11 Stud Block

[prop]

I have just finished drilling my block to make it 11 stud.
The general opinion seems to be that 11 studs reduce gasket failure.
The head I have from MED is 11 stud so I thought I would drill the block.
I have a small pillar drill and the block just fitted under the chuck with a shortened 5/16th drill. I marked the block using the head as a guide. I suppose using the gasket would have worked as well.
I made sure the block was positioned correctly (90 degrees to the drill) and then I drilled straight in with the 5/16th drill.
Cast iron is easy to cut. The thread cut easy. Everything went very well and the head fits perfectly
Water pump end stud is only torqued to 20-25ftlb

[prop]

Two more photos

[G96LUE]

Looking good.
I have never had a gasket failure at the ends of the head myself though.
Mine always seem to go between 2&3 on the narrow bit.
I have never understood why the cylinders are not equally spaced making the material between 2 & 3 slightly wider.
I'm sure there is a good reason though.

[paul]

Thought it was a smaller diameter bolt nut a head stud there?

1275's go between 2 and 3 998's go 1/2 or 3/4

[prop]

The ARP 11 stud kit comes with all studs 3/8". It is only the early Cooper S engines that used the smaller 1/4" stud at the end. It actually used a bolt. A 1/4" size if desired for a concourse restoration but for a performance engine 3/8" is not a problem.
I know 11 stud on the ERA is not original. The main reason is I had the head with 11 stud holes and I didn't want it to be on the car with a hole at either end so I decided to put a bolt in them. As this is not detrimental to the engine and possibly a benefit I thought, why not.