Notched 068 block

[Gliderider06]

Question. I thought that the 068 blocks were passenger car engines? I have one that has notches in it. Did they also use them for trucks as well? The front pad has no stampings on it. This is the block that I am going to eventually build for my 63 and was curious about it having notches.
Thanks!

 

[MRHP]

Yup, truck block. Casting number used for both. Blocks are identical except for the notch.

 

[Murphdog]

Same casting/block, just machined differently. I have an 068 notched/truck block.
Jeff

 

[awsumcars]

Ok, Single notch truck block. What are the truck blocks that have double notches? Also, one chart on the forum shows the '65 truck 348 & 409 are built stronger (thinking more nickel) for heavy duty use. Are these blocks then theoretically stronger to build?

 

[Don Jacks]

Most of the double notch blocks were 5011 castings.The 62 962 as well as the 655[ blocks with the ''x''] on them were the strongest.

 

[Murphdog]

As far as I know a 409 truck block had single notch cylinders & 348 truck had double notch cylinders. Don't think the "higher nickel" thing has ever held water. Just a fantasy. 65 blocks being any "heavier" blocks ?????????????
Jeff

 

[61BUBBLE348]

655 348 truck block has a single notch

 

[oldskydog]

Double notched blocks went away after the 333 heads came out in 62. they had a combustion chamber in the head so second notch wasn't needed.

 

[427John]

Early truck 348 blocks were double notch, later truck 348's were single notch, I think they coincided with early 348 truck heads not having the combustion chambers like the later 333 truck heads.

 

[MRHP]

The 409 never came with 2 notches.

 

[La Hot Rods]

Your right, it came with 8

 

[quik9r]

Jack Gibbs really liked the 068 truck blocks, cant remember the reason??, but he purchased the one I had at the time

 

[Gliderider06]

I remember Curt Harvey saying that he liked the notched blocks because they unshrowded the exhaust valve, similar to bolting on a set of headers.

 

[quik9r]

I remember Curt Harvey saying that he liked the notched blocks because they unshrowded the exhaust valve, similar to bolting on a set of headers.

yes Curt Harvey did a say that as do others. Gibbs was specific about the 068 truck block, cant remember at the moment

 

[Ishiftem]

There is no benefit to the exhaust notch. I tested it. Sure, it looks like a benefit having all that extra space around the valve. However, the flow of gases is not intuitive.

 

[DaveN]

I bought a 068 block earlier this year. It was a boat block and had the notches in it.

 

[buildit]

All W-motor blocks with the "X" on the front have heavier main webs than earlier blocks. They also have Armasteel caps, whether that means anything, I don't know.
I also believe they are higher nickel content. I can't prove it, but it's just my observation after machining blocks for several years.