage and backpressure.

 

[Peter]

What to atmosphere rather than recirculating?

I just noticed the reverse air flow when I fitted my induction kit?

Scott,

Sorry, missed this one in the plethora of posts. As I recall, dumping to atmosphere can lead to stalling without any real gains apart from even more noise.

http://www.gtr.co.uk/forum/upload/showthread.php?s=&postid=8652#post8652

Peter.

 

[DCD]

Both Shin adn Mine's have advised me not to bother with atmosphere venting BOV's.

 

[Scott]

Very interesting, Thank you both.

I have however noticed a greater pause in boost
during gear changes since fitting my M's induction kit.
It feel more than it was before.

Oh well. May be me.

Thank you once again!!!!!

 

[Paul C]

It depends on what boost your runnin, the standard 200sx recirc DV's are ok up to about 17psi if I'm correct and I presume that the Skylines have similar ones times two.

 

[hipogtr]

Paul C hit on the key point. The benefit to upgrading the BOV comes when you run regular boost at levels above which the factory BOV spring begins to leak. At this point the BOV can serve as a leak in the system.

On the GT-R, the factory BOVs are quite good and, like DCD mentioned, you'd be hard pressed to find a tuner that knows something about GT-Rs that suggests they should be replaced - even on big power GT-Rs.

Cya O!

 

[Scott]

Thanks once again gents.

Just what I needed to know.

Looks like I have saved myself a few hundred quid.

 

[Henry]

Hi Scott,
Go for the noise mate!

Henry.

 

[Jason abz]

sorry but.....

I have to agree with Henry on this one mate!!!

Sounds like a bus or truck when driving normally but when you get aggressive the sound when you change gear is simply fantastic !!
Turns heads too!!!
Don`t know of any beneifts or downfalls as i have never driven the car without it so cant give a comparison for you.

good luck whatever!!

jas

 

[Paul C]

If you don't want an RS Turbo sound from a DV go for the Jap ones e.g. Blitz, HKS, Greddy, etc. I know their more expensive, especially for you twin turbo boys but they deffo sound better!!