Rod Bearings--Hard or soft??

I was wondering. Rod bearings in a Blown Big Block Chevy. What are everybody thoughts on running hard or soft bearings. Input Please!!

 

We run the hard bearings exclusively now. I believe they have saved our crank a few times when the tuneup was off, or something else went wrong (broken push rods) that would overload the rest of the motor. You are giving up the ability to read the bearings though.

 

Thanks Ken. We have been reading the bearings lately after every run. We wanted to make sure our tune-up was where we thought it was, as in safe.

Since we have verified that, it sounds like we should go back to the hard ones then.

Thanks for the help.

 

hey will talkin bout bearings. we have been spitin them out and bent the crank and the last run we did. we run the v bearing on all of the except the thrust we use an M bearing we use clevite now but we are thinking of changing to a different style any ideas!!!??? anyone?? what bout calicos and there coated ones??? thanks for any help

 

Mike, if you push a V bearing 15-30 thousands you can take it out and replace it. If it was an M bearing under the same circumstances it would be welded to the crank.
Take your pick: V bearings-or-emery cloth.LOL

Federal Mogul has a bearing that appears to be between the V and M bearing in shell hardness.
If you try them, check the width first. A set we got at Indy last year were like .880 wide.

 

hi tom, it is my understanding that the v bearings are harder then the m bearing. so if thats the case it would seem to me that the v bearing would be harder on the crank. dont know mouch about the v bearing we run the m right know. is the v bearing harder then the m bearing. seems to me you would rather hert the bearing then the crank, dont know thats why this massage board is great, thank

 

Because if you push the soft M bearing that hard you push right through it to the steel backing and weld that to the crank.The harder V bearing lives longer after you have established your base tune-up.

 

i still prefer the m bearings in ta/fc. in my past we could run the same set of v bearings all year but cracked 2 cranks. with the m bearings i use the same crank all year but a few sets of rod bearings. in my opinion the soft m bearings act like an absorber for an off tune up. the hard v bearings transfer the heavy load of detonation right into the crank. remember just my opinion

 

Hey, what ever works,works. It just depends on how aggressive the tune-up is. An off tune-up can still pound bearings and burn pistons. Every car/person is a little different.

 

We switched over to the V bearings because we were having problems turning bearing when we really leaned on it. What Ken (my dad) said about saving our crank a few times is true because although it is maybe harder on the crank under normal conditions, it seems very hard to turn a V bearing. We never have turned one (knock on wood) yet in the 2 years we have been running them. Not to say that we haven't had any engine damage in that time, beacuse we have, but there was a few times that if it were an M bearing in there it would have cooked it for sure.

 

hey guys i beg to differ, yes v bearings are harder, but hell i have push out 2 sets on our last 3 runs ive hurt the crank preety bad to where i need to buy a new one so, not every one is lucky, i wish we could fiqure it out cause i'm tired of hurtin my engines!!!!!!!!!!

 

Have you flow tested your fuel pump(s) lately?

[ September 26, 2004, 08:23 PM: Message edited by: rpmhiperf ]