Blow-Off Valve

[Lecher24]

Dear Nobility,

Have spent much time reading about everyone's mods and realised I should probably know a bit more about my own car!
For starters, is this BOV standard-fit for a 2006 3R? If not I have several questions...

http://www.demon-tweeks.co.uk/performance/dump-val...

TTFN,
Ian

[Zoobeef]

No its not

[F.C.]

Lecher24 said:

Dear Nobility,

Have spent much time reading about everyone's mods and realised I should probably know a bit more about my own car!
For starters, is this BOV standard-fit for a 2006 3R? If not I have several questions...

http://www.demon-tweeks.co.uk/performance/dump-val...

TTFN,
Ian

No blow off valve fitted standard.

LMFAO.

Demon tweaks description........."Extreme Performance And Sound" CHAVTASTIC!!

[Lecher24]

In that case..
Why would it have been fitted?
What would have been fitted originally?
Does it affect performance or just noise?

[F.C.]

Lecher24 said:

In that case..
Why would it have been fitted?
What would have been fitted originally?
Does it affect performance or just noise?

Noble didn't deem it necessary to fit one.
In my case I fitted a forge unit along with a hard pipe kit to my M400, it made a noticable difference in flat out higher gear changes, definately less turbo stall.
fking irritating noise though, why anyone would want to amplify this with trumpets is beyond my comprehension!

[Lecher24]

Yep, it's pretty loud. Wonder what other mods it has I didn't know about..

[JulesBliss]

I removed my Forge one as it was leaking all the time! Didnt notice a difference with or without.

[D_G]

Mine has got a HKS SSQV, definately has less lag through the gears. It's also not too loud, just a shriek to go with the air filter noise

[andygtt]

it puts your insurance up at least 30% because it adds so much power lol

[snuffy]

JulesBliss said:

I removed my Forge one as it was leaking all the time! Didnt notice a difference with or without.

If it was leaking all the time then I suspect you had the wrong spring fitted.

[Lecher24]

So it is something I can take off without any issues?

[D_G]

Yes, no worries. The dump valve helps prevent turbo stall (which can cause premature failure) but they were made without one anyway.

[andygtt]

there is a good reason they are not fitted as standard....
the turbos on a noble are way too small and boost way to low to be able to stall them significantly.. unless someone has increased boost above 3 bar it will never damage your little turbos?

of cause if you fit a massive turbo and run much higher boost then the goal posts move and you might actually need one... hence I have one but I fitted a stiff spring so it only dumps boost above .8bar hence I always have at least .8bar in the system.. it doesnt stall my huge turbo and thats more boost than a lot of people run!

the question is, how long will it take your little turbos to build back the boost into 3 meters of pipework? is it longer than the potential potential stalling of the tiny turbos?

I ran 480bhp on twin turbos without a dump valve and never had any lag on gearchange at all... it had massive lag when you wasn't on boost under full throttle as it took ages to get the turbos spinning so there was clearly no stalling at all on gearchange.

I guess you can tell Im not a fan of dump valves lol

[mgbond]

andygtt said:

there is a good reason they are not fitted as standard....
the turbos on a noble are way too small and boost way to low to be able to stall them significantly.. unless someone has increased boost above 3 bar it will never damage your little turbos?

of cause if you fit a massive turbo and run much higher boost then the goal posts move and you might actually need one... hence I have one but I fitted a stiff spring so it only dumps boost above .8bar hence I always have at least .8bar in the system.. it doesnt stall my huge turbo and thats more boost than a lot of people run!

the question is, how long will it take your little turbos to build back the boost into 3 meters of pipework? is it longer than the potential potential stalling of the tiny turbos?

I ran 480bhp on twin turbos without a dump valve and never had any lag on gearchange at all... it had massive lag when you wasn't on boost under full throttle as it took ages to get the turbos spinning so there was clearly no stalling at all on gearchange.

I guess you can tell Im not a fan of dump valves lol

Andy, is it not the fact of stalling but the fact that it puts back pressure on the turbo and just adds stress to the bearing so having the blow off valve potentially increases turbo life?

Bondy

[R0162]

interesting discussion..i had never really thought about it much...i had always had one fitted because i thought releasing the pressure allowed the turbos to spool up faster again...but it got me thinking what andy daid about having to build up pressure in 3m of pipework again, it kind of made sense.
So running without BOV can decrease lag??.....i think i am going to run without BOV for a while and give it a try..

[andygtt]

I believe the stress would be on the shaft rather than the bearings...

[mgbond]

andygtt said:

I believe the stress would be on the shaft rather than the bearings...

Ok,I don't know about these things but then if its not harming then is it onlt a good thing as it relives the strain.

I only put one on when I first brought mine because of this?

Bondy

[andygtt]

R0162 said:

So running without BOV can decrease lag??....

yes, I had one on my high boost cossie 15 years back because it was kind of considered a must back then.... then views changed and people realised you didnt need them on turbos less than a T4 so I took it off and it was faster through the gears with no other mods.

some application definatelly need one though and on a large turbo they do work... but our turbos and thus blades are tiny.

Bondy, think of it this way, its another component to fail... if it leaks then your turbo will overspool and potentially destroy itself ... i've had this happen on my cossie, but in truth any leak in intercooler, pipework etc can also cause this... but considering the dump valve is designed to leak pressure....

whatever you do, dont fit a cheap one!

[Lecher24]

[quote=andygtt]

if it leaks then your turbo will overspool and potentially destroy itself ...

OK, OK, it's going!!!

[Hollowpockets]

Andy I think your being a bit too doom and gloom here, I agree that it's less Important on our low boost cars. However when was the last time someone on here had a bov destroy a turbo or cause any damage?

There are countless people including me who use the forge one (with the right spring) and it's been faultless.

Ill be keeping mine on.

Graham