Oil pump priming..... weird bolts?

[DaveEFI]

I remember there was one which was a pain to get out, even on the stand, wouldn't like to try on a engine in the car! You can also get Allen key head ones which I remember thinking might be an easier option. eBay sell both in stainless! My originals were quite corroded as well.

Personally, I'm not keen on allen head thingies - they are more easily damaged than normal hex and then difficult to remove. Torx would be my choice where a small head is needed.

[Will Reeve]

You can definitely put more torque through a torq!
I've had a few nightmares with both female and male torq bolts. The rear diaphragm on a BMW V8 is case in point, you can 'just' get a torx bit into them but if you are not straight you strip out the bolt and it's a manifold off job!
The larger ones work well in head bolts. Vauxhall like them and it's amazing how much they take without stripping!
I was very surprised to see them on the Rover to be honest, though they were too modern.

[DaveEFI]

You can definitely put more torque through a torq!
I've had a few nightmares with both female and male torq bolts. The rear diaphragm on a BMW V8 is case in point, you can 'just' get a torx bit into them but if you are not straight you strip out the bolt and it's a manifold off job!
The larger ones work well in head bolts. Vauxhall like them and it's amazing how much they take without stripping!
I was very surprised to see them on the Rover to be honest, though they were too modern.

The SD1 uses Torx for the door lock catches and seats.
I think the problem may be they need a hardened head - so might make them expensive for general use.

[Gibson]

My bad.... they were 12point imperials but my imperial spanners were all six point so i had to beg borrow or steal before i got them apart. all sorted now!