4 replies to this topic

[Purple Tom]

Hey

I've been away from mini's since october, apart from taking them to pieces, so I'm struggling to remember some things!

Which way do you turn the mixture adjuster screw on a HIF44 to weaken the mixture? Is it in to weaken, or out? I can't remember!!

Also, i seem to be getting pretty poor fuel consumption from the Cooper at the mo, it has basically a stage one kit fitted to an MG Metro engine, with a BDL needle. The timing is right, but I haven't got winsu so I can't check if the needle is right. It runs much better in mid range now than it did with the old BFY needle in. It appears to have used about £28 worth of Optimax in the last 150 miles, which as a rough guesstimate works out at about 25 mpg.

The exhaust is black, so I think it may be running rich, but will weakening the mixture slightly affect performance or is it just a case of turning the screw a quarter of a turn at a time until there's a nice balance between performance and fuel consumption??

Thanks!!

Tom

[Bungle]

with my 1990 cooper i always find i do less MPG on optimax

[Alexcooper]

all i know is that there is defintly a balance between the 2 if you dont give it enough it will couch and reject it but if you give it to much it does the same a small tweak could make al the differance as minmaddarren would know, but he thiks his needle is going too. But "have a Play" thats what my dad always says lol

[Guess-Works.com]

Quick tuning guide....

Looking from the side of the HIF, clockwise rotation with rich the mixture, counter-clockwise, weaken,

Get your motor running warm at about 1200 rpm, vac removed if you have a vac dizzy. weaken the mixture until the rpm drops, then richen until steady again, this will be an ok setting, but any more accuracy than that will require a glass spark plug.

You BDL needle is one of the standards for an MG Metro, so is a good starting point.

[Purple Tom]

ahhh right. :nugget: i just turned it clockwise to weaken before leaving work, silly plonker.

right, well the engines coming out tomorrow to have a new 'box so i'll have a tune up of it once its back in the evening.

I've got access to a colourtune (hopefully!) so should be able to get it fairly close with that!! Thanks guessworks!!

Tom