BajaRunner

Probably a dumb question, but what is the process of resizing rods. I always here it and just want to know what is done in that process.

CIG3

They take material off of the rod cap and re-machine by honing to set the rod clearance. There is a little more to it but that is the basic idea. If you have floating pins the clearance would be set for those as well.

Ted G

iTrader: (1)

Cutting the big end and the small end over again to make sure they are perfectly round at a certain spec.

BillK

Baja,

The large end of the rod has to be round and a specific size in order to hold the rod bearing in place and make sure it is perfectly round. After many hours of running, the rod usually distorts some from the factory dimension. This generally does not cause a problem as the engine ages because the distortion is gradual and allows the rod bearings to wear slightly and not fail. Depending on how bad the distortion is, if a new bearing is installed in the rod, it can be distorted bad enough that it will fail soon after the engine is rebuilt. So ... you resize the rods.

To "resize" the rod, the bolts are removed, then a small amount of metal is ground off the rod and the cap where they mate together. Then the bolts are reinstalled and torqued in place. Because of the metal removal, the big end is now smaller than when you started. Next you resize the large end back to the factory size using a machine called a "rod hone" .

That is a simplified explaination. Hope it helps.

Bill Koustenis
Advanced AUtomotive Machine
Waldorf Md

Big Block Billy

Rods should also be re-sized after installing new bolts such as ARP, SPS. It's be a good time to put in new / Better bolts if you are going to have the rods resized.
This should be done with a press by a qualified machine shop. BBB