Titanium Wheel Studs on a 996: Easy Mod, Expensive Mistake

I recently completed a wheel stud conversion on my 2001 Porsche 911 Turbo using titanium studs and wanted to share a quick lesson learned. This should have been a very straightforward DIY. I�ve done stud conversions before using steel hardware without issue. This time I decided to go with titanium for a higher-end setup since I remove my wheels fairly often (brake work, general maintenance, etc.). Where I made the mistake was assuming the torque spec was universal. Allen head studs (installed with a 5mm Allen) should only be torqued to 15 ft-lbs. Bullet nose studs installed via the double-nut method can handle around 30 ft-lbs. I mistakenly over-torqued one and snapped it during installation. I�m not a mechanic � just an enthusiast who works on his own car � and sometimes even simple jobs can trip you up if you don�t slow down and verify the specifics. Google gives general M14x1.5 numbers, but it doesn�t always distinguish installation method. Sharing this in hopes it helps someone else avoid breaking an expensive titanium stud on what is otherwise a very easy DIY. Full video walkthrough here if anyone�s interested: You Tube

That’s a bit of a bummer! Thanks for the lesson learned.

That looks like an Acer TI stud kit. I have the same one installed on my 2001 996 c2... Luv it. I used German Porsche torque specs of 'gud en tight' Don't take this as a negative criticism. Its meant to help/& share my knowledge of Mechanical engineering and many many decades of experience. Yup I'm an ole man. When looking at your vid, on the first stud you installed, noticed how you had to re-adjust your position and angle of that not small torque wrench after you seemingly thought you got enough tightness' on it to start with. But no, you needed to get the torque wrench to click/beep, even though you might have known it didn't feel' right. . But you needed to adjust too get enough leverage on it to get what you were told was the right torque. You had it right to start with, without adjusting for more leverage, without the click, just by your feel... Sometimes when using a torque wrench we fail to use common sense of our 'wrist torque wrench'. 1) I've seen published incorrect torque values many times where I've had to stop applying more pressure because my wrist told me this was max for this fastener after I felt the fastener start to stretch. 2) Sometimes a burr or bunged up threads, or dirt/debris in threads can cause a fastener to not torque correctly and you can ' feel it' if you just don't go by the torque wrench 'correct' setting, and use not so common sense. and 'feel' what you're actually doing. Its time to back the fastener back out and start again from scratch... 3) A key giveaway to incorrect torque specs is when the specs tell you to over torque the max torque capacity of the tool, like in your above case. A standard 5mm hex 'Allen' tool max torque is somewhere between 10.5 to 14.5 ft-lbs, says my old M E text books... A 5mm hex is a very small tool. I'm surprised you only broke 1 stud and only stripped out another 1, and the tool didn't snap, it can't handle 25ft lbs Just trying to help you and other young wrenches here to be more aware when using a torque wrench and realizing any wrench is only a tool to help you, and not the holy grail to tightening nuts/bolts while being oblivious to signs the tool is giving you, like stripping out its hex on previous studs... You're not alone here, I've seen many young wrenches oblivious to anything but the click/beep. That might be fine for most clamping/fastening of parts, but eventually you will find one it won't be fine. A great mechanic needs to 'feel it out' on every fastener he uses before doing any damage.... jmnsho

That was unfortunate. Not to steal the thread but love your garage flooring. Can you point me to the brand?

To be fair, these wheel stud 5mm Allen hex is a confusing fastener for those using a torque wrench. Especially if you don't realize what that 5 mm hex is really trying to accomplish for the wheel stud installation. We've got a wheel stud that is torqued to around 96 ft-lb torque, and we've got a small 5mm hex capable of max 10-14.5 ft-lb torque. No way that tiny 5mm hex will put any meaningful torque on that beefy large stud. So, we've got to think that hex is not really there to apply any meaningful torque. No, hex is there to help us fully spin in the stud to the very bottom of its threads with a good helping of lock-tite. Some stud kits come with a small Allen hex wrench maybe 3 or 4" long just to help spin in the stud to bottom it out in threads... Thats why many stud kit manufactures don't have a specific torque for the hex/Allen.

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The question I have is how you get the dirt out of the recesses of the flooring material. Or for that matter, what about the water that drips off your car? Even if you never drive a wet car into the garage, what about the water that drips off after you wash the car? Even if you dry it outside, you'll get some water dripping off a newly-washed car.

It�s hard to believe that a titanium wheel stud snapped at 30ft lbs of torque I�d think the 5mm hex would strip long before the stud would shear/snap� I�m thinking defective stud�

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Ebay. It's smart the op got rid of them.

From a quick glance at the video it seems part of the 'wall' around the female hex broke away. It did not break the stud where it had full cross section. Good hex bit, too much torque and not the best design/manufacturing to interface with the fitting tool did it

Ahhhh� I didn�t watch the whole video makes more sense

After I got my Acer wheel stud kit here on our forum, from a well know forum member, for a great price, as he had questions/concerns about his new never used TI stud kit for racing applications. I told him I would get them Rockwell hardness tested by my engine guru machine shop guy that does my crank balancing, as he also grinds cranks and does Rockwell hardness testing. The Acer Ti Stud Kit came back with a very high test results he said matched a OEM Lamborghini TI stud he recently tested for same reasons as above.. I don't remember the exact # of test results as it was a few years ago. I do have a print out of the test results somewhere, I'll look for it and post it.

I�ve had them on my car for over 5 years (I don�t remember which brand they are but they were neither the cheapest nor the most expensive - I�m thinking they were $2-300US for the set - I think I got them from ECS�) with no problems at all. I�ve also got 15mm spacers all around�