Another thing to look at is the rocker assembly. The last head I did
for my car I took a close look at the rocker tips and did not like what
I found, they were all worn and there was no way the valve adjustment
could have been right. The feeler gauge would bridge the wear and the
gap was off. I think this is what lead to my constant valve adjustment
problems. I ended up with a couple of sunk valves which I think was
caused by the loose adjust from the worn rockers and it just beat the
seats down. I went through my pile of rockers and picked the best set.
Then when I looked at the rocker shafts they were badly worn also, I put
the best shafts I had in but still think a new set is in order. I went
through parts from a half dozen or so heads to come up with the best
bits so I think this is a wear issue that most cars have and is over looked.
I built a Datsun valve head for my big motor and it cost big money,
parts and labor over $700 with stock Datsun valves, Crane springs and
retainers. The parts are not all that costly but the machine work to get
them in the head is. Jim
Jarrid what are bronze guides are you using, are they off the shelf?
Jarrid Gross wrote:
>Eric,
>
>Your machine shop is right, unleaded has nothing to do with the bent
>valve.
>What did? The fact it was en exhaust valve tells a story in itself.
>Perhaps lack of proper adjustment, burned the valve, then it stuck
>and got struck by the piston?
>Or perhaps you overreved the engine and bent a valve.
>
>
>On valve size, forget what the girls tell you, size DOES matter.
>The question is, how much coin you got floating round in your pocket?
>You wont be able to open the valves up to a considerable improvement
>without spending some serious money.
>
>On titanium, get out cubic coin here.
>
>On grind, a nice 3 angle valve job is nice.
>Wont make a big improvement, but is an inexpensive way to get another
>pony.
>
>New guides are reccomended as are new valves.
>Upgrading to guide seals is fine, but only if the guides are silicon
>bronze, not the cast iron originals.
>
>Thats all I can think of for now.
>Good luck
>
>Jarrid Gross
>
>
>SerIIAlpine@netscape.net wrote:
>
>>Having bent the #1 exhaust valve on my 3000mile young engine I was wondering
>>what my options are regarding upgrading my head. I've already portmatched
>and cleaned up my head as per serII special tuning guide recommendations and I
>just wanted to know what I could do to make the head better and more durable.
>ie:larger valves(titanium?), what type of grind, what type of guides to insist
>on etc.
>>
>>I beleive the valve failure(It's stuck halfway down) may have been due to
>using unleaded even though the machine shop that did the head said it wasn't
>an issue.
>>
>>As always, thanks for any and all help.
>>
>>Eric
>>'62 serr II
>>
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