haroldhettaturbo

iTrader: (2)

Hi all

My m8 is looking to get a dump valve for a bugeye.

Do they do anything else apart from the noise?

Cheers
Dave

chris25uk

nothing that the standard one doesnt do, just for the noise mate, me i love it but alot on here hate em

RB5_245

Yeah, makes it over fuel when it opens.. pop/bang and spit the odd flame if no cats... mucks the cats up overtime if you have them.

deanwoodward

ive just taken mine of much better without

haroldhettaturbo

iTrader: (2)

So apart from the sounds there is no real gain?

ALi-B

iTrader: (1)

More off a loss in some respects...From the wallet, and possible hesitation issues.

scoobykevuk

do dump valves cause turbo lag?????? subaru told my mate they do on a classic? mmm?

ALi-B

iTrader: (1)

Dumping too much air can indeed slow the turbo down more, due to the drag on the compressor blades, whilst their is little exhaust gas to drive it. So it can afttect lag.

Use the analogy of a vacuum cleaner that has a full bag...the restriction of air flow through the fan means their is less drag on it, thus the motor that drives it can spin faster.

RB5_245

you won't feel any difference at all lag wise with qa dump valve of not, unless it's an amazingly slow rubbish one. Bailey is about the worst as I know of and you wont feel any difference with that.

When porsche first fitted dump valves to there cars on the early 911 turbos it was called a noise surpressor, coz it was designed just keep the noise down. Not for performance reasons.

I've tried recirc, couple of different VTA's and none at all on my car, there is sod all difference in the real world.

[Davey]

I agree with the above, unless your running 30psi+ they are not needed.

haroldhettaturbo

iTrader: (2)

Thanks guys i will tell him not to bother.