heard the words that strike fear into any racer...NATIONAL BACKORDER when i asked my machinist to order some king main bearings for the 470. took vacation hoping to get this heap at least to the long block stage. not really familiar with different main bearing options for this. much rather use 77's over FM. what are the different bearing styles you guys are using? are there any concerns with the thrust size? should i just use standard full groove trimetals? iirc the kings are full groove. who sells the 3/4 grooves i've seen mentioned?

thanks

I have simply been using MS876P bearings. Full groove. They are designed for the early blocks, but can be used in the late '70s blocks also (but the late thrust bearing can't be used in the early block).

OK thanks Jim, that's what i figured i'd end up using. i just really like the Kings and have had no problems with them. i like the fact that the outer layer of material is >.010" thick as opposed to standard bearings. Monte Smith has also remarked that their tolerances have been better than other bearings from his experiences. imho it's a shame they don't have a larger selection of chrysler bearings but as you it's a supply/demand thing.

What’s the differences on the thrust bearings on the B blocks??



Or is this a RB block yous are talking about

Called Clevite bearing (734) 975-4777 for specifications on bearings.
'73-earlier MS876P thrust surface dia 3.370-3.410, overall dia 3.430-3.500
'74-later MS1348P thrust surface dia 3.665-3.695, overall dia 3.720-3.780
They call the thrust surface dia. the chamfer dia. and they attempt to hit
the center of those tolerances.

thanks Jim...i'm thinking the only possible issue would be the recess in the cap/block as this is a 440 crank and i "assume" (scary) the crank thrust would be bigger or at least as big as the larger 400 thrust...guess i gotta get out the yardstick.

I measured the thrust surface on a couple of my "440" cranks. Both were ground to use in the 400 block, and one was offset ground for more stroke. One of them had a thrust surface large enough to cover the large 400 bearing, the other didn't. As I recall, one side of the thrust was bigger than the other too. Remember, the 440s changed thrust bearing size too, but most of the "late" ones were cast cranks.