3 inch mains on Hemi?

Just wondering if anyone has had any luck running 3" mains on a blown alky combo. I recently split my block. I have had trouble finding a good used block. I found a deal on a stage 16 KB new in the box with 3"mains. My question is should i not go this route? and why?. thanks im new to promod racing.

 

the 3 in. main deal didn't last to long.

 

Why was this as it seems to be a great deal?

Were bearings not readily available?

Were the main studs too close to the main bore and it would crack there?

Did it not make the cranks last longer?

 

I ran 3" mains for 10 years and had a total of 4 blocks during that time (destroyed one but not due to main bearing size).....but the size of the crank journals, mains and bearings did not seem to make a difference....some say the bearing speed is increased and makes for more heat or friction but I had no oiling problems at all...used a System One dry sump with 20 quarts on board....I heard that Bernstein started the 3" main option when he opened up blocks with spun standard bearings to 3" and used Ford 460 or Olds bearings...seems like it was late 1990's....3" main cranks are getting a little hard to find if you want a decent used one....and I have only seen them for sale used with 4.500" stroke....

 

3" bearings work just fine. The real problem is sourcing the bearings and getting the mix of sizes and materials that you want/need. You might want to find out exactly which 3" bearings that block is set up for, and what thrust bearing.

The Olds 3" bearings are almost nonexistent and available basically from one source. When that source is used up, the supply will not be replenished from what I am told. Clevite tech tells me the Chrysler 3" bearings are also going away in the not too distant future. The Ford 3" bearings are more available. The thrust bearings are all different for all of these combinations.

If that block is setup for Ford bearings then you can easily have a crank made to work, but doubtful you will find anything used to work. Depending upon the price, you could also rework the block to accommodate standard bearings. Unless its a really good deal, I'd pass and go straight to a brand new billet block and never have to worry about block failure ever again.