440 still idles with screws turned in

[RJRENTON]

8.5 psi is NOT too much when the manufacturer recommends it, which Carter did.
My Motors Manual covers 1959 to 1966 year models. The quoted specs come from the car manufacturers.
The quoted pressure for the 426 Ramcharger is 6-8 psi & the same for the Hemi.
Some 273 engines are listed at 6- 7.5 psi.
If the FP is changed from the recommended FP, the float level should be adjusted [ for any carb ]. Carter provides a chart for that & guess what? It goes up to 10 psi.

IMO.....the authoritative source for the engine and fuel system specs, including carb float levels and float drop settings, fuel metering components and fuel pressure and volume delivery requirements is the Factory Service Manuals (FSM). MOTOR'S MANUALS and CHILTONS MANUALS are best used as door stops....they're too general and too vague and most of the time inaccurate. If you want accurate information, specifics and terminology refer to the FSM specific to your vehicle. Just my opinion of course.
BOB RENTON

 

[Geoff 2]

The info in Motors Manual does come from the manufacturer.
Do not about Chiltons.