Hi Guys,

I just bought a 14093638 4 bolt block and I'm having some trouble with the information I've found concerning the block.

From what I can tell there were a few versions of the block, both 2 and 4 bolt, and roller and non roller, which s confusing enough, but apparently all 638 blocks are set up for roller cam, they just don't have the bolt holes tapered, is that correct?

There lifter valley has a couple of bumps in it so I'm assuming these just need to be drilled and tapered for the lifter spider to be installed, same with the cam section?

And lastly, would that mean it would require a OEM roller CAM type, or retrofit cam type when purchasing a new cam?

 

That block was a gen. use 350 block used in '87 to '95 for cars and trucks.

The cars would have this block setup as a roller cam, where the trucks would not. The provisions are made into the block for roller setup, just not drilled/tapped/installed on the truck engines.

Yes you can drill and tap it, then use a factory style/type roller cam.. You will need the stock roller cam spider, dog bones, thrust plate and lifters though.

 

Cool thanks.
I just was wondering how the same block could take the flat tappet and oem roller because I thought there was a difference in the front of the cam that would affect it.

 

You are sorta right.

The roller blocks will have a machined area and bolt holes for the thrust plate behind the upper timing gear.

Your block will have these places, but again may or may not be drilled and tapped.

That's the only diff really.. Just a place to bolt the cam thrust plate that holds a roller cam into the block. Both type cams will slide in. Flat tappet you just don't use the thrust plate, roller cam you do.

The roller cam it's self is "necked" down on the end to fit the thrust plate.