I'm working on a 350 from possibly an 87-95 truck engine. It's center bolt v/covers and 2 bolt main. This is a rebuilt engine and may have been done more than once. I tried a search but found nothing for the stock ID measurement of the bearing side of the connecting rod. I think it has been honed out and need to confirm so I can order the right bearings this time. So if you can help I really appreciate it.

Mike G

 

The engines came with several slightly different size crank and rod journals ,3 possible sizes if I remember, so you need to mike all the crank journals and aks the bearing manufactures for the proper size bearings. Also, you could check the current clearances with plasti gage, do the math, and ask for the proper under size bearings.

 

Pete, the problem I have is not the crankshaft undersize but the resized c/rod to the outer shell of the bearing. I rechecked with Napa and the guy says it is the right part# for .002 resized rods but I think it's mispackaged and the guy doesn't want to reorder. I spoke to my local machine shop and he said the proper way is to replace the rods. Some rebuilders will hone the c/rod hole and stick slightly larger shells to cut cost but that's not how he does it. The funny thing about it is only #1 and 3 c/rod bearing have rubbish in them. The rest are clean so I think someone didn't flush the oil holes properly. I've had so much problems getting parts for this engine. It had oversize valve stems with the wrong intake seals as well as hammer marks on the fasteners.

 

I've always understood what you described the machine doing to the rods as "reconditioning" the rod so that if the hole becomes elongated you can return it to its circular shape and slap oversize bearings in there. That way you can spend less on the rods and reuse them. Some people spend 500 bucks or more just on rods and don't want to just throw them away if that happens. Just recondition them and slap them back in.

Connecting rod length center to center should be 5.700 inches for a stock 350. They were on mine.



EDIT> OH, just reread your post... on my stock crankshaft when I pulled the rods the stock area was 2.100 in diameter without the bearings on the rods. So if you slap in the bearings it's probably going to be 2.0000 with them installed. Atleast on stock.

 

thanks Kyphur, mine actually measures in at 2.227. I found the measurement in my Blueprinting chevy book. It list two sizes 2.125 and 2.225. I dropped off the rods yesterdayto the machine shop because he said he as a good used set for cheap that are not stretched or oversized. This way I can order basic .010 under and be done with it. Thanks for all the input.