Porsche 12 point fittings are triple square a 90 degree angle between ridges hence the word "square"Jonnysc wrote:The 12 point female bolt heads are known as 'spline' drive, I believe. used extensively on new VAG stuff.davep wrote:Torx, what Torx? Not on any Porsche I know of. The 914 CV joint bolts generally use the tri-square (12-point) bolts.jackstowers wrote:My 914 had been butchered by someone not knowing they were originally torx and using the wrong tool.
having a 90 degree angle.
Spline has a 60 degree angle between ridges, the problem arises because most peoples tool boxes contain spline drives, very few contain triple square, use a spline to try to loosen a triple square fastener which is tight will result in a stripped fastener.
The problem results from the fact that a spline drive looks correct for the fastener but it's not!
The problem is further compounded because tool sellers often describe a triple square XZN as a spline drive which obviously it can't be for the reasons I mentioned above.
I'm sure from memory that my 964 has a hex bolt (6 sides) if your car has a 12 sided bolt ....it's XZN Triple square
Hope this helps
Edited to say I've just re read your original post and you say you've hex bolts as my 964 has try hammering the nearest size up triple square drive into what's left of the fastener, possibly you can then get enough purchase to remove them.