I got a set of DV's in a trade and can't figure out what size they are. The valve looks like it could be a 191:

but the holder, or barrel (I think it's called) looks different. Every 191 holder I've seen looks like this:

with the little lip/ridge at the bottom. But these look like they've been machined more, what would be the reason to machining that lip/ridge off? I thought fuel was only meant to flow through the center of the holder that the valve sits in?

Also in two of them, or four, the valves are upside down in the holder and since I can't indentify the top from the bottom I don't know which ones are upside down. I *think* the two on the far right are correct and the left side four are upside down, but it would be nice to get others input. Thanks everyone

 

Those are 181 holders, what are the numbers on the top of the delevery valve itself? There should be 6 numbers. Also the machined lip goes down.

Jim