ROD TO CAM CLEARANCE GAUGE
Using a plastic banding strap as a feeler gauge works great to check for clearance. The straps are generally .035-.045" thick, so you might want to double them up to check for the minimal .050-.060" clearance recommended. They work great as they easily bend to any curvature you need. If you can't find these straps around, you can always cut any discarded plastic jug or bucket into strips to use. Tip: I have found that on Chevy V8's, rods # 2, 5 and 6 are the ones that get closest to the cam lobes.
Segar Auto Machine
TAPERED ROD PIN BORE MANDREL
Our aftermarket pistons for a LS7 Chevrolet came with SBC .927” pins. The standard LS7 pin is .925”. There is meat in the bushing to hone, but the problem is the shape of the small end of the rod and bushing. They are tapered. It looked like you couldn't just hone like a regular bushing, and we had no special mandrel to hold the rods. It seemed like too much might come off the thin top part of bushing or the bushing would get bell-mouthed. So we made a sleeve to the fit big end of the rods by turning a tube down to the rod housing bore diameter. We shimmed with differential shims so two rods would stay straight and stable. The small end is wider than the big end, so they needed to be shimmed apart. We kept the small ends just touching. They were easy to hone to size now, in pairs.
Bay Speed Center
De Pere, WI
PULL THE PLUG
Removing press in oil galley plugs from blind holes, like a Ford FE block, is a little more challenging because you cannot just pound them out from the back side. First I center drill them with a 3/16" drill bit. Then I install and tighten a lag screw into the plug. Next I pull it out using a claw hammer or crow bar. Quick and easy.
D and D Machine
BETTER ALUMINUM FINISH
For a nice finish on aluminum, I save my chips from boring ductile sleeved blocks and add them at a 20% mix to coarse glass bead in the blaster. I find that it gives the aluminum a brighter finish that doesn’t stain as easy. It removes carbon real well too. It takes a minute to "break them in" but they seem to last quite a while. Keep mixing by back blowing the nozzle.
North Branch, MN
Our shop has had a cam analyzer for over 28 years. I recently had to remembered how we did in the old days when I was at an out of town at a friend's shop. He needed to verify which of the three customer supplied cams to install because the previous shop who had built his engines had ground the name and ID numbers off all three!
I told him to install the cam in his lathe on centers, with a degree wheel on the tailstock end, and to put a pointer on the degree wheel as well. A small piece of heater hose over the tailstock center will hold the degree wheel up against the end of the cam. I then instructed him to put a magnetic base dial indicator on the lathe's cross slide and set it up against a lobe. We zeroed the pointer and the dial indicator. We rotated the cam until the indicator read .050", at that time we set the degree wheel to zero without moving the cam. We then rotated the cam over the lobe until the indicator again read .050" and took that number and multiplied by two. This number is the duration at .050 for that lobe. Do each lobe a few times until you get repeatable results, then move on to that cylinder's other lobe and do the same thing. Then move to the lobe's top and zero the indicator. go .050 down one side of the lobe and zero the degree wheel, then go up over the top of the lobe to .050 down the other side of the same lobe. Read the degree difference, divide by two and set the degree wheel to zero. Move the indicator to that cylinder's other lobe, and zero the indicator again at the lobes top. Go down one side .050 and record the number, then go down the other side of the lobe .050 and record that number. Again divide by two, subtract the one number from the other number again, and that is your lobe center in degrees. Play with a known cam until you get the hang of things and can get good results. You may be off a few degrees off one way or another, but with care you will get close enough to identify an unknown cam.
For lobe lift numbers, just zero the indicator on the base circle, then rotate the cam to the highest number, and that will be the lobe lift. Multiply that by the rocker ratio and you have the lift at the valve.
Tuf-Enuf Auto & Marine Performance