Vibration cause?!?!?!

Car in question:

'64 Dart 170 2dr sedan
360 0.060" over Speedpro H116CP pistons (measured 9.3:1scr)
Stock crank and rods
Comp Cams 268AH-10 cam
340 windage tray
Unported 587 heads with 1.88/1.60 valves
Eddy LD340 intake
Street Demon 750cfm carb
Stock style electronic distributor with FBO plate
Chrysler ignition with an Orange box
'67 A833 4spd trans
Ram HDX clutch
8.25 rear with a 3.55 SG

The issue is I've got a serious engine vibration that I can't nail down. The engine is smooth from it's 800rpm idle up to just over 2000rpm. From that point on a engine vibration increases until just over 3000rpm, then maintains that level of vibration through out the gear. It will do this in neutral or with the clutch in while parked.

When I built the engine I had the entire bottom end balance with the dampener and 360 flywheel. I've had this engine in the car for about 2.5years now, but I don't remember it vibrating like this when I first assembled it.

I've checked the balancer and it hasn't slipped or rotated and looks fine. Like wise my timing marks are still dead on. As far as timing goes, my at 18deg base and 36deg fully advanced. Now here's the part that's got me intrigued, the curve starts off around 2000rpm and is at full advance by 3000rpm. Same window of my vibration...


Could ignition or spark curve do this?!