2023 Poll - 993TT all thread Dilavar studs - has anybody seen one break yet?

[LukasM]

Hey guys,

This is an age old discussion that seems to split the Porsche world in half... There are lots of haters of Dilavar studs, and rightfully so, as they are their frequent breaking is the main reason many air cooled 911 engines have to be rebuilt sooner than would be required otherwise. My own 3.2 has a broken stud, and this happens even on engines that are just sitting around.

On the other hand there are quite a few well respected engine builders that much prefer the thermal expansion properties of Dilavar over steel/ARP/Supertec etc studs, to help with head sealing and clamping pressure, both hot and cold. According to them, the latest 993 Twin Turbo all thread type with the black coating does not have a problem with breaking any more.

Given that they have been around for long enough now, has anybody actually had one break yet?

Asking for a friend....

Cheers,
Lukas

[Flat6pac]

Luke, I bought them in the 90s at $12 or so each and put them on my 76 turbo
$50 each, when supertec has their most excellent set for half that, and fine threads on outside to torque with
They’re a real pain trying to hit a 10 mm hole in the cylinder 4 at a time.
Bruce

[Bill Verburg]

Originally Posted by LukasM

Hey guys,

This is an age old discussion that seems to split the Porsche world in half... There are lots of haters of Dilavar studs, and rightfully so, as they are their frequent breaking is the main reason many air cooled 911 engines have to be rebuilt sooner than would be required otherwise. My own 3.2 has a broken stud, and this happens even on engines that are just sitting around.

On the other hand there are quite a few well respected engine builders that much prefer the thermal expansion properties of Dilavar over steel/ARP/Supertec etc studs, to help with head sealing and clamping pressure, both hot and cold. According to them, the latest 993 Twin Turbo all thread type with the black coating does not have a problem with breaking any more.

Given that they have been around for long enough now, has anybody actually had one break yet?

Asking for a friend....

Cheers,
Lukas

I used them on my 993RS rebuild 20yrs ago, still going fine.