The stroke takes into account the throw on the crank, not the piston pin location.
Because of the long stroke of the 454 GM had to put the balancing weights external to the oil pan. A 454 has it's own Harmonic Balancer (known by many names) and flex-plate/flywheel. Other than that the two motors look much the same.
Vern

 

Vern, if both block has 9.800 deck height with both of them using 6.135 rod ........something got to be different right? I am missing something here but do not know what???? is piston to deck the same for both motors??

 

all car big block's have the smae deck height(the truck big block is know as a tall deck)but the 454 and 427 have the same bore..which you already know that....the same rods...the locaction of the piston pin is different....the balancer's and flywheel are also balanced different....the big block much like the small block are all the same on the outside...if some one say's that they have a 396 ..it may be a 555 or a 540 cause the dimintion;s are the same....my friend has a 9.40 second nova..with a big block ...he say's it's a 402..to get people to race...but it's really a 540ci.....

 

454s-10 is right on the money. One of the formulas for Cubic inches is (Bore X Stroke X # of Cyl X 3.14159). Stroke is the distance the piston moves up and down in the cylinder. Changing the piston Pin Height won't change the stroke. Changing the Piston Pin Height will have an affect on compression. There are different rod lengths available too. This will have an affect on the dwell time the piston spends at TDC and the speed at witch the piston moves. The cubic inches really involves the area from TDC to BDC. Hope this helps, someone else may have a better way of explaining this, if so please jump in.
Good Luck,
Vern

 

I think ,simply put, that you are correct, the pin height is different to allow for the longer stroke. That's what 454s10 was pretty much stating and I think Vern is still missing.

 

Are you worried about the block...
Because that is different as well!!!!
You must clearance grind a 427 block to fit the 454 crank into it.
The crank throws hit the bottom of the jugs!

 

Thank you for clearing this up for me ......now I understand the diffrence between the two.
Luc.

 

Still missing???Let me check... yes, I thought I agreed with everything 454 S-10 stated. Woodz428 if you will read camaro's second post... He is still confused as to how the extra cubic inches are made. Remember that the area above the piston doesn't add cubic inches. I don't know maybe on a Ford it's different?

 

Hey Vern I know were the cube are from I just wanted to know what are the differences besides the bore and strokes.

Don't worrie probably my post was not clear enough :thumbup:

Luc

 

As I read his post and he re-stated. He wondered how the extra stroke worked in the engine if it used the same rod, and surmised,correctly, that it was in the location of the pin. You had read it as him thinking that the extra inches was from the pin height, but he indicated the differences in the stroke in his post.

 

Thanks woodz... I did read it differently.