I can't seem to find out who the manufacturer is or find another set that has all the same features.
Cast Iron
3/8 Screw in Studs/guideplates
2.02/1.60 Valves
Center or Perimeter Bolt Valve Covers
Vortec Intake Pattern
No Casting Numbers on them. There is a stamp that says THS or THSC
They have heat tabs on them that say "Warranty Void if Removed THS"

Here are some pictures.
http://s161.photobucket.com/albums/t226/ChadNickel/
and for some reason my wifes dog likes to sniff them don't know if that will help or not.

I don't know. I haven't seen any like that either. They would almost have to have a # on them somewhere. At any rate. They look like a pretty nice head. Wanting to sell them?? Johnny

After having a second look. Two things. First. I see some kinda stamp below the heat tab. And second.Why are there no bolt holes for the center intake bolts? I couldn't see them sealing too well with just the outer bolts sealing the intake ports??? Johnny

Vortec Style intakes only have 8 intake bolts, I don't know why but thats the way they are. The stamp below the heat tab says THS. Here is a pic of a Vortec Style intake for those that have not seen one. Notice the intake bolts. http://static.summitracing.com/global/images/prod/large/edl-2913.jpg
I just bought them for $500 and I am trying to decide if I got a good deal or not.

Try looking Hotrodsusa heads over b/c they just may be those kind??

http://www.hotrodsusa.com/

And I figure they are good value, especially their aluminum jobbers...

NOT race heads, but still darn good street heads to me..

pdq67