Don Terrill’s Speed-Talk

mag2555 wrote: ↑Thu Nov 29, 2018 7:43 am Is there is no Groove for a o ring seal so it's really not a stock replacement it would seem!
It is a 2 peice valve though and you want stay far away from those !

How do you know it's a 2 piece valve? From the pic you can see the hard tip, but that color change about an inch from the tip is where the valve is either running in guide or seal and got polished. On 2 piece valves the joint is down at the other end of the stem more, usually just a bit into bottom of guide travel. Has anyone actually seen a 2 piece valve ever break on joint? I haven't.

I am with Bill-C on this one. I see a hardened tip on this valve which needs to be there and is on most stainless valves. If you check out how two piece valve stems are put together, it is not some simple glue together process and I also think I have not seen any high performance two piece valve stem valves, or any failed valves that are a result of two piece stem failure.
I am sure back in history a few were tried and probably were not very successful and hence faded away into the sunset!

A few years ago I was at CV products for a 3 day long spintron session and got a tour of the Xceldyne plant next door where they make their valves. The ti valves are all at least 2 piece ( wear resistant material for stem, heat resistant head). Their fanciest valves were 3 piece hollow stem and hollow head.I didn’t get a chance to see any steel valves being made, but learned a lot about the manufacture of ti valves.

I've also seen Melling number their valves in this manner, V****


For example, V5126 is a Melling intake valve.

https://www.oreillyauto.com/detail/b/me ... 26/4441832