littledcsrodshop

iTrader: (1)

This may be a stupid question to some but is there any way to tell if a set of heads have inconel exhaust valves in them ??
or is there no real way to tell ?

Crazyhorse

Most valve manufacturers identify their valves with stamped or laser-etched numbers. You'd probably need to have the heads disassembled to see them though.
If in doubt I just buy new ones. They don't cost that much , especially as opposed to buying a complete engine if it comes apart by itself.

littledcsrodshop

iTrader: (1)

I agree it is definatly not worth taking the chance for less than
$200.00 . I was just kind of curious. I will pull one of the exhaust valves out & check for any markings. The motor had twin turbo chargers on it when I bought it. I would think that it would have had them in it. Anybody know when they started using inconel ?

Corbs

Just had a new engine built with Inconnel exhaust valves. My engine builder showed me where a magnet won't stick to the head of the valve, but will stick to the stem. I believe they were somewhere around $40 a piece.

littledcsrodshop

iTrader: (1)

That is interesting I will check into that.

mrhorsepower1

Bingo!

littledcsrodshop

iTrader: (1)

Can anyone confirm the magnet test on the valves as beeing that it will not stick to the head of an inconel valve but will stick to the stem ??? Reason beeing that I stuck a good magnet to both my intake & exhaust valve today & it stuck to the stem but not to the head of the valve I hope that is the ticket to telling because that would mean they are both inconel. Thanks guys.

Zanie

Magnet tests won't help you figure wether stainless or inconel.
A magnet will not stick to most grades of stainless 304, 316 etc.
a magnet will stick to 409 stainless, but I've only seen 409 stainless in tubing.
DS

kennyo

I may be wrong but "inconel" is just a patented name for a certain type stainless.

bcarpman

The term "Stainless Steel" is pretty generic and simply means steel that won't corrode under normal conditions. Inconel would technicaly be a stainless steel. I think inconel is a trademarked name and has a couple other additives other than nickel and chromium which are common in ordinary stainless.

Inconel does have significantly better high temp properties than ordinary stainless. I think some manufacturers may use non-trademarketed materials that are very similar to inconel in their extreme duty valves. I think Manley's are that way.

Most stainless is not magnetic, but some are. It depends on the nickel content. If the nickel content is high enough, the valve will pull slightly on a magnet. Some stainless intakes are this way. It's not a bad thing, as intake valves don't undergo the extreme temps that exhaust valves do, and require different properties at different temps.

Oh yeah, and a set of Inconel valves will set you back a lot more than $200. More like $320