I am building a 454 for my 71 Chevelle and I am going to buy a new crank. It is asking for a 4.000 or a 4.250 stroke. What is the difference and how do I find out which one is for my block. I have a 73 4 bold main block and it is a 289 block. Thanks for the help. JP

4.00 stroke

Dave

What is the difference? In the books Jegs, Summit they show both. What is the 4.250 for? JP

4.25 stroke with the proper pistons gives you a stroker engine. This increases the stroke, increasing the displacement to 496ci.

4.00 is standard for 454

A 4.00in crank, as already mentioned, is the standard stroke for a 454.
For building a 496 from a 454 block, then the 4.25in crank is used. If you are building the engine from scratch, and the cranks are the same price, I'd go with the 4.25in crank and build the 496. Trust me, you will LIKE IT! :thumbsup:

To get the 496, you have to use the 4.25 stroke crank AND have the block bored out .060, to a 4.31 bore, it is better to use the .25 longer piston rods also.

If I decided to stroke this 454 and I have to use the 4.250 crank, someone said you will have to go .60 over. Do you have to go .60 over to stroke it or can you go .30 or stay standard?

If I decided to stroke this 454 and I have to use the 4.250 crank, someone said you will have to go .60 over. Do you have to go .60 over to stroke it or can you go .30 or stay standard?

yu can go .030 NO PROBLEM ,this will make a 489 ! its just a difference in piston size .

Bored .060 makes it 496 stroker
Bored .030 makes it 489 stroker

Ditto.

pdq67