Main bearings

[aaronk785]

Can I use 318 main bearings in a 340. I want 3/4 groove mains and can only find them for a 318. Summit lists 318 and 340 mains separately. Its been awhile but I think my 340 currently has 318 full groove mains I got off ebay. I remember grinding to change the upper main locating slot on something.

 

[Plymouth 65]

Yes, main and journal diameters are the same on 273, 318, and 340. 65'

 

[aaronk785]

Thanks 65. Don't know why they list 340 separately. I always thought they were the same.

 

[Plymouth 65]

Just an FYI, I prefer the full oil groove bearing. 65'

 

[383Scampman]

What's wrong with fully groove mains . I have them and they are fine .

 

[aaronk785]

I've always used full groove mains. I just heard the 3/4 are the best of both worlds.

 

[nm9stheham]

Clevite-Mahle lists 273-340 separately from 318. But the mains sets are the same, except that the 318 has listings for 2 different thrust bearings; one has a bit larger flange than the other; the larger flange set is the 1344 PN and is .155" larger OD.