Don Terrill’s Speed-Talk

I tend to agree, but that stupid desire for perfection can be a sickness:)

A fellow with an engine (balanced), reassembled to the rotating level damaged a piston. The replacement piston is 7 grams lighter (547 vs 554). I am sure the best thing to do is just install and go, but.... it sure would be nice to get it within a couple of grams, so I started reading about peoples ...

Bill, There is not a target bore size on the box. What is on the box, is a minimum clearance of 0.001", and a skirt size of 4.18375". Looking at the two charts I have that compare usage of the same piston in automotive and marine applications, it looked like the marine was 150% to 200% lar...

I am only doing the machining, I am not assembling it, I did not disassemble it. It is getting a marine camshaft that can run to 5500 rpm. So there are a lot of unknowns.

4.1832", 4.1830", 4.1834", 4.1830", 4.1833", 4.1832". 4.1830", 4.1832"

An Olds 455 standard bore of 4.126" which becomes +0.060" bore of 4.186" The nominal piston size is 4.18375" (I haven't checked the size yet), so with 0.001" suggested clearance the bore size would be 4.18475" and if I target a clearance of 0.0025", the bore size w...

I have a '74 Olds 455 that is going in a boat and wrestling with Piston to Wall Clearance.
The pistons are Sealed Power L2323F60. The box says 0.001", I am thinking at least 0.002", and probably 0.0025".

Thanks

It looks to me that if you reduced the clearance, opening on the secondaries, the engine would have to draw more air past the primaries and you would have to open them a bit which would put them closer to where you want them.

May not be your problem, but if you are working with the 4150 and 4160, make sure the secondaries are closing. I am pretty sure they have a secondary idle screw just for the purpose of leaking air past the secondaries. The purpose is to eliminate the need for drilling holes in your primary throttle...

May not be your problem, but if you are working with the 4150 and 4160, make sure the secondaries are closing. I am pretty sure they have a secondary idle screw just for the purpose of leaking air past the secondaries. The purpose is to eliminate the need for drilling holes in your primary throttle ...

Just a thought, what about using the current pin (you have it) and putting a 27 gram slug in it. Perhaps a light fit with some Loctite?

I am a bit of a backyard shop, but I bake at 750 degrees. I also use the oven for cast iron welding, and go somewhat higher than that. For long cool downs just make it the last job of the day and leave it in the oven. My old oven is still warm 14/16 hours later. I have read articles where bake ovens...

When preparing pistons for thermal barrier coatings and dispersants, etc., techline and probably others blast the piston with Garnet or Aluminum Oxide. This prepares the surface for the coating. It would definitely clear and minor starches which sounds like your prime objective. Perhaps you could ju...

ProPower engines wrote: ↑Sat Jan 29, 2022 2:33 pm Wow old thread back to life again

What model of machine is that??
Wondered if a KO lee valve refacing machine could be converted as they are collet chucks.

It is a KO Lee BA960

FWIW: You can make almost infinite number of radii by using the inside surface of a cup grinding wheel. If the wheel face is perpendicular to the lifter bottom, the lifter will be flat. If you angle the wheel mount, such as turning the compound on a lathe with a tool post grinder, so the bottom of ...