Probably only a few places really making valves any more.
When the "real" manufacturer runs out, all the labelers and re-packagers run out a little while later.
Been going through this lately on that same 1.65 exhaust when my normal supplier ran out.
Seemed everybody else was out of them too....
They are back in stock now at the supplier for what its worth.
Like other parts, the perceived suppliers and the true manufacturers are often different.
A lot of performance marketers are skirting or ignoring the whole "Country of Origin" label deal.
I think - but do not know anymore - that both Rev and Ferrea come out of Argentina.
SI stuff used to be from Israel, but I don't think that is true anymore???
Basso supplies a bunch of private label valves in different price & quality levels - Mexico, China, and ?
Eaton supplies a bunch of private label valves in different price & quality levels - South America, China and ?
Dandekar in India provides a ton of inexpensive valves but nobody admits to using them
A flat zillion valves are coming in from China but nobody admits to using them.
From what I can find there are no American made stainless valve suppliers of any scale/volume.
FWIW the valves I use in my heads are coming from Rev (or Ferrea on occasion), the cheap ones I've used in factory replacement heads come from PEP but are certainly Chinese in origin.
The cheaper stuff is obvious from the price point - just don't believe in all the "copy & paste" fairy dust metallurgy and engineering claims when purchasing a valve that costs 70% less than a brand name part. When you pay six bucks for a valve you are probably getting a six dollar valve. For many uses they are perfectly adequate.
