Holley Carb Tuning with AEM A/F gauge
Well, I got tired of getting 10 mpg with my Blueprint Engines 306 in my 65 Merc Cyclone. I just received a AEM A/F gauge kit from Summit Racing. A exhaust shop welded a bung to the exhaust pipe on Friday. I'll be installing the parts today.
It seems there are three areas to focus on, idle/transition, cruise and wide open throttle. The engine has stock exhaust manifolds on it now so it's chocked a little bit. On a side note, I install a K&N Substack a week ago. It must help airflow because I noticed a distinct off idle stumble with it on the engine.
Here are the baseline of all current settings car, engine, carb and tuning. I'll try to make one change at a time.
3.50 gears with trutrac in the rear end. P215/70R15 tires. Toploader trans, not close ratio.
Vacuum at idle (900) 15 inches, 20 inches at 2000 rpm (40 mph), 22 inches at 2500 rpms (55 mph), 20 at 3000 rpms (60 mph), 18 inches at 32-3300 rpms (65 mph)
Timing is set at 16 at idle, lightest springs installed in dist so it's all in at 2500 rpms. MSD distributor 8582. Plugs are Champion C61YC gap is .044. Wires are Moroso 8.8 ultra 40.
idle screws set at 7/8 turn out. Main jets are demon 66, PV is 6.5, nozzle is a 33, has a blue cam in it (not sure which position).
I'd appreciate any suggestions on which circuit to work on first or recommendations.