My friend and I were arguing over this. I say that the measurement is taken from the center of the large hole to the center of the smallhole, where as he believes that it is the overall length of the rod. Anyone know for sure?

 

Rod length is determined center to center. It does not matter what size piston pin you run or what dia. the rod is.

 

That's what I thought. Thanks

On a side note how can you tell, if a crank is just sitting on a table, what stroke it has? I've started going to swap meets looking for parts for my new stroker motor I'm putting together and want to be able to know what I'm looking at.

 

Dont know about measurements, but get the casting number and look it up on www.mortec.com

 

I'm reffering to aftermarket cranks, not stock 400 cranks. Thanks though. Mortec is one of my saved wedbsites.

 

Stroke is determined by the distance from the center of the main journal to the center of the rod journal. This distance is one half the stroke.

Measureing this on a crank just laying on the bench i think would be difficult.


I have a diagram attached that should help explain the calculation. I used a 305/350 crank as an example. A 383/400 crank would only expand the distance between the rod and main centerlines by 1/8" (.125"). I think you would need a rather odd set of offset calipers to measure the crank out of the engine.

Hope this helps

 

Sorry guys, Here is the diagram I referenced