Numbers, numbers, numbers

After doing all the chambers 3 or more times I came up with an average volume of 60.4 cc. The lowest was 59.6 and the highest was 61.0 The spread from average ranged from -.8 to +.6. I have been emailing with Jim Pepper on this project as I need a lot of help since this is my first time doing it on a V8. According to Jim + or – 1 cc from the average is acceptable.

Not willing to leave well enough alone I decided to work on the cylinder that was only 59.6 cc. It was the one cylinder with bad pitting. The exhaust seat was so bad it had to be replaced. This is what it looked like after a small amount of grinding. I left the valves in to protect the seats while doing the grinding.

I put a small grinding wheel on my electric grinder and smoothed out the chamber.

After this bit of grinding the volume jumped from 59.6 to 61.3 to become the largest chamber! Working the numbers the average is now 60.6 cc and the spread is from minus .6 to plus .7. Still within the range of ±1 cc.

Jim commented that it would be a good idea to radius the sharp point between the ports – see where the top bar of the caliper is resting. He said I should remove only a small amount of material.

Here is one of the chambers with a very small amount taken from the sharp point between the valves.

Next I’ll take the heads back to the machine shop to get .010 planed off to bring the compression back up.

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