Additional information, to those that might like to know;
The KB spec on those 107s is 1.5 to 2 thou skirt clearance at below 4.10inch bore, and 2 to 2.5 over that. So 4.040 is pretty close to the changeover point. Anyway, I didn't tell the machine shop what to do, and when I got the block back, it was at 2.5. Not knowing any better, I was a little miffed, but it was too late to argue about it, so I put it all together.
So now with the tight gaps, and the unsolvable overheat, I didn't know; was it the rings or the skirts.
What I didn't mention in the previous post, is that, when I tore the engine down. I also had the cylinders honed out a tad more, for additional skirt clearance,at the same time. I used a different machine shop this time, who claimed the holes in the now re-seasoned block were no longer straight. Not having the tools to prove otherwise, I trusted him to do his thing. When I got the block back, the clearance was 3.5thou pretty much every one the same from what I remember. I was again miffed, more than before, but, c'est la vie, I said and assembled it.I checked the KB catalog, and saw that .0035 skirt was NOT excessive,and so the machine-shops were no longer the bad-guys in this story.
With the new specs, that stoopid iron hunk-a-junk instantly settled down.
It had more power, used less fuel, and wonder of wonders, it ran "cold". I was no longer miffed at anybody. I was ecstatic.
But on cool mornings, I could hear the pistons rattling just a tad, telling me the piston skirts had NOT been the problem. So, I installed first a 185 stat, then a 195 stat; and the engine seemed to like it. That Hi-flow 195 ended up running 205 at the stat-house.
The little Hughes 223/230/110 cam eventually went to over 30 mpgUSg on point to point hiway travel. And, with a lil tuning, it would idle down to 500rpm, pulling itself in first gear (manual trans), on a flat,level, hard, surface.
Then I knew I had made the right cam choice. This was now a sweetheart of a combo. I never again missed the 292/108 cam.
Oh yeah, I took it to the track one time. I had a hard time with my shifter that day,and out of 4 runs, only one was any good. On 245/60-14s and with 3.55s, she hit 106 mph at 12.9 and change @3650 pounds and 900ft. Badaboom! The Wallace Calculator says 106 takes 335hp. I was a happy man to be in the 12s. I mean what's not to like about a 12 second streeter that hits over 30 mpg on the hiway, and spins those skinny 245s forever?
Wonder of wonders.
Well, I better tell this part;
That fuel-mileage was made in DOUBLE-overdrive lol. I was using the Mopar od 3+1box, and the GVod behind it, so with 3.55s the final drive ratio was 1.966, and with 27" tires; 75=1830/85=2080,. I used a Holly 600 (1850), that I especially tuned for this run. When we got to our destination, the 750DP went right back on.
BTW: Swapping 4-speeds on a 4-post drive-on hoist, takes less time than swapping chunks, even having to drop the exhaust, and the overdrive unit separately. My record for dropping it all, is 17 minutes.