OleRustang

I just bought a 1989 Coupe LX Conversion Car to a 302. With a Holley 650, Msd Ignition, Edelbrock Performer Intake, b303. I got it off a guy that was holding the title for someone that owed him money and he didnt know alot about the car. When I bought it it was skipping and he said it was out of time. I hooked up the timing light and set it to 10* BTC and it idles fine without skipping. But when you start to give it gas to take off you have to ride the clutch in order to get it to go. While out on the road crusing at lets say 45mph steady on the gas you can feel it "bucking". If you stomp it to the floor it pops and misses evens out a little but not fully then backfires when you let off. (bbk long tube headers flowmaster series 10's) I have fooled with it a little but cant figure it out. Any ideas would be helpfull. This is my first carb mustang.

mustangGT86_05

He may have meant valve timing rather than ignition timing, which sounds like a good possibility.

nitrous_bob

are all the plugs in the correct firing order ? and all "snapped" on

spark is usually the culprit over fuel, so make sure the firing order is correct, the plugs are gapped properly (i like small gaps, like .042") and copper plugs, not platinum

did u time it right ? spout out, change, spout in ????

4rdnut

The msd ignition box could be bad. I bought a brand new msd ignition for my 460 tbird and it lasted two months before strangely acting up like yours is doing. I changed over to a crane cams hi 6 ignition and never had a problem since. Try a backup ignition if you have one or use a friends ignition to see if the msd ignition is the culprit.

projectresto83

No spout on a carb car ....BUT there is a vac advance which does the same thing lol so it would be vac line off and pluged then check the timing.

Your distributor might be a tooth off. It can still idle fine but once the timing start advancing while driving it will run like crap.