Technical Decode SBC bearing P/N?

I’m trying to decode the main and rod bearings in my 350 Chevy small block so I can order new ones.

Rods- 10 90
CB 663P
E1

Main- 1 89
MB 2508 P
LOWER T

Thought maybe someone here that was well versed in engine rebuilding may know what undersize these are. If not I can take the crank to my buddy’s shop this weekend and have him use his fancy micrometer type tools to figure it out, but I’d like to get them on the way soon as possible.

Thanks! -John

 

I’m guessing the rods are .010 from the “10”, and the mains are .001 from the “1” marking, but I’m not positive.

 

Are you sure these aren't standard size? The part # is Clevite 77 and any of these I've seen have the undersize stamped right after the part #. The first set of numbers is the month/year manufactured. The CB is connecting rod bearing and MB is main bearing. I would mic the bearings and crank to verify. You really should mic the crank anyway to make sure the bearings you use have proper clearance.

 

.010 .010 is what I come up with. Main only has a 1 not follow by a zero per other vendors.

 

They are STD STD Clevite. IE .010 under would be CB663P-10
https://www.summitracing.com/parts/...MIoqTP1bPE_wIVzEZyCh19UAMsEAQYBSABEgLnQ_D_BwE
The -1 on the mains above would be .001 under.
- nothing is STD
1 89 and 10 90 are likely dates
You should always torque & check your rods & mains and mic the crank to verify your oil clearances.
They are probably the easiest bearings to find on earth. Mike

 

Mike has you figured out...standard size, made almost 35 years ago.

Always measure the crankshaft before ordering bearings.

Also, if the other side of them still looks good, you can reuse them....it's a little known trick I use whenever I can.

 

Thanks guys, I really appreciate the info! I’ll have my buddy check this out for me before I order, definitely not trying to cut corners to get them a few days early.

Thanks again! -John

 

That’s what I get. Stupid search goes where it want’s when not paying attention.