The Ford Barn

RDVAARK · 07-29-2024, 08:54 AM

Think of the linkage as a chain of levers. The first is the pedal pad to the shaft crossing the rear of the engine. Lengthening it will slow foot travel's effect on the shaft, and slow down engine speed response-less touchy. A long set screw, or a short section of threaded rod with a connecting nut, on to the section sticking out of the floor, can do this.
Similar effect can be to lengthen the arm on the butterfly shaft. slowing its speed and allowing finer adjustment (speed governors often use this).
The object is to coordinate the position of the butterfly at cruising speed to the position of the pedal pad that is easiest to hold steady.
Explanations can be found in physics texts explaining lever systems. Another could be found in the piston vertical travel speed versus crankshaft position in an engine. Piston speed is max at 90 degrees ATDC, and 270 ATDC. Effort to tun the crank is at the minimum. Hand cranking the engine from 270 or 90 is easiest, harder from TDC or 180.
Enough confusion from me. Could someone else please elaborate to make this clear?
Russ

07-29-2024, 08:54 AM	#11
RDVAARK Member Join Date: Jul 2022 Location: Brookfield Ct. Posts: 74	Re: Touchy Accelerator Think of the linkage as a chain of levers. The first is the pedal pad to the shaft crossing the rear of the engine. Lengthening it will slow foot travel's effect on the shaft, and slow down engine speed response-less touchy. A long set screw, or a short section of threaded rod with a connecting nut, on to the section sticking out of the floor, can do this. Similar effect can be to lengthen the arm on the butterfly shaft. slowing its speed and allowing finer adjustment (speed governors often use this). The object is to coordinate the position of the butterfly at cruising speed to the position of the pedal pad that is easiest to hold steady. Explanations can be found in physics texts explaining lever systems. Another could be found in the piston vertical travel speed versus crankshaft position in an engine. Piston speed is max at 90 degrees ATDC, and 270 ATDC. Effort to tun the crank is at the minimum. Hand cranking the engine from 270 or 90 is easiest, harder from TDC or 180. Enough confusion from me. Could someone else please elaborate to make this clear? Russ