QUOTE(Dr Evil @ Apr 11 2011, 07:28 PM)
PRS914-6, do you heat the heads to 425* in an oven first? I have read that.
Thanks for the clarification about hone and ream. I am using phosphorbronze in my heads, which are aluminum. With luck, the steel valves will have good clearance, but just in case, I would rather be ready to do the work myself.
If I were replacing the seats, that would be a different story.
If you drill the guides out thin, they come out easy and no heat needed to remove.
To install I heat the heads but 425 is too hot in my opinion.
You can install the guides and have a shop hone them and cut the seats. That will at least save a few bucks.
When you drive the new guides in make a spacer to fit over the guide to prevent driving the guide in too far. The driver will hit the spacer and stop. It's hard to tell in this pic but you can see a metal spacer around the guide. The length is the factory spec for guide height
Also, don't use valve grind compound to lap the valves, that's a joke. The valves get hot, expand and don't ride in the exact spot anyway. If you cut the valves and seats properly they are both round and seat without any "help"
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