I spun a main bear on my 426 and I’m looking for the best fix. Is there a source for an oversized bearing? If not, I believe Superior Design Concepts make main caps. Does anyone have experience with them? I believe Jerry is a member here. Or is there better sources for main caps? Thanks

You need to figure out why that bearing spun so you can fix that so it won't do that again
Which one spun? How much use, miles on it, before it broke?
I've never heard of larger outside diameter main bearings, you will need to have the block fixed before using it again
Do you have a really good machine shop to use? If not find one They may need to metal spray the bad bearing cap and the block so they can align hone it when done

Jerry's signature has SDC and BCR, and it's BCR that does the main caps.
He's said in the past he could make some for a hemi application and aluminum is the material of choice. there are not any crossbolted caps shown on the website, though.http://www.bcrproducts.com/

I believe Pro-Gram engineering makes main caps to fit most any crossbolted hemi variant, and if I remember correctly their material choice is steel.

If it were mine I think I would probably want the aluminum.

I am here. we have made caps for the hemi engines in the past, need to know what version you have so we can make the right cap. would also need to have your block and new cap line bored to make sure its all good. at that point you might as well get a full set of caps as well.

I agree with Cab. Hemi blocks don't have a reputation for spinning main bearings. I would want to know why it did it. Or we could be right back here next month with the same questions.

Would like to see a few picture of what happened with the block and bearing and crank. Post some and you will likely get the answer or a direction you likely should go in to fix the problem. I agree with Cab and every one else does I would think. Need to find the problem before you can fix the problem.

When the thrust bearing failed it allowed the radius of the crank to limit the oil flow to the back half of the bearings.

Stock 426 Hemi and pre 1973 440 used a very narrow thrust bear. Mopar stroker crankshafts have enough surface area to accept he larger late model 440 bearing so my plan is to machine the thrust cap to accept the larger bearing.

My plan is to stop by the builder to close up some loose ends this week. He was able to line bore and save the block.

You can see how small the bearing surface is with the pre 1973 bearing in the photo.

Man, that's not that bad. Doesn't look like it spun, just starting to chew on it a little. Looks like a line hone to a bit wider housing bore to gain some oil clearance, and a .01 crank turn and you'll be up and running.

What caused the thrust to get torn up so bad ?? would be my first question. the pre 73 bearing should hold up just fine up - unless you have some monster clutch behind it - my guess is unless you solve the crank pushing forward - you will destroy the wider bearing also.

If its an automatic i'd be checking if the converter is preloading the crank. Happens more than you think.

I have a Ram twin disc clutch in it and I know that I have started it multiple times with the clutch pushed in out of habit.

First thing I would check is how far the input shaft of the tranny goes into the crank - my guess is you are bottomed out against the crank - many aftermarket cranks are not drilled deep enough.

This.

I will definitely recheck everything when I get my engine back. I’m sure I will have to recenter my bellhousing also.

A couple things that will help. Like others mentioned, run the wider bearing if your block is cut for it. Have it cut for it if it isn't. Second, at the parting relief, chamfer at the relief from the groove in the upper shell to the back side of the thrust (only towards the back). That will make 2 more direct oiling points into the face of the thrust. Also run the thrust total wide, like .008 to .01. When it's smashed up in the back (on the clutch peddle) the extra clearance will let more oil run through the whole bearing helping it to cool.