318 Running Rough / Backfiring

Hey guys,

I have been researching this and I am not sure what's going on. I wanted to see what all the FABO experts think :)

The car has been running great the last few months. Just today I get in and it starts running really rough on idle and acceleration. Has some backfiring when accelerating also.

Car: 1974 Dodge Dart Swinger
Engine: 318 Bored .030 with KB pistons
~9:1 compression
Indy LAX heads
TTI shortys, full exhaust
Eddy air gap, Eddy 650 with elec choke
Comp Cams XE268H (Duration @ 0.006": 268° / 280°; Max Lift w/ 1.5RR: .477" / .480"; Lobe Separation: 110°; Intake Centerline: 106°)
Trans: Rebuilt 727, shift kit, stock converter
Rear-end: 8.25, SG, 3.21 Gears
Rev-n-nator
MSD blaster 2 coil
Initial timing set around 15°
Also running a Summit distributor

_____

-I have checked vacuum lines, nothing is disconnected
-Timing is still good