33 replies to this topic

[bmcecosse]

Torquing the extra studs to only 25 ft lbf is a waste of time - they may as well not be there! I did obviously have them on my S engines - but the non S engines I have never bothered. The fact that the most highly stressed A series from the factory (Turbo) didn't get the extra stud/bolt tells me they realised it's really not needed....... I'm actually surprised that no-one has suggested increasing the stud diameters to 12 mm or 1/2" - which would allow more torque on the head nuts - if it's felt that would improve reliabilty.

[Artful Dodger]

ok, to be honest i just wanted the experience and the knowledge first hand so i can be able to do it in the future. me and my dad have discussed the scenario oh the block cracking, and we cannot see any reason why there should be any lateral stress on the block unless the stud bottoms out. then there would be lateral stress. and we have calculated it. it doesnt bottom out. so it wasnt a waste of time. and as we are running a compression ratio of about 10.5 to 1 id rather have some more security of the head to the block. as there is now a much higher compression ratio compared to the old 8.5 to 1. there is more metal between said stud and the end of the block than there is between the bores, and they have been good for 18 years.

not a problem in our eyes.

[minibugga]

May I ask how far did you drill into the block on the 2 extra studs?

 

Cheers, Gonzo

[59 Speed]

I measured the length of the thread on the studs and used that for the hole depth.

Hope this helps.

Ian