Couple of Bearing Questions

With blown alcohol, and Clevite main/rod bearings, what are people having the best luck with these days? V or M ? Could a person get by with an H on the mains?

 

How much power or how fast are you trying to go?

 

TAFC type power....

 

V bearings - M bearings will flake and cause rod / crank failure - VERY QUICKLY - as in 3-4 passes. M bearings have a .0003 tin plate - thats what flakes off - if you make 1000 hp the M bearing is fine - otherwise the V or Vandervell bearing is required - ps I have five damaged cranks from M bearing use - been there done that - free research and development for you!

 

what about the H bearings?

 

Clevite Tech does not think an H would be good, but I wonder if anyone has actually tried one ?....

 

do they make a bearing in sizes .030 and .040 rod and mains for light blown use 1000 to 1200 hp thx

 

hi what main and rod clearances do you run?

 

Hello,

I'm new to the forum and was actually looking for information when I came across this thread.

I have ran FM Clevite H bearings in a 364ci blown alcohol SBC with 11.5:1 SCR and did not have any problems that could be attributed to the bearings. However I did have bearing problems that were caused by the SBC block. The main bearing caps like to walk around which resulted in iron flakes being fed to the rod bearings. I made a set of billet steel main bearing caps and used heat treated 4340 alignment sleeves that were placed in the outboard bolt holes (4 bolt caps).

That eliminated the main bearing caps walking, but the rod bearings were showing some shiny spots. I had long ago taken care of the ZERO oil pressure at launch and chute deployment so that was not the cause for the rod bearing problem. After intensive consideration I had no solution so I started reading (no internet) through the FM bearing catalog and what I came up with was main bearings with a full (360°) annular oil groove. The original bearings had a half (180°) oil groove which shut the oil flow down when the oil transfer hole was in the bottom (main bearing cap) side of the bearings. That resolved the rod bearing problem.

Fortunately I was able to survive all of the bearing problems without loosing my crankshaft. That was due to my Hank The Crankshaft with hard chromed crankshaft journals.

In many cases it is not as much the fault of the engine component as it is the engine builders failure to provide the proper operating conditions.

I have been away from racing for over 33 years. I'm currently building an Anglia which will be powered by a 400ci blown alcohol SBC. It's the only combination that I know. This car is being built for the street, but the engine will have all of the killer parts.

SM