Never use an anti seize that contains copper in it on aluminium heads. The copper will react with the aluminium creating electrolysis and will eat away at the heads.

the conventional hex head takes a 9/16 socket and the equivalent ARP takes 3/8 socket.
I have found that 1/2 drive sockets are too bulky for the centre bolt. Standard hex bolt with 3/8 drive 9/16 socket works.
I think hex socket head bolts would work but you would have to have a good washer under the head as there is not much under head area. Also most socket heads I've seen have a generous under head radius requiring a matching washer.
Interesting re the Never-seez, I do not have any but I do have several tins of Copper slip, some a lot stiffer than others, which I hear was designed for furnace door hinges
stuey

Never-Seez won’t form a gasket in the true sense of the word, Darrell. It will fill S-M-A-L-L gaps. The exhaust manifold flange surfaces need to be basically true. As you indicated, it never really hardens,but in my experience does become more paste-like over time due to heat exposure drying out the liquid ‘carrier’.

I use a prudent amount of Never-Seez on exhaust manifold to cylinder head mounting bolts. I use a more generous amount of Never-Seez on the exhaust manifold stud threads that secure the exhaust head pipe to the manifold. While Ford used brass nuts in production assembly for securing the head pipes to the exhaust manifolds to try to make them easier to remove when necessary, when the steel studs rust and become corroded as they do with time, the brass nuts are still miserable to remove if Never-Seez wasn’t used during the exhaust pipe installation.

With JM’s aluminum heads, I recall Ted writing a caution regarding using Never-Seez on spark plug threads. My take-away understanding from the posting was, ‘Coat the spark plug thread surface; DON’T fill the threads. Excess Never-Seez can ‘crystallize’ or cake-up (my words) on the end of the plug exposed in the combustion chamber and make removal of the plug difficult’.

______________________

A friend uses Molybdenum disulfide grease instead of Never-Seez when mounting cast iron exhaust manifolds on y-blocks. Molybdenum disulfide is silvery-black in appearance. In both looks and feel, Molybdenum disulfide is similar to graphite.

At one time, Molybdenum disulfide was the lubricant supplied with many new camshafts as THE assembly /break-in lubricant. I don’t know what is in some of the camshaft installation lubes being sold today.

NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York

I would never have guessed never seize would have formed a gasket. I was wondering about using it on exhaust manifold bolts as well. Knowing the way it stays in the threads and how it never seems to become "stable" I would have assumed it would just make a gooey mess. If it worked for you its probably worth a try.

Darrell Howard Whitefish, MT Outlaw 56 Ford F-100's

Re: gaskets. I shouldn't doubt the experts here, but the A&P mechanic in me made me check the book. It says to "coat the mating surfaces with graphite grease." If high temp RTV is what you guys recommend, well, them exhaust manifold gaskets are going in the feces can.



Now where did I put that high temp..................

Stuey, what is a small head ARP bolt? Anyone have any opinion on the round headed bolts with the hex head in the center? Is anti seize on exhaust manifold bolt threads a bad idea because of the heat?

Darrell Howard Whitefish, MT Outlaw 56 Ford F-100's

Hmmmm… Interesting point regarding corrosion of the aluminum heads, Stuey.

Regarding cast iron, don’t let the thickness of a cast iron section mislead you. Cast iron is brittle and uneven heating causes uneven expansion resulting in cracking. OUCH!

While composite gaskets may be supplied with the exhaust manifolds, consider an alternative for eliminating the potential corrosion issue resulting from the dissimilar metals being in contact.

Suggestion… apply a smear of Never-Seez to the exhaust manifold flange surfaces instead of RTV gasket sealer. In my experience, the Never-Seez has seemed to seal the joining surfaces.

Regards,

NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York

I've just been out to measure the manifolds flanges. the two outside and the centre are 3/4" the other four are 1" thick. aaaargh! up until now I'd only hung the manifold on the two outside bolts now I need 8 longer bolts. For comparison I have an EDB 9431 B the flanges measure 3/8" except the slotted end which is 1/2". Ain't no wonder they crack at 3/8". I'll use the composite gasket that John supplied to reduce dissimilar metal corrosion on the ally heads and risk a cracked manifold. The heads are worth more than the manifolds and at 3/4" thick the risk of cracks must be reduced. John, why two different thickness's ?The socket access is no problem using the small head ARP bolts and a 3/8 drive 3/8 socket.
stuey

I have the Speedway version. I used the bolts (and gaskets) that came with the kit. IIRC all bolts are the same length. The breakage issue is news to me. The rebuild kit had exh manifold gaskets as well. Could it be over torqueing is part of the cause? It's only like 25 ft/lb. required.

Oh and BTW, I'm really surprised nobody here has mentioned a modified 9/16 socket. I have one I shortened back in my SBF days. It came in handy when torqueing the center bolts on these ram horns and it got used for combo manifold install on both my 223 and 240/300 sixes.

Use in conjunction with a wobbler extension or a U joint.

The manifolds should take (4) 1-1/2" and (3) 2" bolts per side

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