I use Autolite 23 plugs gapped at .032 for street and .035 for kill.
How do you know he even put the right parts in, ie spark plugs? If he's using the wrong plugs, that may be his problem and would cause breaking-up. Plus, it wouldn't hurt to open his gap more. Giving him an example of what I run and how I set em. Never any issues with regular Autolite 23. They're cheap and just plain work. I'd recommend staying away from the Autolite race plugs if you drive on the street, too. Been there, done that.huh?
I have never seen a wider gap help the ignition with high cylinder pressure. It does the exact opposite. Works the coil hard and can cause mis-fire and engine damage. If he suspects a weak ignition he should close the gap down to .020" and make sure the primary voltage is at least 14v! Also autolite racing plugs are a superior non projected plug for a high cylinder pressure application that is moving a lot of air. Plugs are plugs and will work if the correct type but the gap does matter a lot.How do you know he even put the right parts in, ie spark plugs? If he's using the wrong plugs, that may be his problem and would cause breaking-up. Plus, it wouldn't hurt to open his gap more. Giving him an example of what I run and how I set em. Never any issues with regular Autolite 23. They're cheap and just plain work. I'd recommend staying away from the Autolite race plugs if you drive on the street, too. Been there, done that.