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u63af · Posted: Sat Feb 04, 2006 2:52 am Post subject: dump valve

If i were to block off the pop off valve and the pipe going to the inlet, would it be possible to fit a atmospheric dump valve? I know i could fit one in and get it to work but would it have any strange effects on the engine?
cheers
Sandy

Smoothie · Posted: Sat Feb 04, 2006 4:25 am Post subject:

Remember that the air you'd be dumping was already metered for determining the air:fuel mix, so if you dump it, the mix will go rich for a second or so.
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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

u63af · Posted: Sat Feb 04, 2006 5:07 am Post subject:

so i would have a puff of black smoke come out the back? Presumably when i change to EFI, it would be ok?

endwrench · Joined: 07 Dec 2002 Posts: 1631 Location: Victor, Montana

-nick · Joined: 16 Nov 2002 Posts: 2699 Location: Cambridge, MA

I think the old 962's just used an atmosphere dump/blow-off valve. However, they can shoot out ~1ft flames when they come off the throttle.

Honestly, it wouldn't hurt anything in a closed CIS system. The air/fuel would just drop down to ~5:1 or something for a couple seconds. This sort of thing doesn't make the birds and the trees happy though. Your catalytic converter and o2 sensor probably wouldn't like it much either. Might be a fun way to impress friends, or make tailgaters back off

nick

u63af · Posted: Sat Feb 04, 2006 9:00 am Post subject:

my car does not have a cat. It would be quite nice to have flames come out the back. I will maybe try it and see what happens.

bass gt · Posted: Sat Feb 04, 2006 9:42 am Post subject:

Sandy,

Let me know how you get on. I've been thinking of the same thing. Pics would be great.

Regards,

Steve

u63af · Posted: Sat Feb 04, 2006 8:50 pm Post subject:

It may be a month or so til I do it but i am keen to try it. Will let you know steve.
cheers