Q: Random misfire in race car

asked by on March 21, 2016

I have a race car with a 416-inch small block with about 13:1 compression, and I am having a random misfire.

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If you are running a 13:1 compression in an engine then you will have to have high octane fuel. The first thing to do you should do is to check all the plugs to see if one is fouling out, indicating it is the one misfiring.

Your ignition system may be weak if you have problems accelerating. Check your spark plugs to see if they are producing strong blue sparks. If you still have the old point style ignition then you need to replace the points before anything since this will be the weak link in these ignition systems. If you have changed to electronic ignition then check the plugs, wires, cap and rotor for any indications of the misfire. You can check if the plug wires are arching to ground by using a spray bottle full of water to spray the wires to see if any arching happens.

I recommend having a mechanic, such as one from YourMechanic, come and check why your engine is misfiring.

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