IcemanG17

Out of pure boredom I've been researching some common V8's bore spacing and deck height? I can't find anything on the 928's.....I heard the 928 has a bore spacing of 122.8mm but can't find it......which seems really good considering a small block chevy is 111.8.... So it really is a big block.... The biggest engine I found is a big block chevy with a 5" (127mm) bore spacing with a deck height of 11.625" (295.28mm)...damm that can make a HUGE engine!

If the chevy LS7 can run 104.9mm bores with only 111.8mm bore spacing (93.8%) then in theory a 928 could run 115mm bores??? Hmm 115 bore with standard stroker crank...nice 483ci 7.9L engine!!

Mike Simard

Oooh! I know this subject
The 928 has a 4.803(122mm) bore spacing and a 9.134 deck height.
It's the same bore spacing as a Mopar 426/440 and a deck height close to a small block Chevy, it's a 32 valve big block!
A Big block Chevy is 4.840. Most American big blocks are about the same bore spacing as a 928, small blocks are typically 1/2" less than that.
Yes, a 928 has plenty of room for big bores if sleeved. I have a 4.28 bore (108.7mm) and there's still enogh room left for the cylinder bodies to not touch. If only the 928 was a cast iron dry deck design, 4.5 bores!

BC

Wasn't there a mention of a place that does billet blocks custom?

Jim bailey - 928 International

Guy in San Diego has a custom big block chevy running 928 32 valve heads. He uses a special aftermarket block with the bore spacing adjusted to fit the heads.

mark kibort

something like this?

mk

IcemanG17

So couldn't a 928 V8 run the same bore-stroke as the LS7.....104.9mm bore & 101.6mm stroke to make a 7.0L 427? The deck height of the 928 is only 2mm less than the 350? Or even a 105.5mm bore-100mm stroke to make a 427?

What is the longest stroke 928 engine in current use? Or one that ran with decent reliablity? How was the standard stroker 95.25mm crank length determined? Why not longer.....the LS7 has a longer stroke and rev's to 7K+??

SwayBar

Sweet looking intake! I wonder how it performs?

IcemanG17

He was at Sharktoberfest a couple years ago......If I remember correctly it made HUGE low end torque.....something like 500ftlbs at 2500rpms......all of this in a lightweight hotrod!

123quattro

The main difference that lets the other engines run bigger bores for a given bore spacing is how the cylinders are siamesed together. That frees up a lot of room when you don't flow coolant all the way around a cylinder. To get a really big bore in a 928 block you would have to cast them all together and install them together as an assembly per bank. I would think there would be serious thermal expansion issues associated with that.

ceedee

whoa... lordy