You can take a stock block more than .030. I've had two that were .100 over with no problems. You can go as much as .125 over but i would get it sonic tested first. A .100 over with a 4.25 stroke is a 505 a .125 over with a 4.25 stroke is 511. Just some ideas.

you are right, back in the day, that was what we called a big cube motor. :)

I was trying to think outside the box. If a person wanted to use the stock block,and money and time invested in clearancing weren't an issue, what kind of crazy sh#t could a person accomplish. How about a 4.375" I've always heard only 4.250" also, but I wanted to see if anyone has pushed the envelope.

talking about stock appearance Big Cube engines...how about a small block appearance with close to 500ci........

Now if ya got the money and ya wanting to play some mind games..go this route...i will argue with you all day long is a 355ci.... 8)


i ran a .125 454 block with 4.25 stroke..ran like a scalded dog..it was not hardblocked and i had zero Problems..i broke a lifter to end this engines life.

i personally would keep it at .100 over with a 4.25 stroke

I personally donot like sleeves in a steel block, either sm/blk or b/blk, they almost always have a head gasket sealing problem. I would rather change blocks than to sleeve one.

JMO

Zip.

I have a 4.5 stroke in a stock GM block. Made 900 hp on alcohol. There is some grinding invovled but then again your saving 2500.00. I personally think the purchase of a Dart block is money well spent. If you do decide to go with a stock GM block use a tall deck. That way you can use a longer rod. 4.5 stroke 4.375 bore is a 540. My block has no sleeves. I did fill the block with cement though. Ill probably go to a Dart block next year and 4.625 bore. One other small gain to a GM block is I think there about 100lb lighter than a Dart block.

4.5 crank
 

Yes you can fit a 4.5 stroke in a stock 454 block . I have done it wit an eagle crank , eaggle h-beam rods and cutom J&E pistons . It was not easy . I had to machine to O.D. of the counter weights off the crankshaft which required a lot of extra work on the balancer and plenty of heavy metal . The pistons have a 1.145 compression height . The end result was a 518 cubic inch BBC for a motorhome . Massive torque output . i am now putting that same engine on an airboat .

Just my experience, but I have a 496 (4.310 bore x 4.250 stroke) with aluminum rods and a 511 bbc (4.375 bore x 4.250 stroke) so far no problems with either combo.