Butler Cobra. Spark plug boots melting

[lal Naja]

Originally Posted by Jerry Clayton

Arthur----

The flow out of those cylinders are away from the spark plug a little bit and a pretty good sized dimple in the header tube wont hurt your performance( it might even increase the flow numbers!) Take a medium sized ball peen hammer and set it on the header tube where you need the clearance and tap it with another larger hammer to indent the tube for a bit more clearance----work it patiently (whats a 1/2 hour added to 10 years?)

Good to hear that you are driving it this summer-----

Hello Jerry, Yes I'm going to do some dimpling on the headers when I remove them from the car. There is insufficient room to be able to make even the slightest hammer tap.

I'm still going to pursue finding a shortie spark plug for a better fit. A 5/8" hex size spark plug would be necessary too. I'm hoping I can use tapered seat plugs too, but I'm still trying to determine what the engineering/design criteria needs to be at the spark plug hole in the head to accept the taper seat plug.

BTY, I believe that running my new engine on the Dyno may not have beeen the best idea. Not sure what could have gone wrong but, I'm blowing a ton of oil out of the PCV 1 1/2 quart in 200 miles. You may recall that I built the engine back in 1987, perhaps parts/rings from that era may not react too well to the high reving stress. I think perhaps I should have followed the traditional break in procedure by driving some 500 to a 1,000 miles before a dyno run.

Hope al is going well with you,

Arthur