crank end play

what is the max you can run k1 crank 7500 rpm

If it was more than .015 I would find out why
The factory service manuals call from .004 to .010 with the stock forged steel BB cranks and the same on the Hemi motors

I like to see .006-.008

I have 12 thou what do you guys think run or not thanks

Yes, I'd rather have 12 than 6. I shoot for 10 on race motors typically anyway. They, for me anyway, seem to hold up better with high thrust loads. I even put a slight bevel at the parting line from the oil groove on the upper bearing to the thrust side to send more oil that way too.

That seems on the big side,they look good when you take them apart??

I have run everything From 3 to 7 to 15 to 22..on a Max effort small-block.. I also had a 408 that somehow Wore into almost 30... no magic in the thrust.. I would say usually anywhere between 4 and 12 would be acceptable.. when the motor is running basically you have zero thrust on the back side..

They look better the wider I run them. Like the other guy said no magic there, unless there isn't enough, then presto. Lol. More oil helps with huge converter loads.

Was this from being to tight?

Here's something I never understood about end play - What are you really supposed to do if you're not in spec? Buy another crank or block? The spec is a fairly narrow window for something you really don't have the ability to adjust. You would think that they would make thrust bearings available +/- .005 or .010.

How hard are you really supposed to pry the crank? If you pry enough it seems like they all have more than .010...

I've lost thrust bearings over the years (who hasn't) and when they are too tight they smear. That bearing looks like it flaked off. Is it a clevite bearing?

Bearing I took out had a bit of that flaking going on ??
Clevite. any ideas

Buy yourself a set of king bearings.