I've been trying to get the fuel/air and timing dialed in on my
supercharged MGB. I'm getting it closer, but have some questions for
those that have more experience tuning (in both the British and
American uses of the word) performance engines.
What fuel/air ratio or %CO do you look for? And is it the same across
the range. It's my guess that I'd want to run closer to
stoichiometric at idle and at lower loads, so I can run colder plugs
without them fouling at idle, and richer at high loads/RPM (maybe
richest at peak torque/cylinder charge) to help cool things down.
The curve that I've got is that I seeem to be able to lean it out to
about 5% CO at idle, but right off of idle it goes way rich, and seems
to be running about 7% CO at load.
I've also noticed that the jet is about 1.35" below "the bridge"
to get this mixture, so I may actually want to make my needle thinner,
and less tapered at the top so that the mixture stays leaner at low
loads.
I don't suppose you have any copies of your F/A ratio or %CO on a dyno
run that I could look at?
Thanks a bunch,
Larry
--
When you discover if you're a real pacifist is on the way to the floor.
- Utah Phillips
lrc@red4est.com http://www.red4est.com/lrc
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