10mm Inconel 625 Head Studs for Porsche 911

10mm Inconel 625 Head Studs for Porsche 911, 964, 993 and 993 Turbo!

These are our best 10mm Inconel 625 Head Studs for Porsche 911.  You’ve already proven you don’t compromise by owning a Porsche, so don’t fall short where it really counts!  We’ve developed these for builds and customers wanting the best for your engine.

Why do I need these head studs if I already have 10mm head studs?

• Stock head studs age, crack, fail and generally need replacements
• The inconel alloy is super resistant to rust and corrosion for a long life.
• In testing these were able to torque as high as 75 ftlbs while still retaining a linear increase in clamp load vs. torque.
• These have the largest mid section that will clear liners and heads.  no machining required.

What do they fit?

• Pretty much every air-cooled 911 made!
• Porsche 911 (1965-1973)
• Porsche 911 (1965-68)
• Porsche 911L (1968)
• Porsche 911S (1967-73)
• Porsche 911T and 911E (1969-73)
• Porsche 911 (1974-1989)
• Porsche 911S (1974-77)
• Porsche Carrera (1974-89)
• Porsche 911 (1974)
• Porsche 911SC (1978-83)
• Porsche 930 Turbo (1986-89, 1976-77)
• Porsche 911 3.2 Carrera (1989-1998)
• Porsche 964 Carrera 2 and Carrera 4 (1989-94)
• Porsche 964 Turbo Coupe (1991-94)
• Porsche 993 Carrera, Carrera S, Carrera 4, Carrera 4S and Targa (1995-98)
• Porsche 993 Turbo Coupe (1995-98)
• Porsche 914, 914-6 (1970-1976)
• Porsche 914 6-cyl Targa (1970-72)

Do they require machine work?

• These 10mm drop in replacements do not require machine work to the case, liners or cylinder heads.

What are the torque recommendations?

• For engines prior to 1990 that have unsupported pads, follow oem torque recommendations within 10% as the stud strength alone will improve holding capacity.  But too much torque can warp the heads on the earlier engines.  For more holding capacity please flame ring the heads!
• For engines post 1990 that have a larger sealing area and the torque is pulling directly on the liner Settle at 15ftlbs, increase the torque to 30, 45, 60 then final torque.
• Depending on your build, heads and case you can increase the final torque anywhere from 60 to 70 ft-lbs following oem sequence.
• Recheck at final torque in a linear sequence just to be sure you’ve not missed any!
• We loctite them in the case on install and use motor oil on the threads when torqueing.
• There is no need to re-torque later as yield is about 30% above actual torque, so there’s plenty of strength left in these beyond the recommended torque settings.

What are other advantages of this head stud kit?

• No machine work required
• No special gaskets required
• Simple, drop-in replacement for oem head studs with the highest torque available on a 10mm head stud.
• The studs are longer for a deeper bite in the case.  Don’t worry, the case has plenty of depth there.  We’re not going any deeper than the original machinework in the case.

Why use Inconel if Chromoly could already hold tremendous power?

• The alloys in these studs are so corrosion resistant, they’re polished vs. coated.
• The polishing also helps reduce any micro stress risers that could promote cracking down the road.
• The 10 point 14mm allow a much easier install with a small socket which will clear the valve springs.
• These nuts are also forged vs. machined.
• After stretch testing these studs, the nuts spun on and off easily.  Even up to 75 ftlbs!
• Re-usable for the life of your engine

Point is, they’re simply better…

So, check out 10mm Inconel 625 Head Studs for Porsche 911!

Need help with the machine work or  Protomotive Porsche Engine Building

And be sure to check out our Youtube channel for some beautiful cars, fun videos and great tech.