One component set of the engine build that I am planning is over sized intake and exhaust valves. The question I have is on valve seat hardening. The machine shop that I have quoting the work listed "flame hardened" exhaust valve seats at $75.00 for the set. They say that the intake seats will have acceptable durability with out hardening. My build is a mildly warm street motor, looking for a soild durability / low fuss over many many miles. Are other folks going the flame hardened route, or would I really want stellite or other hardened seats? Just exhaust or intake and exhaust.
95% sure that I will use a hydraulic valve train.

thanks

"Flame hardened"...? Pfft. No. A proper head rebuild includes hard, high-grade-alloy exhaust valve seat rings installed in the head machined to accept them, then the seats themselves machined (ground) on multiple angles to blend the new seat rings into the head casting so as not to restrict exhaust flow. New exhaust valves, too. The shop's right that the intakes don't need hard seats.

Good source for valves is engnbldr.

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Too many people who were born on third base actually believe they've hit a triple.

I will bet "flame hardened is a misnomer. If you talk to your machinist he will probably describe the process Dan is talking about. DadTruck if you want to look at Enginebuilder's valves up close and personal, come on over, I just received mine in the post.

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66 Lil' Red Piggie Valiant (Mater Crusher) - Thanks Zilla!!!!! 72 Demon (Number 1 Son's)

Do machine shops "Grind" valves and seats anymore?
I was under the impression that they mainly machine cut them now.

CJ

Some do here in the Salem area, but you have to be in the know which old timer to talk to... I have heard there is a place that still does this method and does porting services... I'm thinking I've got to up the ante to find out who that one is in my area...

I have Hpak duster's head in for reconditioning, given that the original induction hardened seats are not looking all that great and am dropping in a set of stainless valves, I am opting to have stainless exhaust seats put in this time... This is a test for a machine shop I've never used, but have heard good things about it...if this works well, then the K-B pistons will go in for fly cutting next...

-d.Idiot