There is some good articles out there on the pros and cons of the different bearing types and what they bring to the table .but oh the punishment even oem bearings can take if the clearances are absolutely positively exactly dead nuts on

My block needed nothing done to the main bearing bores. The crank is the factory forged unit that it was born with.

My machinist said that if it weren't for the piston issues that I had (one with slight erosion, and three that made contact with something in their lifetime), there would have been no reason to ever have messed with the bottom end.

I'll be measuring everything with a micrometer and a dial bore gauge.

Coated vs non, I can see the points for either one. I guess it does come down to preference. Mike,thanks for bringing up the clearance change. I thought I had read somewhere that the coating makes a slight change. This confirms it.

tom,coated bearing does change clearance,look at post 8.

Yep, I saw that. Typo on my iPad (digitizer is going south). I'll edit the post. I was trying to thank you for confirming what I'd seen elsewhere.

personally,,I don't run them in my engines,,I save the sixty bucks for other parts.you lose oil pressure for some reason,,coated bearing aren't gonna save chit.
yeah,nascar uses them,probably gives them .0001hp advantage,thats why they put all the coatings on,,they're hoping to get every little hp they can.

but hey,coated bearing look cool.

I'm going to go the route of uncoated. I see where they can be useful, but agree that if something gives up the ghost, the bearings will probably be the least of my concerns. If the crank were to be damaged, I'd replace it versus turning it anyway.

Damn! I was wondering why I didn't have any oil pressure, even with 90 wt gear lube!

Quote Originally Posted by Unlimited jd View Post
Bud man plasti gauge may be be more accurate than your micrometers if you have .025-.027 clearance. I think you meant .0025-.0027






Thats clearance for dry sump motors,no oil just a zerk fitting on end of crankshaft.

I have ran both, I did have the coated bearings help when I split a cylinder wall and got water mixed with oil, saved crank... so it worked, on my current builds I am using non coated just for the fact I am going broke or I would LOL

As far as Plasti gauge, there was a guy on one of my Mustang boards telling me last night that was more accurate then a mike and bore gauge.... WTF?? he said math can be wrong, plasti gauge don't lie... WOW

my guess is math was not his best subject,lol.