K-series engine

Now I respect your opinion but how can you say that my claim that there was a design fault of the *original* gasket is "piffle"? , and there is *No* way you can re torque a stretch bolt!. Did you do a different C&G course to me?.

I slacken to 50% torque (I have a crude but accurate mechanical pointer torque wrench which works in reverse), then reapply, then the angle figures.

I havent a clue but if you check with one of the Lotus Elise or MGF forums I am sure you will get a response.

Tim..

Not at all. Stretch bolts are stretch yes, but you never stretch them past their elastic limit. If you did then they keep stretching then snap and wouldnt hold ham in a sandwich. I am sure you are familiar with this.

Secondly, the HG's Rover started off with were not good enough for their job. Which is why Rover superseeded the part so many times in an effort to find a design which worked well with the type of engine construction the K series is.

Tim..

The reason you call it a stretch bolt is because that's exactly what you do, thus guaranteeing the clamping force is independent of the friction. They'll only keep stretching if you keep turning which is why they're not tightened to a specific torque.

Is that not what I just said?!

Tim..

No, they do actually stretch past their elastic limit. That's why there's a length limit e.g.

why they're also referred to as TTY, torque to yield bolts. Once you reach the yield point tithtening them further doesn't materially increase the clamping force so you get a nice consistent clamping force even with some errors by the operator or in the threads etc.