I am curious how wide the big end of the rod is and if it is important... Basically I want to use a chevy rod for another application for cost reasons and found a rod that will work well and is off the shelf but may have a slightly larger or smaller width. Is it used as a guide against the crank to prevent walking along the journals?

 

try to avoid huge side rod clearance, it can lead to alot of oil being slung around in the crankcase and can lead to a loss of pressure, and a few other things. but to answer your question. a stock lt1 5.7 rod mearues about .950" as for the other application what exactly did you have in mind.

 

I use Manley rods that are made for a standard small block application and have never had a problem. Side clearance should be monitored as you put the engine together. If the clearance is too tight you will likely experience a catastrophic failure. If the clearance is too loose you will have exactly what WS6T3RROR describes. Not necessarily catastrophic but certainly not optimum. I prefer between .015 and .025 but most of my motors see race use only.

 

Porsche v8.... stock rod side clearance is .006-.021 in the lt1. Thats a pretty damn big spread Ill have to see what it is in the porsche motor along with rod width and hopefully it is smaller, but I doubt it will be... this engine has the same (damn freakin near) bore spacing as a 440 big block mopar. However the rod journals were only slightly larger at 2.165, I have a feeling the journal will be wider than .95".

EDIT: Yeah they are 27mm wide, or 1.063".... damn thats nearly 3mm difference. As long as I can get one only slightly bigger I can shave it down to 27mm I'm sure. Be cool if you could put round flat bearings or maybe roller bearings in there to make up the diff but the crank doesn't come apart for that, lol.