LUVTruck.com

well i bought an msd coil and now it back fires a lot? is the coil bad or something?

You need to be a bit more specific. Is it a Blaster II? Is it installed on the 350 motor or the R22? What type of ignition system are you using? Are you using a ballast resistor?

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Previous setup: 4.1 Buick V-6/TH 350
Current setup: 400 Small Block Chevy V-8/TH 350
9" ford rear end/short bed/blue
What do Water, Electricity and Humans have in common... They all travel the path of least resistance.

I know to two common causes for an engine to backfire. The first is the ignition timing is too far in advance and the second the plug wires are not in the correct sequence. Changing the coil should not cause it to backfire, it will provide a hotter spark but not change the timing.

Oh yeah, a real lean fuel/air mixture can also cause a backfire. The combustion fires too hot and actually can heats up the residual carbon deposits in the cylinder head and cause the mixture pre-ignite during the compression stroke.

make sure you have the 12v hooked up to the + terminal and the ground hooked up to the -. You can hook those up wrong and the car will still run but it will run crappy.

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1978 LUV Truck 2WD
450 "Small Block" Chevy
3.70 Ford 9
28x10 Goodyears

Well had the same problem, someone put a msd coil in it and it, well i started the truck and it started back fireing, so i put a stock coil on it and it ran fine, so rather the coil went bad cause they wired it dirct to the battery or if it was a bad resistor. this was a stock truck and i also noticed that being wired directly to the battery burnt out the points too.