Does anyone know why the Haynes manual states " if Torx drive head bolts have been used then these must be replaced"
Cheers
John
It's because they stretch permanently when you torque them down then give them and extra measured 45 deg? turn.
If you reuse them then you will be stretching them a second time and you would be risking uneven tightness or even failure.
HTH
Mark
What Mark said 
The newer pinto engines with the torx head bolts have to have the bolts replaced everytime you have the head off. They arent that expensive.
The older engines used different bolts that could be reused twice i think. You can still buy the older style bolts if you want to...
Thanks Guy,s but from a Ford dealer they are £3.50 each
I buy em of fleabay for about £10 per set - they seem ok 
THANKS !!!!!!!!!! saves me about £25
quote:
Originally posted by Tinks
Thanks Guy,s but from a Ford dealer they are £3.50 each
Just found a Motor Factors in Bradford near where I work £1.20 a set getting better
John
Torx seem the best bet for replacement despite the slightly higher cost. You can re-use the older type but you have to re-torque them after so many
miles or something which means taking the rocker cover off again.
On a connected note, I want to change my camshaft and have the older head bolts, so I need the spline tool - anyone know the bit size offhand.
However, since I'd have to get the tool, and replacement bolts and a torx bit I think I might just lift the engine out. Why can't the cam
come out forwards!
Because it physically won't go through the holes?
Yeah I know it won't, I guess what I meant to say was 'Why oh why can't the bl**dy thing come out forwards'