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Discussion Starter #1
Hey guys I just pulled the exhaust manifolds ('71 GTV - two pieces) and when putting them back want to use new nuts. What came off look like regular steel. I've had much trouble in past lives with exhaust manifold nuts and studs becoming one piece. Should I be using a different type of nut and/or is there a treatment for the studs that will prevent siezing? I'm thinking regular anti-seize won't last because of the temperatur, right?
 

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Hi cabikefreak,
I believe the original nuts are made of brass. I have used the regular anti seize compound, and it works for a couple of years.
Ian
 

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Alfaholics have nice self-locking copper nuts for about $AUD1.40 each.

Mine are brass (12 or 13mm). Don't use steel nuts as they will weld on to the studs over time.

Chris
 

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Yes, ClassicAlfa and others have these nuts as well but the important thing is the 12mm head size which then allows a socket access.
 

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71 Berlina 74 GTV 17 Giulia Q4
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they've been brass since day one or at least back to 59, always nice to have a couple of spares as it's easy to round off the flats or strip them if you are just getting to know her.
 

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Gene,

Back in the day I purchased brass exhaust manifold nuts from Centerline... and a couple of studs as I needed one to replace...
 

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As well as the nice copper ones I've also got a box of the brass ones for people who want "originals". Same price as the coppers but make sure you specify BRASS when you order or you'll get the copper ones...
 

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Discussion Starter #9
Guys - I was at APC the other day and asked Stewart for his opinion. His advice to me was that unless I'm experienced w/brass or showing the car, just use steel. He cited that Alfa changed to steel at some point. He also said 13mm head size is workable if you are willing to modify a tool to fit the job. Given his experience and reputation, I figure this is another very valid opinion.
 

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A bunch of people on the BB recommended these elliptically deformed prevailing torque locknuts: Coast Fabrication's Online Store

On their recommendation I bought a set (haven't installed yet) but I don't know how they'll survive over time as they are coated steel not brass. They are rated @ 450 deg f - is this a concern? They are however very small (coastfab's site mentions their strength to size ratio) - I believe they take a 10mm socket!

What I took away from the BB conversations was that loosening over time is a common problem, and I suppose the brass nut + lock washer setup wasn't working? Can anyone comment?
 

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Not sure why you'd need to be "experienced with brass". Just tighten 'em on and don't overtorque 'em. It's not rocket science or anything.

The point of brass is that they don't loosen over time. When I got my Milano it had a mish-mash of steel nuts that would loosen and cause me to get exhaust ticking. Replaced them with brass nuts and steel wave washers and have not had any further problems since.

IAP sells an 11mm x 13mm crescent-shaped wrench that works perfectly for getting to the tough manifold nuts:

Manifold S-Wrench, 11mm X 13mm
 

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A bunch of people on the BB recommended these elliptically deformed prevailing torque locknuts: Coast Fabrication's Online Store
The Coast Fab nuts are great for race cars with aftermarket headers. I wouldn't use anything else. On a race car, the steel isn't a problem because they aren't on for years at a time. For my street cars, I just run the standard 13mm head copper nuts. Never had a problem.
 

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I have the copper ones from Alfaholics and they work great.

If you want to use steel nuts and antiseize go for it .
Antiseize is rated for almost the melting point of aluminum so
it will be ok .
 

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Well since I'm into them for thirty bucks, i'm gonna use um. ill let you all know what I find.
 
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