Need advice cylinder scratches

Ok so ill try to keep this short, Ive been building this old Cuda for about 5 years now and I'm almost ready to fire it up. I had this 408 LA built about a year ago, I had to swap oil pans because the Moroso It came with sat to low to the ground. when I pulled the pan I could visually see up and down scratch marks in cylinders 3,5 and 4. I couldn't really feel the marks with my finger but they were there, Unfortunately I didn't have the for-site to take pictures. The engine was only run for the dyno and I was pleased with those numbers. (I didn't see it run.)
After much digging around the site I've come to the conclusion that there probably from the builder failing to clean up the ends of the rings (debur). At the time I told myself it would be fine and just to run it and see how it goes. But I cant seem to get it out of my head! Is it something i should fix before I start it up. I know what everyone is going to say. Send it back to the builder, but logistically that's a nightmare for me and I'm not sure I'm willing to wait another 6 or 7 months for them to get to it and its a couple states away. So the question should I go ahead and run it and see how it goes? What damage do I risk by running it? Would the smartest thing be to just tear it down now? 408, fully forged, KB pistons, 10 to 1 CR, eddy heads, Howards cam.


I talked to the builder, im going to fire it up and run it for awhile then do a compression test, they said they would stand behind there product, so worst case scenario, ill have to pull it and send it back to them. Sucks but at least I have a little piece of mind.


If you couldn't catch your finger nail in the scratches, then you should be ok...

Also, as long as the scratches did not make any metal proud (higher than the metal surrounding it), you should be ok... (If the scratches went below the surface and not above it and not too deep, you should be ok...)

The worst that can happen is you can get some blow by...

I would do a compression check, and/or a leak down test to see if it is affecting the sealing of the rings at all if you want a piece of mind without tearing the engine down again...

If anything, as the cylinder wears, it should make the scratches smaller and less affect on performance...

Keep in mind that combustion is pretty instantaneous and there is very little time for the small scratches to leak unless they are too deep, and if they are you should have been able to catch your finger nail on them when running it across the scratch.... Run the finger nail perpendicular (90°) to the scratch to check...

We used the finger nail test at the engine factory to tell if we could run with the issue or not on cranks, head surfaces, cylinders, etc....