I think you will find also that standing the valve up allows for a smaller combustion chamber, therefore higher compression with less piston dome.

Bill

how do I know what dash 12 heads specs.one has .# on the end ? please

I have a set of Brodix -12 heads that were ported by Weldtech. I wanted to know about the heads. I got ahold of both companies and gave them the numbers stamped into the heads and they told me everything I could ever ask about and more. They were great.

If you go to Brodix website, you can enter serial number for the head and the will tell you casting date and the head type.
http://brodix.com/serial-number-identification

Thanks. I actually found a perfect diagram of that on the Net, tried to post it, but can't for some reason... "copyright" was mentioned
Since we're on "Dummies Guide to Sprint Car Engines", I have another question that I asked a few years ago & didn't really get the answers: Down nozzles: Do they carry pure fuel, or fuel air mix? If its pure fuel, doesn't that alter fuel/air mix? Do they compensate by running the injectors leaner?

Nozzles lines up or down are just fuel, the nozzles has an air gap to prevent sfioning, that is were fuel atomization occurs.

A engine can have up or down nozzles or both. Until the fuel reaches the nozzle it's 100% fuel. The nozzles are vented which allows the fuel to draw in air.

Thanks, Motorhead!

Thanks Tony.... I won't even make fun of your spelling

"syphoning"

Some guys can spell, others can build engines. Wish I could do both!