Your cable may actually need to be longer than a stock 383 dart. The Performer RPM is significantly taller than stock iron. Also you never said whether you have a B or RB engine. 440 is taller than 383.
Do you have the mopar linkage adapter on the 850 holley? Something is weird here. If the cable housing is attached to the firewall and adjusted properly at the bracket ( you do have the correct bracket?) then it should work.
It's a 400 block and I do have the adapter.and a Mancini high rise bracket. As I mentioned, using the 71 Charger cable, when attached to the carb., and clamped down in the bracket it runs to the firewall and looks like I believe it should (not too short, not too long). But, when I got under the dash to connect it to the pedal, the actual inner cable sticks out about 2" past the little hole it goes through in the pedal arm (with the pedal in the full up position).
