Here are a few engines being built at SUPERTEC

[Henry Schmidt]

3.2 Carrera being built for a shop in N.Cal. Note the SUPERTEC head studs

2.75 twin plug (70.4x91) for a 67"S" soft window Targa
2.8 liter twin plug short stroke (66x95) for sale

73 911s for customer in So. Cal.

2.7s cis engine for in house project car
3.5 liter twin plug Tech II 600 + hp for customer in detroit. This is his third engine from SUPERTEC

[magic930]

Great idea with the rubber bands on the rods!

[dd74]

Hi Henry: the 2.8 looks interesting? Any specs? How much $$$?

[garibaldi]

What are the "Supertec" head studs?

[Henry Schmidt]

Originally posted by garibaldi
What are the "Supertec" head studs?

Go to www.supertecperformance.com and go to new products. We have designed an all new heads stud kit that is far and away better than the competion.
The SUPERTEC head stud kit will soon be available on the Pelican parts web site.

[Henry Schmidt]

Originally posted by magic930
Great idea with the rubber bands on the rods!

The green bands are actually 3.6 cylinder base o-rings.
If you pay attention you can learn something new everyday.

[garibaldi]

Who is the competition? What makes the studs superior? What material are they made from? What is the tensile strength? I am interested, tell me more about them, your site doesnt tell much about them. Do you manufacture them?

[Henry Schmidt]

The competition is vast ( ARP, 993 factory, Raceware, Dilavar, SSF Super stud) and I believe that Pelican parts sells them all.
What's better about SUPERTEC head stud kits:
Longer threads for more depth in case.
Fine thread nut for smoother and more consistent torque.
Aerospace material.
Basic stud design the same as 935 Factory racing stud.
Nuts are 12 point serrated flange. ( great for twin plug application)
Harden ground washers.
Threads are rolled not cut.
Studs are ground to size.
Heat treated
Polished
Rockwell tested.
And I guarantee them against breaking for life, that's forever.

[garibaldi]

nice

[rick-l]

How do you get the cases so clean?

[Henry Schmidt]

First we throw the case in the dish washer, let it spin for a hour or so. Next we throw it on the ground and spray it with Red Hot. Then comes the magic part, we scrub it. We use a bristle brush and we scrub.
High tech or what ?

My friend just read this and he tells me if I don't show you a picture of our dish washer that one of you is going to email me telling me his wife just kicked him out for getting grease on her Mikasa china.

[KobaltBlau]

Originally posted by Henry Schmidt
The competition is vast ( ARP, 993 factory, Raceware, Dilavar, SSF Super stud) and I believe that Pelican parts sells them all.
What's better about SUPERTEC head stud kits:

...

Threads are rolled not cut.

Henry, any idea which of the competition has cut threads? I'm just curious even though I'm not in the head stud market right now, I know how much difference that makes on bicycle spokes

[Wayne 962]

Sorry, can't let this slip:

Originally posted by Henry Schmidt
The competition is vast ( ARP, 993 factory, Raceware, Dilavar, SSF Super stud) and I believe that Pelican parts sells them all.
What's better about SUPERTEC head stud kits:

Space age material.

Can you be more specific?

-Wayne

[A Quiet Boom]

Originally posted by Wayne at Pelican Parts
Sorry, can't let this slip:



Can you be more specific?

-Wayne

Yeah, we've been in the space age for over almost 50 years! LOL

Nice engines BTW

[Henry Schmidt]

The material was found in a factory race engine built by Porsche and made big HP in the 80s. You guess what it was
Here goes.
Remembering that I am a mechanic not an engineer the specifics are as follows:
17-4ph HCR 38-42 4hrs @ Temp 1025
http://www.latitudemanufacturing.com/174PHPrint.html

[David]

I am an engineer and we use 17-4PH turbine blades at work. There has been some stress corrosion problems with this material. I'll try to do some research at work tomorrow to see if it's a problem in this application.

As for the rolled threads, I doubt there are any cut OD threads on any manufactured fasteners anymore. If there are, I would sure like to know who, as would anyone that's buying them.

[A Quiet Boom]

I was actually teasing Henry lol I've been a big fan of ARP fasteners for years now on my watercooled race motors but I doubt they put a lot of effort into figuring out the whole expansion think on a 911 since the market is so small compared to their other applications. I don't know much about Raceware so your studs, designed by guys who race these engines, are of interest to me. I'm hoping to do a build up next winter and would of course be using top quality fasteners.

[David]

I couldn't find any SCC problems with this material in this application; in fact it has very good corrosion resistance compared to other fastener grade stainless steels. So it looks like this is a good material for head studs.

My only concern would be the coefficent of thermal expansion which is similar to Cr-Mo steel. Since it's much lower than aluminum, there will be a cyclic stress due to the repeated heating and cooling. Since the stress at temperature is much lower than the yield stress this shouldn't be problem either.

I couldn't find material properties for ARP or Raceware, but I'll give them a call later today if I get time.

[MotoSook]

Henry, were the "found" studs on an engine that came to your shop? I like your lifetime gaurantee! ...nice engines!

I think "shifter" has it right, most OD threads are rolled these days.

Here is copy from a site that sells ARP studs:

"our Porsche 911/914-6/930 studs have rolled threads, fine threads at the head end of the stud for more accurate torquing, and include a 12-pt hardware kit, complete with nuts and washers, and ARP's special torquing lube."

More:

"The ARP 2000 material used to make our Porsche 356, 912, 914 and VW Type 1 and 4 head studs, thru-bolts, and connecting rod bolts is about 33% stronger than the stock material, with a 220,000psi tensile strength and improved fatigue characteristics. That’s even more than typical chromoly studs which advertise strengths of 180-190,000 psi, but rarely live up to their promises! Additionally, our ARP studs have rolled threads and the ARP 2000 material does not suffer from stress corrosion and hydrogen embrittlement, providing care is taken during installation. "

I wonder what the the ARP stud is made of and the factory 993 stud material?

[Jim Sims]

http://www.arp-bolts.com/pages/tech/matspec.html

The ARP alloys can all be mapped to standard commercial alloys or modifications of commercial alloys. The Russians apparently have a "super" multiphase alloy containing some aluminum developed during the cold war; some tests have been done on it (it's good stuff) but we haven't pursued it as they have now patented it and may be producing it commercially.

The best available overall stuff for head studs is probably ARP3.5 (MP35N); it is hard to beat for a combination of strength and corrosion resistance. It is likely an overkill choice though given it's high cost (35% cobalt content). The 17-4PH while just barely a space age alloy (there were V-2's being launched when it was introduced to the aircraft industry after WWII) is a good choice for head studs but only because this application is less demanding strength wise as the Porsche engine case base metal (Mg or Al) will likely fail first even with thread inserts.

As an aside, 17-4 PH would not be a good choice for rod bolts (it's too weak) and I don't think you'll find anyone using it for such an application.

Cheers, Jim