21 tooth Cosa clutch on T5?

Hi all,

I have just ordered a 21 tooth closa clutch to upgrade / upgear my T5 a little.

Question is… can i use the original T5 castelated nut and fold-over washer to fit this, or do i need a different nut to fit the Cosa clutch?

Thanks guys and girls!

You need the cosa type nut. Use some loctite and do up to 35lb/ft

I used the original T5-nut with the fold-over washer, and so far it seem OK (I’m still running in the new cylinder and drive slow and easy). What can happen, - and why should I use the selfsecuring nut with washer that can be bought to the Cosa-clutch?

Simply because the cosa is designed to use this nut and also its a much better arrangement. The castlelated nut was a shit design. I dont think it will cause you any problems to use the old one though.