Andrew,
I went with a Pierce Manifold head, non-crossflow. I bought it from
Pierce in Gilroy, CA. He manufactures them and sells them to Moss,
Victoria British, and other parts distributors. They can be
identified by the marking "PM 1" on the casting near the thermostat
outlet. The Northwest price seems comparable for a fully assembled
head.
The day I called Pierce, they had just sold out of the early heads,
and didn't expect the next batch of castings for a couple of weeks,
so I bought a slightly used smog head (4 hours of dyno time) for
$550. I ended up putting an additional $60 into manifold stud
helicoils, as a couple of studs pulled out during installation. I
paid someone to do that, though I could have bought a kit and done it
myself.
In a related note, Carrol Smith, race car engineering guru, says in
his book on fasteners that anything that needs to be removed and
reinstalled regularly on an aluminum casting should have some sort of
thread insert installed. I'm thinking that I will put in Helicoils
for the spark plug holes the next time the head comes off. I had an
interesting experience this weekend with my newly purchased Gunson
Colortune glass sparkplug that makes me think this is a good idea.
With the engine warmed up, I tried to install the plug, and it felt
like it was cross treading, or at least distorting the threads.
Wouldn't go with finger pressure--I tried nudging it with a wrench
and stopped before doing something I would regret. Nothing wrong
with the plug--it threaded in nicely to an iron head sparkplug hole.
Perhaps a matter of tolerances or expansion of the aluminum. I could
pull the head and retap the hole, but I'm worried about stripping out
the threads, so an insert seems prudent.
The head I bought has the smaller of the two stock sizes of intake
valve (since they have to be smog-legal stock, and most engines they
are installed in don't have valve pockets cut in the block to avoid
interference), and some serviceable, slightly bulleted bronze valve
guides. One advantage of buying a bare head might be that you could
modify it for better performance without throwing a lot of stuff
away. If I had a little more time and money, I would probably have
gone this route, and used the best bronze valve guides I could find,
modified the combustion chamber to eliminate shrouding, and installed
larger flat-backed anti-reversion valves (Rimflo) and seats, and
perhaps a 3 angle valve grind. This would also mean cc'ing the
combustion chamber and skimming to achieve the correct compression
ratio. Lotta work--maybe next time. At least I wouldn't be worried
that the head could crack after putting all this work into it...
Andrew wrote:
>So I just learned what the coolant leaking above my # 2 spark plug
>is....
>
>What head did you go with? I found that Northwest has a:ALUMINUM
>PERFORMANCE CYL. HEAD,COMPLETE for $695. I am doing the finance review
>parts search now...
Chris Attias
'64 MGB
'84 Alfa Romeo GTV-6
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