Blow through charger part throttle issues
Turbo Mini Forums

Hi all. Im doing a blow through charger and having issues with it on part throttle. Its got standard rockers fitted now rather than the 1:5's it did have and a 286 cam i think off the top of my head. Also fitted is the bini bypass valve. It idles fine but if you try and drive it on part throttle the valve takes too long to close. We have also fitted a dump valve to help and it has but its still not right. Its running at 1.2bar at the mo. Maybe a weaker spring? Another bypass valve? Can anyone advise? Many thanks guys

feature=mhum

Might help if you gave more details on the setup, and the actual problem.

What issue do you think this bypass valve is causing ? You dont explain any actual problems.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

well. The valve sits between the ic and the plenum. When you take your foot off the pedal, the valve is sticking. You can clear it by bliping the throttle and from full throttle to coming off it works fine. Its at part throttle/cruise where the problem is mainly

feature=mhum

sticking open ? sticking closed ? what opens and closes it ? what sort of design is it ?

Mechanically, with no input from the engine does it open or close itself ? Is there a spring of any kind ?

Again, be specific.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Further confusion too.

Nice pictures of the build in that photobucket. But that is a suck through system in the photos ?

Any actual details on this bypass valve ?

And surely if you fit any item that dumps air externally at any time....it will be chucking air and fuel out from the carb ?

or are the pictures not showing the current system ?

Edited by stevieturbo on 10th Jul, 2010.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

No those pics are of the old vmax setup. The valve is the one used on the bini and closes when the throttle is applied and opens to vent the boost out when off throttle. It is mechanical and acts much the same as a dump valve. It has a butterfly and vacum pipe and sits inline just before the plenum. Its trying to stay close when you come off the throttle and you have to blip it to get it to open proper

feature=mhum

All sorted now. Next stop MOT!

feature=mhum

what was the issue Jonny? Sticking valve?

Mr. Prawn, the friendly Crustacean- slowly making steps towards forced induction.

not to sure. We have relocated it and seems to have cured it!? Taking it for its MOT tomorrow and hope to have it home on the weekend!

feature=mhum