OK, I'm back and I hope ChevGene is close by.
The head on my engine has the following casting numbers;
GM
3835409
25

CONV12

E 59

I measured the bore in three cylinders (as best as I could) and came up 3.570", 3.569" and 3.570"

From what I have read 2nd generation bore sizes were;
216 CI - 3.5000"
235 CI - 3.5625'
261 CI - 3.7500"
The bore measurements point to it possibly being a 235 CI, can anyone tell me if the casting numbers indicate the engine displacement?
Thanks again.
Bill

There is no 3835409 head. There is a 3835499 head and it is for 1950-1952 235 engines.
This + your bore measurement indiactes it is a 235 egine. Just behind (to the rear of) the fuel pump there should be a raised circle about 2" in diameter with a 0 inside. That would indicate a 1950-1951 block casting. On the left side of the block , center lower, there will be a stamped plate attached with thrre screws. The oil distributor valve in under the plate. That indicates a dipper type engine.
There is also a block casting number on the lower right side of the block.

This could be a 235 engine from a large truck (solid lifters) or from a car (hydraulic lifters). Other than the cam and lifters the engines were the same.

Thanks Gene.
I have a picture of the head showing the 3835409 casting number, but I don't know how to send it. The 6th number is clearly a 0(zero) not a 9(nine).
Bill

I don't recall where I got this list of casting numbers, but head 3835409 is listed here for 1949. Tom

https://www.dropbox.com/s/a69qwoeaknwjam9/Chev%20engine%20casting%20numbers.pdf?dl=0

Yes, there was a 3835409 head. Made one year only for 1949 216 engines. In 1950 it was discontinued and the 1950 head took its place in prodction as well as for replacement going back to 1941.
If it is a 1949 block the circle to the rear of the fuel pump will have an 8 in the center.
The 216 block will have the push rod cover that is 9 1/2" tall where as the 1950 and up 235 would be 5 1/2"

Te 3835409 head was also used on the old style 235 for 1949 only.

Tom and Gene, thank you both for dogging this for me.Today I'll look for the number on the right side of the block and measure the push rod cover height. I'll post the results.
Bill

Here's what I found;
number on the block - 3835309
number on the head - 3835409
number in the circle - 48 (with a 10, followed by a raised triangle under it)
push rod cover length - 9 1/2"
left side 3 screw plate present
Per the chart provided by Headlighter, the block # indicates '48-'49 235 truck. The head # indicates '49 216 and 235.
looks like it's a 1949, 235 truck engine.
Thanks again for teaching me something.
Bill

The above would then be correc. A 235 engine that looks just like a 216. While it did not have as much power as the 1950 and up 235 it will have more low speed torque than a 216. and be of the same external demensions.

Again, I thank you for your help and consideration.
Bill