Ferocity02

iTrader: (60)

I have been looking at engine bearings and am wondering which ones I want. I am putting together a rotating assembly which will use an Eagle 4" crank and probably Eagle rods. The main and rod bearings I'm seeing from Federal Mogul have like +1, +10, +1X, +9, and standard chamfer? First off, what does this mean? Secondly, how do I know which one is wanted, or does it matter? Also, are Federal Mogul cam bearings any good? Thanks for the help!

777

iTrader: (21)

I would just ask a sponsor if I were you. However, I think I'd like to know as well, just for information's sake.

Grimes

iTrader: (3)

the number probably is an undersize or oversize bearing - in case you get your crank turned or your rods resized and need a different bearing (larger or smaller) to go with them.

Mike TexaSS

iTrader: (2)

The 1's and X's are used to provide less/more clearance when using the stock journal size for the application.

The 9's and 10's are used to provide less/more clearance when using a journal that has been turned .010.

If you're using new parts you will end up using STD's, 1's, and X's to achieve the main/rod bearing clearance that you want.

Ferocity02

iTrader: (60)

So is this a hit and miss situation? Should I just get standards and hope for the best?

crainholio

iTrader: (2)

Wow. If you're building this engine yourself, I'm starting a bet-board on how long until the "Why's my new engine knocking" post.

Builder

Ferocity02, pay no attention to the board-polution. You have to learn somehow. However, you should pick up a couple of books on blueprinting an engine. Maybe get some local help. You will need some accurate measuring tools (to the 0.001") to make the right selection for your bearings. Don't attempt it without some reading first, or some local help.

Ferocity02

iTrader: (60)

I'm not building it myself... but I'm assuming the engine builder would like to have the right bearings...

So again, should I just get the standards and hope the clearences work out?

Grimes

iTrader: (3)

well if you are having someone rebuild it, he should know which bearings to get. sorry if it sounds wise-***, but it's true!

Ferocity02

iTrader: (60)

I am buying the parts then he is balancing, assembling, clearencing.

Grimes

iTrader: (3)

you answered your own question - he is doing the clearancing, so he needs to whip out the micrometer/dial bore gauge, do the measurements, and order the right bearings!

Ferocity02

iTrader: (60)

I meant that I was buying the bearings also. So I guess I won't buy the bearings then. Thanks.

So complete rolling assemblies are already clearenced and come with the correct bearings?

crainholio

iTrader: (2)

OK, sounds like you're on a good path here...assuming the guy doing the building has experience with the gen-3 (LS1, etc.) engine. Ask him how many gen-3 engines he's built. If he hasn't done any, shop for another builder. The gen-3 has some new twists in the assembly process that your average builder doesn't know, like torque to yield bolts and oil passage plugs in places the older SBCs didn't have them.