Specs: 74 scamp 440. Stock bore, stock pistons, stock bottom end.

Comp 274 XE hydraulic cam with 1.6 roller rockers,

cam spec 230° / 236° at .050 Lobe Separation: 110 Intake Centerline: 106° installed advanced 2 degrees for piston to valve clearance. Lift with 1.6 roller rockers .520 in/.523 ex

452 heads cut about .100 to make them closed chambered. Home ported with templates.
Schumacher headers with full exhaust.
M-1 intake with Speed Demon 850 DP carb.
Automatic with 3:55 gears. 32-3500 stall that is fairly loose.

I'm using a Mallory 685 ignition box with a unilight dist with the timing advance locked out. I can pull 14" of vacuum at idle, but dropped it down to a steady 13. The box has a 10 deg start retard.
Total timing is about 34-36 even at idle... It will ping just a little under a heavy load, like when the tires bite hard.

I am using an innovative A/F gauge with the heated sensor in the Right bank collector
I can get the idle lean with the idle slots in the front and rear where they should be. The idle speed screws are only about 1/2 turn from not touching the lever, front and back. The four corner idle mixture screws are all responsive and all out about 1/2-5/8 a turn. It will idle nice at 14-14.5 AFR. Setting still I can rev it slowly and it stays in the high 13s and low 14s. When I put it in gear it is in the 11-13 range cursing around and at a steady speed or 40-50 mph. I don't know for sure if anything has been done to this carb.

I know the timing seems weird... where do I start?