at what point are inconel exhaust valves necessary?
 

just tearing into my xmas present to myself. tired gen 6 L29. was shopping for heads for my mk IV and found a complete roller gen 6 instead. i am looking at under 450hp, over 112 lsa, under 5000 rpm engine use. and i don't even see inconels anywhere in 1.72 in. if an engine like this can live without, what is the second best choice?

competition 6000 stainless from Ferrea.,or something similar.

That engine should already have inconel exhaust valves. This is a replacement valve for that engine

http://www.race-mart.com/Sealed_Power-SLP-V2450X.html

http://www.napaonline.com/Catalog/Ca...50X_0204239889

It is a propane gas engine. 10 or 12 quart pan with multiple outlets on the side of pan like it was set up to change oil while running. I think some kind of industrial pump or something.

You sure its not a L21? Those had forged cranks in them.

don't have the pan off yet. good possibility. the ex valve; magnet has no attraction until the very top maybe 1/4 inch of stem. like they used a malleable steel for the wear point at the rocker tip. you can see the change in color above the valve lock where the material changed.

I believe the valves will be stellite and sodium filled.I remember using those valves from SBI.So thats why you see a cap like tip.

Yes I think stellite material. Stellite is also a material used on the faces of some flat tappet lifters

10114188 cast crank. oh well...got a 4-bolt roller engine for a nickel.

Must use inconel valves with a zz502 cam if you want to retain the oem cast iron exhaust lol jk its late .i mean early .but really the inconel and super duty valves seem to resist losing thier heads much better if something goes ugly with the exhaust water .