Here's a picture of the whole thing put together... Final setup is a 49 tooth lower pulley and a 56 tooth upper pulley for a 12.5% underdrive. This will give 8 pounds of boost and with the static ratio of 8:1, will give an effective compression ratio of 12.4:1.
I also have a Powermaster 140 amp alternator mounted low on the motor for now. Once this gets in the frame, as long as there are no clearance issues, I'll keep it there. Looks ugly mounted up high.
I'm going with a pair of BG Mighty Demon Blower carbs...650 CFM each, mechanical secondary, no choke.
Now all of this comes off. I'll be starting the engine for the first time with the original AFB Carter carb and stock Hemi manifold. Once I get it up and running, with timing set, I'll put on the blower. One thing at a time....
I'm using a BDS 8-71 blower and drive on the Hemi and wanted to mock everything up to verify everything fit. First thing to do was to level-up the engine block. Used the valley cover surface and shimmed engine stand so that all was level. I figured it would be easier to make sure that everything lined up.
The blower manifold is a Weiand # 7138. As I mentioned in earlier posts, since the heads were shaved to fine tune my compression ratio, it also lowered the intake ports and bolt holes. A corresponding amount needed to be shaved off of the manifold to get everything to line up again. Manifold fit up fine and all is still level and parallel. Next came the blower case, and again all looks good.
Next was the installation of the pulleys. Here's where I had some fit-up issues. The pulleys I got were too big. They were the correct ratio, but both needed to be smaller in diameter so that the belt would fit and I would have some adjustment on the idler pulley. Also the top pulley spacer needed to be changed so that the fronts of both upper and lower pulleys lined up.
Once I got the correct pulley spacer and pulleys, everything lined up perfectly.
Once the hole was the right size for the wire, I found out that the terminal end of the insulator had to be enlarged also. It seems that although the terminal would slide in to the correct depth (there is an internal lip that the terminal seats against), there was not enough room for the terminal end to open up so that it could snap over the spark plug tip. Out came the die grinder with a solid carbide grinding tip, and I opened up the terminal end where the snap ring portion of the terminal is located. Opening it up to .375" was enough to get the spark plug to snap solidly onto the terminal. You may be able to see in the picture a mark on the carbide bit that I used as a depth reference. I didn't want to go too deep and hit the internal lip that the terminal seats against.
After all of the "machine work" was done, it was time for assembly. I used all Taylor wire products including their 8mm Spiro-Pro wire, straight terminals, and crimper.
After all terminals were finished, and I snapped one on a spark plug, I noticed that the insulator would "rattle around" on the plug. This was because of the fairly large gap between the I.D. of the insulator and the plug insulator.
I wanted a nice snug fit on these things, just like on modern plug wire boots that grip the plug insulator. I ended up making my own silicone insert. I first put some silicone grease liberally over the spark plug insulator and inserted it in the terminal, squeezed in a lot of black RTV silicone around the plug, and let cure. After curing, I removed the plug, trimmed the RTV, and now have a "modern" ceramic Hemi spark plug boot. It holds the plug nice and firm with no rattle. This was a big job, but I'm glad I did it.
I wanted to use the early Hemi ceramic spark plug wire insulators, but since they were made for some pretty skinny plug wires, the modern 8mm wires that I am using won't easily fit. I needed to enlarge the through-hole in the insulator. The stock hole in the insulator is about .295-.300", and I needed to go up to about .314".
I came up with a way to do it by chucking a piece of 1/4" steel rod in the drill press. I coated the rod with sanding disc adhesive and stuck some 80 grit silicon carbide paper to the rod. The carbide paper seems to be about the best stuff to cut the extremely hard ceramic.
Running the press at moderate speed, I rotated the insulator on the rod and also moved it up and down, kind of like an oscillating spindle sander works.
I checked my progress with a dial caliper until I had the right size hole. Towards the end of the effort, I found that it was a lot easier to just keep on grinding until a 5/16" drill bit dropped through the insulator.
This job took FOREVER! It was not the most efficient way to do it, and it took many hours to do all eight, and I went through many sheets of sandpaper to do this. If I were to do it again, I would try to find a business that worked with ceramics and have them bored out. Maybe a diamond type hone would be a lot faster.... If you want to try this, be prepared for many hours of work!
I liked the look of a Vertex magneto, so I decided on the Vertex HEI "Mag Style" electronic distributor. Its completely self contained and ready to run, and it will clean up the engine compartment a little by not having a separate coil. Sweet....
Plug wires are Taylor 8mm Spiro-Pro silicone. I bought the bulk wire, terminal ends for the plugs and the crimping tool and "rolled my own".
I didn't want to use the stock wire covers, so when I had the valve covers re-conditioned, I had the wire cover stands removed. By using a flanged style spark plug tube and the matching tube seal, I don't need the covers.
Also seen in the photo is one of the things that I am real glad of having taken the time to modify and use. I always liked the porcelain (ceramic) spark plug insulators on the very early hemis and decided to use them instead of the aftermarket modern stuff. It took a lot of work to make them work with the heavier 8mm wire and terminals, but the work was worth it. In an upcoming journal entry, I show how I modified them.