Bearing clearance optimisation.
- Thread starter Shannow
- Start date
- Status
I like the fact that the author talks about distortions.
These are mine;
A crankshaft will be progressively loaded higher towards the drive end of the engine, causing "wind-up and let-go" events.
Shifting under power can cause the crank to flex.
Due to harmonics, an engine could have a bad spot in the rpm range.
There are so many variables, that perhaps the best practice when rebuilding engines,
would be to open up the clearances, run a thicker engine oil than popular opinion and make sure the oil pump can keep up with the program.
I grabbed this gem from the article;
"In order to prevent or reduce metal to metal contact,
the clearance should be designed
to produce the maximum possible level of minimum oil film thickness.
I had to read that one a few times to get what he was saying.
These are mine;
A crankshaft will be progressively loaded higher towards the drive end of the engine, causing "wind-up and let-go" events.
Shifting under power can cause the crank to flex.
Due to harmonics, an engine could have a bad spot in the rpm range.
There are so many variables, that perhaps the best practice when rebuilding engines,
would be to open up the clearances, run a thicker engine oil than popular opinion and make sure the oil pump can keep up with the program.
I grabbed this gem from the article;
"In order to prevent or reduce metal to metal contact,
the clearance should be designed
to produce the maximum possible level of minimum oil film thickness.
I had to read that one a few times to get what he was saying.
used_Oil, there's a reason that the old straight 6 (and 50s V-8) architecture of a flat bottomed block along the line of the main bearing part line is gone with the dinosaurs, and I'm pretty sure that it's block and crank rigidity.
Get The block rigid, and half the work's done.
Go to narrower, larger diameter journals, full counterweights, and the work is progressing in the other direction.
Critical speeds on the turbines soak up whole thousandths of an inch
Get The block rigid, and half the work's done.
Go to narrower, larger diameter journals, full counterweights, and the work is progressing in the other direction.
Critical speeds on the turbines soak up whole thousandths of an inch
Originally Posted By: Shannow
used_Oil, there's a reason that the old straight 6 (and 50s V-8) architecture of a flat bottomed block along the line of the main bearing part line is gone with the dinosaurs, and I'm pretty sure that it's block and crank rigidity.
Get The block rigid, and half the work's done.
Go to narrower, larger diameter journals, full counterweights, and the work is progressing in the other direction.
Critical speeds on the turbines soak up whole thousandths of an inch
Sounds like you are describing four pot turbo motors to me.
used_Oil, there's a reason that the old straight 6 (and 50s V-8) architecture of a flat bottomed block along the line of the main bearing part line is gone with the dinosaurs, and I'm pretty sure that it's block and crank rigidity.
Get The block rigid, and half the work's done.
Go to narrower, larger diameter journals, full counterweights, and the work is progressing in the other direction.
Critical speeds on the turbines soak up whole thousandths of an inch
Sounds like you are describing four pot turbo motors to me.
I can think of one such dinosaur going down the 1000 foot rather quickly.
Originally Posted By: ragtoplvr
Originally Posted By: used_0il
I can think of one such dinosaur going down the 1000 foot rather quickly.
If the dinosaur is a hemi, they have always had deep set main caps with tie bolts.
Rod
Yep.
Originally Posted By: used_0il
I can think of one such dinosaur going down the 1000 foot rather quickly.
If the dinosaur is a hemi, they have always had deep set main caps with tie bolts.
Rod
Yep.
Don't order a 48 degree cam for a 45 degree factory hemi block.
Olds owners got caught on the 39/45 degree block/cam thing, ordering a 455 cam for a 425.
Made the engines sound like a Harley.
Olds owners got caught on the 39/45 degree block/cam thing, ordering a 455 cam for a 425.
Made the engines sound like a Harley.
- Status
Similar threads
