dump valve & boost gauge
Turbo Mini Forums

hello
just fitted a take off to the inlet manifold for the boost gauge and dump valve, spoke to nick (bud 666) and fitted as he described, when I started it up the gauge is erratic and goes down when reved, I know it does not go up unless under boost and also cannot hear the dump valve, does this also not work unless under boost.
would of phoned nick but don't want to keep bothering him on a weekend,
how do u stop the gauge being erratic
thanks

the dump valve will oly make a noise when there is boost pressure, the small pipe from it conects to the inlet manifold so when the throttle shuts it is sucked open and will vent any boost pressure.

And you won't get any boost when just revving, you need to drive the car.

Sound to be working as expected to me

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

thanks lads put my mind at rest

is it not possible to rev an engine into boost then?, only under load?. I have a similar symptom with mine, tried to rev it up to hear the blow off valve but cant hear much.

133.5 bhp 123 lb torque 116mph @6640rpm 9.5psi
Shakespear RWYB 14.995 91.83mph

about the erratic boost gauge how can I stop this or is this how it is thought I might be able to get a smooth reading

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

give us a ring or something tomorrow if you want dude, can call round on the way back from curborough.

i put a restrictor in the vac pipe to the boost gauge and it made it nice and steady. If its pissing you off it might be worth considering.

what do u mean a restricter

been trying to find a link on the web, but there are no pics. My gauge was supplied with a t piece and one of the legs had a little brass insert in it to restrict the flow of air. This smoothed the gauge out.

There's tons on google about it, but nothing really useful.

If you are running soft silicone vac pipe it might be worth putting a small cable tie round it and tighening a bit to see if that helps.

cheers mate will try that

What diameter was that Ric? Noticed my gauge was a bit flappy on idle.

can't remember to be honest, was ages since i fitted it. I think the OD was about 3-4mm and the brass insert took it down to about 1mm. I can take it off at the weekend and take a pic if that helps. :)

Ah cheers don't worry though mate now I've got a rough idea I'll have an experiment and see what works.

Mine is erratic on idle. Off boost just shows vacuum when throttle off (normal) and is smooth when cruising and then smooth on boost. Bounces only a little, and doesnt bother me on idle... sounds normal to me too.

Pete

1132cc Turbo ~120 bananas ATW - Fun Fun Fun