Ok so for the time being I am running a very small weber carb on my Fiat. Back when I first bought the car I scored a NOS Weber 30icf (the factory carb) for under $5
Just like this one.
Over time I "upgraded" to the 2 barrel Weber 30DIC and went with a 286 cam and higher compression but I could never get the idle circuit to work properly (questionable old carb rebuilt by myself with a 30 year old OE weber kit.) and after a while got sick of the crappy cold starts and constant massaging of the throttle to keep it idling so I bolted on the old single barrel. RESULT!!!! instant awesome idle, choke works great, absurd fuel economy (like 55mpg) and low end performance was rather improved but of course the top end where it used to pull hard to 7500rpm it now starts to peter out at 4500.
Anyway back to the point. I had a few minutes to spare so I swapped out the main jet from a 1.15 to a 1.25 to see if top end would improve, and it did by quite a large margin. It pulls pretty good until 6800rpm. The problem is that now the choke doesnt work any more and there is a large bog from 2000 to 3500RPM.
Should I have stepped down on the air corrector instead? Should I have changed them both? What is the correlation between the two? This carburettor black magic thing is confusing to a simple Megasquirt based caveman like myself.
MS is on the way. Just need a few more bits to finish it up.
