Mixture setting

Feb 28, 2006 4 Replies

When I blip the throttle of my 1989 Mini 998 with the original SU carb, the revs drop suddenly before idling again. Is this a sign of lean or rich mixture and what's the best way of adjusting it?



Cheers



Well get it crypton tuned for a start, or for accuracy get it set up on a rolling road?

Taffy

lean normally, make sure you have oil in the dashpot before you start playing!

if you lean it off a bit more it will stall, try pulling the choke a little and see what the difference is.

And if you go for a 'crypton' tune make sure they are well recommended as some are right monkeys!

miniman

Snip..........

Try a Colortune I've used mine on various cars since my first Mini back in the 70's.

A quick search on the net and they can be had at £21.60 from

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Anyone ever tried this?

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No, it looks interesting but I wouldn't want to be standing in front of a motor at full throttle when it lets go! I have spent a few hours playing with a mixture analyser and a long pipe up the exhaust which worked reasonably well if you had a mate to check whilst you were driving, it was a little slow on changes in mixture though!

Another method that works is welding a lambda sensor into the downpipe and using the readings from that, demon tweeks do a led display that you can use with it for muchos dosh or you can just decipher the voltage readings (between 0 and 1v normally). There is a circuit around that lets you mount a stack of ten LEDs into your dash and will give a really good indication of mixture when you are driving!

miniman

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