Bob,
I had the same problem with a Spit**re. After putting on a Longflow air
cleaner, an exhaust header, and recurving the distributor, I had lean top
end and rich bottome end. What I did was buy a couple of new standard
needles and started re-contouring them. I would chuck the needle in a
lathe and, using fine sandpaper, I would carefully change the taper. Mark
where it hits for idle and leave that alone but slowly add taper above
that. I did finally get it to run OK after a couple of tries but it never
was perfect. I have to admit that back then I did not understand the carb
anywhere near as well as I do (or at least think I do) now. Any way, it
only take a thousandth of an inch or two on the diameter to make quit a
difference.
I know most people recommend against this but, as you said, getting
different needles for these carbs is a royal pain in the arse. Just make
sure that the needle is spinning when you sand it so that the cross section
stays round and go slowing.
Another thing I did to get the idle leaner is I put a small tubular spacer
between the needle and the dowel pin that captures it into the brass
holder. This will move the needle down further and lean out the idle.
Then sand or file away above that point to get the rest of the mixture
right.
Good luck. This takes a lot of patience and if your friend is like me he
or she will work until it runs halfway decent and call it good enough.
With the new cam a better idle may be unobtainable in any case.
Regards,
Bill Eastman
61 MGA still missing a radiator- WAAAH
|