billindenver

Anyone know what the stock exhaust studs are made of? Or the thread pitch and length?

billthe3

Don't know what the stockers are (they definitely are not stainless though - mine were completely rusted over), but here are some good stainless replacements.
http://www.rennspeedracing.com/ss_exhaust_studs.html

billindenver

Those are what I'm replacing. Not working at all for me....going back to stock type.

sharky47

What about them do you not like? - I'd really like to know.........

BTW, the stock ones are some kind of carbon steel - maybe 1018, but I am not sure. Thread is M8 X 1.25mm

billindenver

Not sure the metallurgy works in this application. Copper nuts, despite anti sieze on them locked on so hard that the allen snapped off inside the stud 3 times trying to remove the nut. Broke off a lowes allen, a Home depot replacement and then the craftsman allen cracked the stud. (after one month of being installed). When I double nutted the other end trying to remove the copper, the double nutting stretched the stud and ruined the threads (tightening the steel double nuts a little at a time trying to get a lock). I think you have a great idea there, but there are a few things I would change.

1. Make the long end at least 1/8 inch shorter, probably 3/16 and maybe 1/4.
2. Make them out of higher grade metal, double nutting with small hand wrenches should not damage an exhaust stud. Would rather have grade 8 or 10 than stainless personally.
3. The center ridge where the threads change direction could be more centered so you can drive the stud deeper into the head...that might fix the length problem. I tried flipping them and putting the long end in the head but that left the ridge out to far for tightening the headers down.


All in my humble opinion only. Again, I still believe you have a great idea there....but tomorrow's track event is history if I can't find a local stud supplier. My own fault for putting the assembly off, but work has been long days trying to insure I could make the weekend. Such is life, eh?

It is entirely possible that other than the metallurgy they may be the same as stock (length), admittedly the stockers can be difficult when pulling the headers but I always managed..these would not allow it. I just put the length modification in as a suggestion because 1/4 inch hanging out of the nut is wasted stud and without it removing the headers would be cake. My main concern is the metallurgy....I seriously used small 13mm wrenches to double nut and it destroyed the stud.

sharky47

Did you use the Paragon "copper" nuts? Those things have become a thorn in my side. The problem is they are NOT actually copper, they are copper-clad 400 series stainless! To make things worse, they are partially crushed to provide the self-locking feature. I do use these nuts with my own stainless studs that I have run in my daily driver for about a year now, but I put a good coat of anti-seize on them..........

The problem goes away when you use the factory nuts, but not everyone wants to use those. Anyway, PM your paypal address and I will refund your money - I don't want to have anyone unhappy with something they have purchased from me.

sharky47

Oh and, the lengths are the same as stock - not sure why the clearance was different........hmmmm

And that's strange that you were able to hurt them - I did a TON of destructive testing including: twist-off, stretch, extreme heat under tension to measure stretch, etc. I was unable to break them using "normal" tools and upper body strength, i.e. realistic situations.

Oh well, like I said - just PM me your info. I sure would like to find a source of ACTUAL copper nuts to use with these. I am also thinking about making my own brass nuts - we used these all the time on piston aircraft exhaust studs with great success.

schwank

Now that is support. Kudos to you Dan for standing behind your work.

I'll be ordering a set of the intake studs today. I know they shouldn't be so bad as the exhaust ones, but would you still recommend using the paragon copper nuts or ???

sharky47

I used them - but I still don't favor them. Good thing about the intake is that the temps are much lower and you can get away with a quality fiber lock nut - or just a good ole nut+lockwasher.

Do use locktight between the stud and head though, blue works best.

gregeast

Hi Bill:

If you're going to be messing with studs do yourself a favor and get the exhaust studs from your local Saturn dealer. No, really. The Saturn studs have a torx end on them that you can use a torx socket on, which makes installation and removal much simpler.

Saturn Exhaust Stud
Ask for exhaust studs for a 94 SC2 and the part # is 11518152

I think I paid under $10 for all 8. I did have to call around to several dealers to find one that had them in stock, hopefully you'll get lucky and find them locally in time for Pueblo.

Here's a pic of the copper nuts and the Saturn studs in the car:

billindenver

Sharky, I do appreciate the way you stand behind your product. I'm not going to accept a refund however, as I bought them from you to support a Rennlist sponsor and there is no way to be sure this isn't some sort of user error. Maybe my anti sieze is wrong, bad or cooked off because I didn't put enough on. Maybe I should have gone with stock nuts over stainless studs in the high heat area of the exhaust manifold, maybe paragon's nuts just suck....who knows what went wrong. Point being, I want your company to succeed and continue to give us hardware options. Consider this as just a data point, if it happens to others then maybe there is something to look at...if not, it's just an anomaly.

sharky47

Man, I am going to feel bad if I don't do something - tell you what, I am going to start exploring different nut options. You will get a prototype set free when I get it finalized for you to test out if you want.

The Paragon nuts are fine, they just don't work all that well with my studs due to inherent galling issues with stainless-to-stainless fasteners. This is why I am going to see if I can just make my own - that way it just works and you don't have to think about it.

KuHL 951

Greg,
Have you tried removing those Saturn studs yet? My BMW uses the same size stud and I used them after a HG failure. The gasket leaked about a month later and when I tried to remove the studs I stripped the Torx head on over half of them. This was on a head I chased the threads on, copper nuts, and used anti-sieze. It seems the studs almost become embrittled after heat cycling. I have a set of Sharkey's studs for the 951 rebuild and know I won't be using the Saturn studs again. Now I wonder if I will just stay with stock studs. Hopefully Bills' experience is just an anomaly.

sharky47

Kuhl - try my studs + factory nuts. The factory nuts are made of carbon steel, so there will be no chance of galling - plus they have a different method of self-locking that is more "civilized" than just deforming the nut.

KuHL 951

I'll give it a try although the copper nuts on the saturn studs wasn't an issue, they backed off fine. It was the small diameter of the Torx end on them. I was told by a Saturn guy the the Torx is for installation only and weren't useful in removal. That's why I wondered if that small allen on yours would be the same problem. The whole benefit if using a special stud for me is to 'remove' them on a turbo for ease of header removal. I'll give yours a try...any hints on what anti-sieze you prefer for the exhaust side? I used a copper based type.