Hi Adam,
I'll take a swing at this one. First, are you using a Unisyn or some other
guage to set the idle/air draw on each carb? Couldn't tell from your post.
Also, with respect to mixture, I found that the best way to dial in the jets
is Des Hammil's method (How to Power Tune SU carbs). Pull the tops of the
carbs off, pull the pistons out, and use the tail on a set of dial calipers to
measure how far down the jet is from the top of the bridge. You do this after
the "three turns" thing. You'll be suprised how much variation there is in
the jet hight. Equalize the jet hights. Also, make sure the needles are set
at the proper hight in the pistons, or you'll wonder why the jets are
perfectly equal and the mix is still off. BTDT. It sounds time consuming but
you get fast at it pretty quick.
The last item was to buy that hideously expensive CO analyzer listed in the
various catalogs from Moss, Eastwood, etc. Expensive, but worth every penny
for peace of mind. Between the Unisyn, the CO analyzer and measuring the jet
hights, I managed to nail my carb tune perfectly. Hopefully this help you.
Good luck.
Dave Rupert
1967 TR4A
1957 TR3
1980 TR7
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