MikeyZ

iTrader: (20)

im looking at a set of rebuilt 806 heads for 150 and the machine shop ground the valves for a three valve job but my local shop said you can grind valves is this accurate?

BlackScreaminMachine

iTrader: (17)

I am not a machinist but lets just say the only "grinding" is at most for me would be valve lapping. Which can be a DIY'er.

If you can, explain a little more.

Abuckeye

That's how they use to do it in the old days. I think they used a fixture to hold the valve next to the grinder to get the correct angle. So I'm told.

JRENIGAR

iTrader: (37)

yes... you regrind the angles on the valves to match the angles grinded on the vlave seats in the heads. Most commonly referred to as "3 angle valve job". Supposed to help with air flow also. Unless you have the machines to do this then no, but valve laping can be a diy job.

NVR_SPDS

iTrader: (39)

Valve lapping is done by hand. You can an abrasive paste, and apply it to the valve seal area, drop the valve in, and spin it on the seat. This will improve the seal.

Grinding the valve requires a dedicated valve grinder. I use a Souix grinder at work for valves.