The long awaited return of my block and heads from the machine shop finally arrived. My machinist has been in the business for over 30 years. He only takes projects from people he knows. I had to have a reference from a friend of a friend. He had my engine for almost a year. I finally got to the front of the line and it was worth it. This guy is old school good. Very meticulous with a lot of attention to detail. For example, he wouldn't just bore and hone to spec. He had to have pistons in hand. And even though the crank came balanced and my flywheel and harmonic damper were already balanced, he said they haven't been balanced together and made some minor adjustments.
So I put the freeze plugs in along with the oil galley plugs. Yes, even the hidden one. I considered drilling a hole in the hidden oil plug to spray oil on the distributor and gear, but decided against it. I thought if Pontiac engineers thought it was good, then I didn't want to reduce oil pressure to other systems. It will be much easier to replace a distributor that didn't get enough oil than it would be to replace a crank.
Now there's a thing of beauty! A freshly machined head with those big Pontiac valves. Another thing the machinist did was to put steel seats under the valves. He told me that today's fuels would corrode the lip of the iron around the valve and eventually it would start to leak. So, he put in steel seats to maintain compression for years to come, at least through my life time.
The next step was to calculate compression. To do that, I needed the volume of the heads. A piece of plastic, a syringe, insert a spark plug and fill with water. These turned out to be 30 cc heads, which is what I guessed. I measured a couple of combustion chambers to be sure. After running the calculations, I came up with a compression ratio of 11.2:1 Looks like I'll be running Premium.
After practicing on some of the old rings, I finally developed a process where I could grind them perfectly square. There are a lot of YouTube videos and things where people say to only grind one side so you have a factory side that is perfectly square. I just could not grind one side and keep the ring in a position that would make the grind perfect.
After a lot of trial and error on old rings, and a lot of measuring, I found that if I pushed both ends of the ring into the wheels on my grinder and lined up the side closest to me so that it was barely touching the edge of the crank retaining pin hole, I could get a perfectly square and flat grind every time.
The rings were gapped for a 200 HP shot of Nitrous. I probably won't run spray to begin with and when I install it, I won't use it all the time. I called Mahle and the tech guy told me that on my setup, I wouldn't notice any "blow by" when I'm not shooting the juice, with the extra couple of thousandths I had to take off the rings.
I am very confident with my ring filing. Through this engine building process, I've learned that I have some very minor OCD issues. I always end up measuring things like the ring gap half a dozen times...on each ring. File, check, file, check, file check, check, check, check, ya it took forever. But they are perfect. I used an old piston to position them in the cylinder squarely for the measurement.
I filed each ring to fit a specific cylinder, not that it would have made a lot of difference, but I felt better and then I would move to the next cylinder.
When I finished, I just left all the rings waiting in their respective cylinders so I didn't have to put them on a peg board or worry about getting them mixed up
The pistons were then assembled, valve notches up and crank chamfers out. With the wrist pins drenched in assembly lube. The wrist pins were a "clip in type" instead of a "press in type", lucky for me. I decided to use the Royal Purple assembly lube. I read a lot of good about it, got a bottle and it's super slick yet sticky. When I took this engine apart I found gobs of assembly lube paste in the oil pan and corners of the valve cover area on the heads. I didn't want that. So far, I really like the Royal Purple stuff. We'll see how well it works at startup.
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