Hi, I'm working on this 48 Lincoln Continental convertible V12 and she won't rev over about 2,800 rpm once warmed up. Runs great at idle, even though it's having high rpm problems. Sometimes when the
engine is cold it will rev up just fine until it is warmed up or by the time i pull out of the driveway. The problem is present with or without a load. Can drive around but won't go over 40 mph once warmed up.
I've rebuilt 2 different carbs, It as an electric fuel pump pushing from the tank and has 5 psi at the carb. Gasoline is fresh.
New points, condensers, ballast resistors, spark plugs, spark plug wires, fuel filter. I made my own coil plate to accept 2 universal 6 volt coils. I've tried old points and old condensers before the distributor was sent out for overhaul and points setup. I've tried bypassing the ballast resistors. Spark plugs are gapped at 28 thou and are a nice tan color. Nice blue spark will jump a 1/4" gap.
Vacuum advance is working according to a mark I made on the crank pulley and using a timing light while revving the motor. I've pulled the timing cover off to make sure the marks were lined up. At full throttle, vacuum gauge with exhaust disconnected shows 5" and at idle the gauge bounces slowly from 15.5"- 16.5" (this variation could be from points slightly out of sync, but problem still existed when points were in sync). Brand new optima 6v battery. Can't find a vacuum leak. No valve ticking. No smoke, no oil burning. All cylinders have 100-110 psi. Hope someone can help.