View Single Post
  #60  
Old 10-03-2023, 07:55 AM
PAUL K's Avatar
PAUL K PAUL K is offline
Ultimate Warrior
 
Join Date: Feb 2004
Location: Sugar Grove IL USA
Posts: 7,441
Default

Quote:
Originally Posted by mgarblik View Post
I had a little time to bolt a torque plate on the block and get some preliminary cylinder bore measurements. I will post up a bore chart in a couple days. It appears this block was torque plate honed in 1980-81 when it was rebuilt. I measured one side with the plate on and then measured the other side without the plate. The SD-455 block is extremely stiff, nothing like ANY Pontiac stock block I have ever measured. The difference between plate on vs plate off was no more than .0005" difference anywhere I measured thrust or pin side. A typical Pontiac block will be .001-.0015 variation, plate on vs off and some that are near .060" over size can be .002-.0025 variation. Very impressed with the casting quality and stiffness. When I get it home I will weigh it empty and compare it to a 72 455 I have laying around here. It will be interesting to see how much heavier the SD block is. I will make a guess that it is 15 lbs heavier than a regular 455. We will see.
Any chance you could Sonic scan of the cylinders?

Unfortunately the SD blocks I've checked the thickness isn't very impressive. I've only scanned about a half dozen or so and all have been 1974's or SR blocks. I'm curious if the earlier cast blocks may have been different .

__________________
Go fast, see Elvis!
www.facebook.com/PaulKnippensMuscleMotors