Spica head-to-manifold studs

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In V8 #165 John Hertzman gives a very good answer to Bruce Giller's
question as to what to do about the missing intake studs on his
refurbished head.

To more than somewhat paraphrase: Wes Ingram (apparently Bruce's
mechanic / supplier) said he couldn't find 1.25 / 1.0 pitch studs.
Assuming Wes I. is Wes Ingram, this surprises me. Unless the proper
combination of the 1.25 pitch length combined with the 1.0 pitch length
were 'unobtainable". John replied correctly (would one expect
otherwise?) that these studs are quite common on Alfas ( and probably
other cars) but come in a plethora of lengths. John continued with the
suggestion of finding the closest required length and if it's a bit
long, then cut it down to fit.

Glad I read John's post before beginning mine. However, I will go ahead
and state my intended opinion which is to go ahead and get a bunch of
longish 1.25 bolts, thread them in (might want to cleaned up the threads
first with a tap) then cut to fit.

My thinking is that it's considerably more important to have the 1.25
threads in the aluminum head, than to have 1.0 pitch nuts retaining the
manifold.

I am purely speculating that Wes couldn't find the correct combination
of lengths as mentioned in the second paragraph. However, that doesn't
mean one shouldn't try. If one had a proper stud remover they could have
saved the old studs, cleaned them up, have them zinc plated ,and all
would have looked quite 'fresh'.

Along these lines, I have always failed (until now) to remove the lower
studs on the exhaust manifold studs before taking the head to my
machinist. They need to be removed when he mills / skims the head (at
least on his machine). Generally the head comes back with the studs on,
but loose. Sometimes the head comes back with all lower studs missing.
Therefore I keep a few of those particular studs in stock. I've vowed
that from now on I'll remember to remove them before dropping off the
head.

As usual, making a long story longer, I recently had to replace four of
the studs on the Giulietta Spider's (the one I'm restoring for a client)
external trunk hinges. Even though I made a big fuss about having the
chrome shop wrap all studs, they still came back either badly acid
etched or with globs of chrome on themmaking it impossible to either
get a nut on or else I could slide the (correct) 5 mm nut from top to
bottom with virtually no interference.

There is a lot of pressure on these rather fragile solid brass hinges
and especially the end stud on the trunk side when the lid is held open
with its support rod. Unfortunately the only pitch that I know of
available for the 5 mm is 8.0 (I'll be standing by for your comments
John). Therefore, I cut off, drilled out, and tapped as deep as possible
the two trunk side studs on the hinges. Since the hinges were recently
chromed, I erred on the 'don't go too deep and through' side.
Consequently, I was only able to get three full threads on the end studs
and this was after grinding down the pointed end of a spare 5 x 0.8 tap
so I could thread as deep as I dared.

To further horrify all professional machinists out there, I put a good
dollop of JB Weld in each hole and of course let sit overnight before
installing.

I strongly doubt if the other two studs will ever pull out since I could
get around seven or eight threads on each.

In retrospect, I should have bitten the bullet and used the closest SAE
coarse thread. Still, I would have only been able to tap two or so
threads for the end studs.

Pretty exciting, eh? I include this all only in case someone else needs
to go through this rather painful experience or has a better solution to
chrome shop screwed up studs.

Biba
Irwindale, CA USA

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