I have a 998 that is supposed to have a stock head, sports cam and rebuilt carby. It is currently running very rich and flooding when starting. I know I can change the mixture setting using the mixture screw but I presume that only changes the idle mixture. How do I change the mixture at all revs?

I'm not sure what carby it has, I measured it where it goes into the air cleaner and it seems to be about 1.75 inches across. I will post images as soon as I figure out how!

Also, when it does flood and I remove the spark plugs they are all very black but no. 3 seems to be more flooded than the rest. Is this normal?

Photos below:

Hi jme.

Your car has a 1 1/4 SU fitted. It sounds like it has the wrong needle fitted, you need to take the top of the carburettor & remove the needle from the piston to see what type of needle is fitted. It would have a "GX " needle fitted as std, but as the manifold you have fitted is a std manifold cut off the exhaust, a richer needle is often fitted to get over the "flat spot" you get with cut off manifolds, eg a "M" or a "AN" Check it and see

It also looks like the float bowl is fitted incorrectly, on the wrong angle. The float bowl need to be vertical. This could be causing flooding problems.

Regards
David.

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