Do you have to grind the crank or do you have to offset a crank to stroke an engine? The following items I know:
The bore size is 4" (do I need to change that?)
The crank is nodular iron with mains being 3" and rods being 2.311.
I know to stroke a 351 W, you use a Chrysler 6.125 rod which will change the stroke to 377 CID.
Does the piston pin change or is it the same size as the 6.125 Chrysler rod?
On the crank side, is the rod the same size as the Chrysler rod?...understanding the Chrysler rod is 6.125 long.
What engine does this rod come from in the Chrysler?

 

No matter what you do to the engine, if it doesn't require an overbore, IMO leave it alone, your not gonna gain much in the way of hp vs the ability to reuse the block, no you don't have to bore it to stroke it.

The length of the rod plays no role in factoring the cubic inches of an engine. Only the stroke and bore give you cubic inches. A theoretical example only...you stick the 6.125" rods as opposed to the stock 5.9" on a stock 351w crank with pistons that would be flush with the block deck surface....you would still have 351 cubic inches.

YOu can offset grind the stock crank to stroke the engine.

An easy combination would be a 393 scat crank, your stock rods, and stock 302 pistons using what ever over bore you have to go with-if the block doesn't need an overbore then use stock 302 pistons....this method is fairly inexpensive...as you have the rods and 302 pistons are cost effective....no matter combination of crank/rods/pistons you use the entire rotating assembly will need to be balanced using your damper and flywheel or flexplate...no matter if you use your stock crank or aftermarket.

The main thing with offset grinding the stock crank is strength of the crank and cost of machining...thats why many just opt for the scat cast crank.


What are you trying to achieve cubic inch wise...are you trying to build a 408 using the chrysler rods? With the length rod you posted, with a 4" crank (aftermaket or a 400modified crank with the snout machined down) and the right pistons, you could get in the neighborhood of 420 cubic inches.