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I'm about to re-torque my manifold bolts, but they have a "star-shaped" head (12 pts.?). What are these bolt-heads called? I'm trying to find a set of sockets, but can't conduct an e-bay search without a proper name.
P.S. - The points are facing outward, not inward (e.g. allen-head).
Nope...they ain't Torx. The bolts have their points on the outside of the head. It appears you would use a standard socket, only with a bunch more points to it than usual.
Here's what the bolt-heads look like. This set (called XZN) would not work as they are matching the bolt heads (I need a female socket, not male):
I had the same and what i did was went to the Tool Store and got a 12 point Socket that fit. They where also used on the drive shaft U-joints. I just bought the ones i needed as i didn't need the whole set. Sorry can't remember the name but shure they are just called a 12 point socket.
Sorry can't remember the name but shure they are just called a 12 point socket.
12 pt. sockets, as I know them, are just like six pt. with more points for better gripping. Looking at these bolt-heads, they are almost round in appearance.
I hate 12 point bolts. They are good in low torque applications. I seem to round them off in high torque useage.
I always thought that the 12 points were used for higher torque applications because of the increased surface contact area for the socket. Kind of like the thinking behind the 26, 28, 31, 33, etc. spline axles; the higher the spline count, (usually) the higher power/torque it can withstand.
Interesting subject though! Most people either hate them or love them!! Very little in between!
12 point sockets will round a bolt head much quicker than a 6 point will. The advantage of a 12 point is that you can get on the bolt head much easier as the 6 point has to be in exact alignment to fit onto the bolt. The 12 point does not put nearly as much metal into contact with the bolt head is why they will round easier.
Now, if you have a 12 point bolt head like this thread is talking about then you have the best of both worlds and rounding should not be a problem. I put the 12 point bolt heads on my intake manifold as the heads were only 3/8" and it made it much easier to get onto.