Bore spacing & deck height ???
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From: Stockton, CA
Bore spacing & deck height ???
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!!
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!!
Three Wheelin'
Joined: Aug 2006
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From: Atlanta
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!
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!
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From: Anaheim California
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.
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From: saratoga, ca
something like this?
mk
mk
Originally Posted by 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.
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Joined: Sep 2004
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From: Stockton, CA
Originally Posted by 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!
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!
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+??
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From: Stockton, CA
Originally Posted by SwayBar
Sweet looking intake! I wonder how it performs?
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Drifting
Joined: Nov 2006
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From: Farmington Hills, MI
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.
