small block measurements ?
Thread Starter
|
I'll have the Roast Duck
Joined: Jul 2002
Posts: 9,622
Likes: 110
From: Northshore, MN
small block measurements ?
Does anyone have measurements between motor mount bolt holes on the block? I have measured 14 1/8" between them, but want to verify if this is correct or not.
Cargo Master
Joined: May 2007
Posts: 2,071
Likes: 36
From: British Columbia
Bolt spacing
Last summer I figured this all out since I welded up a wheeled "engine cradle" for a spare engine. Unfortunately I can't find the spec. that I determined, but I did make an important observation. This is that the mounting holes aren't exactly across from each other, one side is offset an inch more forward. Looking down from above the top of the engine, the holes on the right are more forward. This is for the engines with 7" bolt hole spacing, which is almost all of them. 1962 and possibly 1963 small blocks have 6" bolt hole spacing, so might not be longitudinally offset.
Cargo Master
Joined: May 2007
Posts: 2,071
Likes: 36
From: British Columbia
Engine mount spacing
I dug through the clutter to find my spare 260 bare block tonight to find out what this dimension really is. Without an oilpan installed, I could screw in a head bolt in each motor mount hole, and insure the bolts weren't noticeably bent as they screw in. The bolts stick out enough so a direct measurement can be made across their heads. I did this while pushing the bolts outward and then pushing them inward so I could average the dimensional variation caused by the bolts rocking in the holes.
The value I came up with is 13-7/8", with an error of +/-1/16" at most. This is also taking into account of one bolt being an inch ahead of the other. In other words, 13-7/8" +/-1/16" is the dimension between the mounting bolt holes if they were exactly across from each other.
The value I came up with is 13-7/8", with an error of +/-1/16" at most. This is also taking into account of one bolt being an inch ahead of the other. In other words, 13-7/8" +/-1/16" is the dimension between the mounting bolt holes if they were exactly across from each other.
Thread Starter
|
I'll have the Roast Duck
Joined: Jul 2002
Posts: 9,622
Likes: 110
From: Northshore, MN
And here we are back again. One more measurement.... With the 7" distance between the block bosses, and they being offset forward/backward 1 inch from each other, and since the mounts are interchangeable side to side, I'm assuming the mount-bolt to perch is offset 1/2" so that they drop into the perch evenly. In other words, the perch holes are the same forward/backward distance to each other. (14" from the bellhousing surface)
Let's say, 7" long, 3.5" being the center, offset 1/2" would be 4" and 3", flip flop them they would be 3" and 4" on the other side, but with the 1" block offset, they would still be 3" or 4" right? SO the P side would be 4" from the front bolt on block, and the D-side would be 3" from the front bolt on block.
Let's say, 7" long, 3.5" being the center, offset 1/2" would be 4" and 3", flip flop them they would be 3" and 4" on the other side, but with the 1" block offset, they would still be 3" or 4" right? SO the P side would be 4" from the front bolt on block, and the D-side would be 3" from the front bolt on block.
Thread
Thread Starter
Forum
Replies
Last Post
FuzzFace2
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
14
Oct 31, 2017 12:25 PM
UNTAMND
1987 - 1996 F150 & Larger F-Series Trucks
18
Aug 13, 2016 06:12 AM
tabascom16
1973 - 1979 F-100 & Larger F-Series Trucks
2
Aug 29, 2015 02:36 PM
