Bought a 83 diplomat. Someone deleted the lean burn and used a points dist.car runs like it's only hitting on 2 cylinders at idle but seems to smooth out under acceleration. I wired a electronic dist up and still get the same thing.new plugs,wires, cap and rotor,timing set @ 7 btdc. I thought maybe the 2bl carb was bad and installed a 4bl intake and carb and have the same issue. I'm way over it and hopefully someone can school me on this.lol

Needs more advance at idle.

It pings and knocks if I advance the timing anymore..

I think stumpy is saying you need more initial timing. Not more total timing. But I don't want to speak for him. I may be wrong.

Are you setting base timing with vacuum advance hooked up? And at what RPM are you at idle?

I'm setting base timing without the vacume advance hooked up and I'm @ 800 rpm @ idle

How steady is the timing mark? Wondering if your timing is wandering due to worn timing chain.

I'd set the initial at least at 15 & maybe 20 then shorten the slots with the $25 FBO plate (to 35 total, initial+slots). what springs are in there? I'm assuming you are on ported/vac adv operational. & we gotta solve the poor idle, I'd start with a basic compression test/idle vacuum. EDIT I saw your 2nd post, bump up the timing/lower the idle speed.

Won't it be running to much total timing and ping. This is a bone stock 318

Its real steady. I thought the same thing at first

No, the $25 plate will allow you to reduce the slots so you can have 35 total. What springs are in there & we can work with them. I think you will be fine with 20 & if it cranks slowly when hot then go back to 15. Initial then total to 35 then work with springs (more on that later) then plug in/adj the can

I'm not sure what springs are on it now. It ran rough at low speeds and taking off. Now its getting worse. Barely can get it to 55 mph. It shakes and chugs all the way to high speeds.

I'm trying to think what that might be & for sure it needs to be dealt with before setting the dist subsystems.

check your plug wires to make sure no crossed wires and correct order on cap and fire order 18436572

3 & 5 are ez crossed and do the same crap.

some times a bad condenser will act that way but you wired in elect. this points me to cap rotor wires plugs.

huck fin someone to run their hand down each plug wire while running.

check BR on fire wall to make sure it is good.

check coil to make sure it is still good.

how many volts at the + side of coil in run mode? how much when cranking

been swapping to a points dist for yrs myself and only have had a bad condenser/burnt contacts/cracked cap/crossed wire act like you describe.

you have ruled out the point dist system so cap/wires/plugs

while cap is off roll engine and check your timing marks and rotor to see where they line up. check wire order on cap against rotor

rock crank back and forth to see how much it takes to move rotor 'slack in the chain'

while looking inside the distributor, check to make sure the advance weights aren't stuck. ran into this a month or so ago doing a pertronix installation for my buddy.

thought about it more driving today....wiped lifter/cam lobe come to mind or jumped t-chain.

if the timing marks all look good and dist lines up correct on cap/wires

pull VCs to see how much rockers move while cranking it over. they all should be about the same and the short ones show up by not rocking very much.

troubleshooting 101

always start with a comp test in each cyl, cranking with carb wide open, all plugs removed.

since the timing mark is steady and if everything checks ok on the IGN.

I wager it is a wiped cam lobe/lifter.

It has new plugs,wires,cap and rotor. I even installed a new dost and coil.removed cap and rocked the motor and rotor turns as soon as I turn the motor.with motor at Tec,the rotor points straight forward at the center of the. Motor.

Actually on the Rotor Phasing you would want the rotor close to the trailing (far) edge of a cap terminal with a reluctor tooth lined up dead center with the magnet as the can will shift it back CCW (on a SB). This is with the rotor retracted all the way CCW which the springs will/should be doing. turn the crank with a 1&1/4" socket/breaker bar. Holler how the compression test goes. EDIT tho I dont think the phasing would be off on both of em (points/electronic). Holler with any new developments.

Is the exhaust plugd