Author Topic: Dump valve set-ups  (Read 3527 times)

Offline Max

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Dump valve set-ups
« on: August 24, 2008, 11:26:20 pm »
Hi chaps,

Getting round to putting a dump valve on mine, just wondering what set-ups people are using and what ones to go for.
Currently running no dump valve and I wish to keep that sort of noise, nothing too Cosworth-esque lol.
Im guessing I just need a silicone t-piece in between the throttle body and bendy plastic boost pipe,  and just run it off there.
What does the small bit of hose coming off the dump valves do and is it needed?

Cheers.

 :D

Offline Alexiskayak_7

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Re: Dump valve set-ups
« Reply #1 on: August 25, 2008, 12:26:33 pm »
[quote pid=3540 author=Max date=1219616780]Hi chaps,

Getting round to putting a dump valve on mine, just wondering what set-ups people are using and what ones to go for.
Currently running no dump valve and I wish to keep that sort of noise, nothing too Cosworth-esque lol.
Im guessing I just need a silicone t-piece in between the throttle body and bendy plastic boost pipe,  and just run it off there.
What does the small bit of hose coming off the dump valves do and is it needed?

Cheers.

 :D[/quote]
You mean where you connect the little hose that comes out from the BOV? You connect it, by using a t piece in the fuel pressure regulator little (vacum/pressure) hose
« Last Edit: August 25, 2008, 12:26:56 pm by Alexiskayak_7 »

Offline Raw

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Re: Re: Dump valve set-ups
« Reply #2 on: August 26, 2008, 01:04:25 pm »
[quote pid=3540 author=Max date=1219616780]Hi chaps,
Currently running no dump valve and I wish to keep that sort of noise, nothing too Cosworth-esque lol.
 :D[/quote]

Try a recirculating valve like this or get one off a standard turbo car at the scrappers. Somebody on here could suggest a suitable donor.

Offline breadman

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Re: Re: Re: Dump valve set-ups
« Reply #3 on: September 01, 2008, 08:27:16 pm »
From what I have read, O.E. recirc valves tend to be pretty poor. Get one from a breakers off a car with some mileage under its belt and it'll more than likely be next to knackered.
Apparently, the Forge Motorsport ones are very good indeed (as with just about everything they manufacture).
I'd really prefer the recirc. type BOV on mine eventually. However, its not that easy to (neatly) route the pipework back to the turbo inlet. Possible, just not easy. So much gubbins, so little room!

Offline Andy

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Re: Re: Re: Re: Dump valve set-ups
« Reply #4 on: September 05, 2008, 04:55:25 pm »
OEM dump valves are absolutely fine, you're just better off buying a new one suited to your application rather than a random knackered one - especially as they're fairly cheap. They only have a bad reputation because so many modifiers buy tired secondhand OEM ones designed for 7psi of boost, and expect it them to last 10,000 miles of 21psi abuse. Nothing wrong with Forge valves either, but why pay silly prices for new shiny bits when more thoroughly tested designs can be had cheaper. The Bosch valve on my Saab is the original one, and although it works still it's a little tired now - but then it's done 180,000 miles so I'm not surprised!

The pipework's not an issue to sort out at all. My first attempt was reasonable, but I re-did it all when I switched to a GT throttle body and Emerald. Am now using an off-the-shelf t-piece and a scrapyard boost hose so I've got a recirc installed very neatly and out the way very close to the compressor.