Rod size?

[69charger]

I bought an Eagle crank that is a 3.90 Stroke for my 400 block that i'm planning to build into a 470 stroker and it calls for a standard length RB rod but,
I was looking at 440 source and their same stroke crank calls for the shorter 6.535 rod so I was wondering...

With my Eagle crank do I go for the shorter rod or the longer one?

 

[69 Runner]

That would depend on what piston you use. The pins are probably in a different location

 

[69charger]

I thought they were all in the same place though?
I've heard of some people running a .60 over 440 piston in a .40 over 400 block.

 

[Meep-Meep]

The 400 block has a lower deck than a 440 so if you put a 440 crank in the 400 and use the 440 piston something has to give and that's usually the rod length. This changes the rod to stroke ratio and some will argue it's for the worse. I heard you can get a piston for the 400 that allows you to use the 440 rod but why go through that trouble when you can just use a 440?

 

[69charger]

yeah I understand the differences in deck height that's why I was wondering what the outcome of using a standard 383 rod would be but i just dug a little deeper and did some more research and decided to go with the 440 length rod.

thanks guys.