Will they work? Tired of the copper colored ones the Cap'n detested. I've never trusted the torque value due to the ovaled holes and the way they tightened.

Are you talking about the 911 barrel nuts

I looked at the ones at pelican. I don't understand how the barrel nut versions work using a hex drive.

Threaded on one end, hex drive on other end. I don't think the exhaust studs have enough clearance around them to fit the barrel nuts. I use the 12mm copper colored nuts on a 914. Gives you more room to work than a 13mm.

I just put some side by side. Diameter is the same because the 914 has a flange and the 911 does not. Also the 911 would be easier to tighten because no socket required. Problem I am seeing is the 911 nuts is they spin up freely and probably will come off just as quick. The factory 914 nut has a coil inside that grabs the stud.

I tried the 911 nuts and yes, they came loose. Went back to or original style.

I also tried the barrel nuts. Needed washers to space them off the flange and, yes...they came loose.

You guys are scaring me. I used the barrel nuts. Can’t remember but I want to say I use split locks on them?? With the stock HE’s there is one stud where you can’t get the socket on there. That one got a nut.

Thought it was an “upgrade”. Hope the stay tight!

I used barrel nuts on my MB911 heat exchangers, except the one that needs a regular nut. Barrel nuts are standard on many 911 heat exchangers and used on 914-6 HE's. That's why Ben duplicated the access tubes on his product.

The barrel nuts [ with allen heads] are used on 911 and 914-6 to get thru the holes in the heat exchanger. . If you have to use washers, the studs are too long. . The 12 mm copper nuts are used on the other studs because of limited wrench clearance between exhaust header and outside of wrench. . the front nut on the passenger side of a 914'6 is a real bitch. . you can see it and almost touch it. . I have a special bent up wrench just for that one stud. .

We call it an SSI wrench but real name is distributor wrench.

I used the 12mm nuts, I've checked and re-checked them, no exhaust leaks ever.

I think I have found some replacements for the NLA factory nuts. I ordered some. Not cheap but better than the $18 each for the factory nuts. Made of titanium with locking threads.

They look great

How costly are those made out of titanium ?

How about these ?
https://www.mcmaster.com/#95108a102/=1b7iz3e

$9.00/100

I bought a bunch of these SS flanged nuts that might be an option on heat exchangers

Bruce

Being stainless, do you think there might be an issue with the steel studs? I tried using SS hardware on the muffler to heat exchanger connection one time. Didn't work out so well. Perhaps the black phosphate ones might be better suited for this application?

I like the height of the ti bolts. Theres a lot of bolt to grab on to.

Do you have a link for where you found these?

EBAY 161892735045 3 to bag. 10.99 shipped

eBay link doesn't open on the tablet. It wants to dial that #. I'll look it up manually.

SSI once provided this wrench. 13mm !

The shape of the titanium nuts looks similar to the stock nuts, but my understanding is that copper plated steel was used originally because copper has high heat tolerance.

I think I'll take a swing at the phosphate ones. I don't mind a WRONG for $9 plus any shipping.

You do know that titanium loves to gall at the drop of an excuse, right? That's why machining it is such a pain in the butt, and why special coatings are always used. If they fail, the nut will pretty effectively bond itself to the stud...

--DD

From China

So to be clear you just want the copper clad 8mm nuts with 12mm head? I buy those by the 100s.. Let me know if you need some also ti would be less then ideal..

I use barrel nuts I got at Ace.
They are labeled JIS Nuts and take the smaller wrench (12 mm I think?)

I torque them to spec then double nut them with a second of the same nut.

I have headers that are really tight against the tube, so you cant even get a whole wrench on these nuts.
I had to cut out the side of a deep well socket to be able to torque them.

Titanium nuts came in. Thought I would post pictures. I see no reason not to use these. Lighter and stronger. Flange is a hair wider and a little thinner.

Make sure you use some really good anti-seize with those Mark; Ti threads gall very easily, especially if these is any machining chatter.

The phosphate ones WILL rust. I personally would avoid them. Remember the factory typically does things for a reason.
Our cars they tried to shave off every penny of cost. This is not an inexpensive nut to make compared to a normal piece of hardware off the shelf. Think manufactured cost of $1.50 each x 8, $12 compare it to 8x .12 for an off the shelf nut and your looking at $11. Multiply by 100,000 and the million dollar question is why did they spend more? I'd bet there is a good reason.

If course if there is a need I would be happy to make these.

Mechanic and I will be pulling the European Racing Headers off of the stub pipes while we try to fix oil leaks and swap the tranaxle for a Dr. Evil creation. He's advised me to buy gaskets (which I found) and exhaust-appropriate hardware (six pairs M8 x 1.25 x 25 nuts and bolts mechanical locking nut for exhaust), which I'm trying to learn about now.

I found these copper M8 (12mm external) nuts:
https://www.paragon-products.com/ProductDet...ck&CartID=1

What materials are best for the bolts? Is zinc coated grade 8.8 OK? We're going to need to pull this all off again when I upgrade to a Tangerine Racing exhaust in the future.

Yea, we like the 12mm over 13. easier to tighten down in tight spaces.
8.8 grade is fine. I use washers on each side of the flanges. A little anti seize can't hurt.

Slight hijack,

Type IV exhaust studs, correct length? and place to get quality studs at?

I found some copper plated nuts on Amazon that use a 10mm socket.

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