[afterburn 549]

Thanx
I am limited to the machine work I can do-
I do all my own valve work-started when an old guy said to a very your man "go over there and just do it"
Nowadays I think I have become a bit of an expert...
SO many things to learn and hard to dwn load to another person.

For instance, it goes against all rule of laws to move the seat to the top of the valve.
I will guarantee you some very great results in performance if you do only that, and make them NARROW!

As you said there is a trade-off

I build all my own heads for 20K mile turn around. With almost all high-performance stuff it just doe not last as long.
My last top-end ended when the pinion nut did not hold the drive gear. Thankfully I had just got back from Sturgis ( I refuse to trailer as that is for the poser crowd)

What did I learn and no one ever told me? ( and no one will say to this day anywhere)

The pinion on an EVO is the weak link-
It is not tapered shaft like the shovel, (and that is a BIG deal)
It is just around shaft.
It has about a fingernail thickness of a part of a 1/2 moon holding the drive . (not enough)
All is well until a person installs a large bump stick and HIPO springs -the continual rocking back and forth at low RPM will make that skinny little nut lose its grip, and then?
The exhaust valves will kiss the pistons ..just a little.

After much constipation on NOT ever wanting that to happen again, I installed the new nut (read tiny thin anemic ) to the prescribed 40-foot lbs I think they call for with a quart of the red Loctite .
i still did not think that was gooder enough, and tigged a spot 180 deg from each other . It can al be ground off in a minute when the time comes..
But i gaurantee me it is not going anywhere this time.!