hif lean mix cruise mod
Turbo Mini Forums

hello all .
i have done a little experiment ,with the vacuum take off in front of the butterfly ,the one with the very small hole in it . i ran it round connected it to the upper side take off ,then ran a pipe from the lower side take off to a shraeder valve from a tyre ,then out to atmosphere .
the purpose of this was to create a partial vacuum in the float chamber at part throttle ,but have enough bleed off of vacuum to stop the thing going too lean to run ,then have the one way valve shut at open throttle and it all runs as normal on boost.basically replicating the metro system but with no ecu or valve .
so far it seems to work ,and gives me a lean mix thats just off misfire but only on cruise ,which is what i want.
robert.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Great idea!

Think I'll try this over the weekend!



I'm nominating Ivan for a Gold-Star for this tip!

thanks for the positive feedback lads ..

hers a few pics bit messy hope they make sense!
the original idea was to run a free flowing one way valve then a pipe to inside the car with a variable valve on it and adjust to get the right mix ,so varying the vacuum over the float bowl ... in fact ,the tyre valve ( this is necessary to stop boost blowing out of the pipe) seems to make the correct amount of restriction for MY engine and needle combo !!

this may very well be diff to any one elses. so better to use a big one way valve ,and an adjuster really , to cater for other designs .
be very carefull not to run lean at part throttle with a few pounds of boost ,that could be terminal
use a lambda preferably a wide band .you deffinately dont i repeat dont ,want to run anything other than good and rich on a a series under boost eg 12 to 1 cos their a bit fragile ...preach preach ouch splinter in my foot from this soap box ..
regards robert

Edited by robert on 6th Jul, 2006.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM