Re;”Another clever idea shot down. With the .065" shims, the cam just barely rubs against the bronze lifter blocks. I could make up some thinner shims, but that wouldn't give me as much overlap as I'd like when the lifter is on the base circle of the cam. I need some safety margin when the engine is running at 8,000 rpm and the cam is flexing. Instead, I'm trying to copy what Herb Becker did in a similar case, where he extended the lifter body by combining two BSA lifters to make one with a longer body. I'm doing it a little different, by welding a couple of 1/8" spacers to the top of the lifter base. I cut two junk lifters into pieces to make the four spacers I needed, and then tig welded them onto the top of the body. The welds don't look that great, because I was being very careful to not get the lifters so hot that the braze joint melted and the carbide base came off. I welded one side at a time, with the lifter sitting in a wet rag, and used a high current to keep the welding time as short as possible, cooling it immediately after with another wet rag. I didn't try to get a beautiful bead all the way across, just enough to keep the spacer on. Next step is to re-assemble the engine and verify that I still have enough travel for the lifter. If that doesn't work, I'll have to go to plan B, whatever that is.”
IMO welding would be better when joining two parts with butt weld if you grind 45 degree on each of the side to be welded. You would get a much stronger weld.
. I could see the wear marks on the lifter block edges where the lifters had almost come out of the blocks, and apparently rotated a tiny amount, then hit the edge of the blocks as they dropped back in. I measured the height of the base circle and of the top of the lobe below the cylinder base, and compared that to the height of the lifter below the base. It looks like I have enough room to shim the lifter blocks about .060" further out. That should prevent the lifters from coming out of the blocks, but still leave a little (very little) clearance between the lifter blocks and the cam lobe at full lift. I made a couple of .065" shims to raise the lifter blocks, shown in this picture. I'm hoping that works, but I still have to assemble the engine again to find out. If that doesn't work, I'll have to do something more involved.
