Racing Fuel Systems

Re: Engine Masters Carb Tuning

2023-11-19T12:47:34+01:00

Don’t be scared of lean cruise AFR.
That’s what the power circuit is for. Watch your AFR gauge if you have one . I have ran a Quadrajet and a Carter 750 that would cruise at minimum 16:1 AFR and go to 18:1 with very light throttle acceleration on a 500 hp engine. More throttle brings on the power circuit and the AFR swings to rich and then richest at WOT to protect the engine.
This lean cruise slow burning mixture requires a lot of advance, up to 50-55 degrees. Usually from vacuum advance.
It only takes about 60 hp at cruise speed to push the vehicle along the highway at say 60 mph about 2500 rpm. Go too lean (cruise) and the engine will surge/trailer hitch. Pinging is usually the result of too much ignition advance and or not enough octane.
Look at your spark plugs.

Statistics: Posted by rgalajda — Sun Nov 19, 2023 12:47 pm

Re: Engine Masters Carb Tuning

2023-11-13T19:03:58+01:00

How do we know when the lean heat from increased eng. load is to high (presuming there is no noticeable detonation/pre-ignition)? Will there be evidence in the spk. plugs?

Statistics: Posted by formulajg — Mon Nov 13, 2023 7:03 pm

Re: Engine Masters Carb Tuning

2023-11-13T04:50:00+01:00

You can run lean until the engine load is high enough to create more combustion heat. It's that heat that needs more fuel to keep the temps in check. On a well tuned engine cruising above 14.7 to 1 is fine.

Statistics: Posted by jmarkaudio — Mon Nov 13, 2023 4:50 am

Re: Engine Masters Carb Tuning

2023-11-03T12:29:28+01:00

Statistics: Posted by rgalajda — Fri Nov 03, 2023 12:29 pm

Re: Engine Masters Carb Tuning

2023-10-31T06:28:13+01:00

Statistics: Posted by FC-Pilot — Tue Oct 31, 2023 6:28 am

Engine Masters Carb Tuning

2023-10-30T20:52:42+01:00

Statistics: Posted by formulajg — Mon Oct 30, 2023 8:52 pm