What are the correct size wheel nuts for the classic UK imprezas? Do wheel nuts depend on wheel type (model) if so which ones are recommended size for Speedlines?

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I have speedlines on mine and I thought they were the same sized nuts as standard - until I had a puncture.
They are the same hex size (if thats what you mean?) but when I put the space saver on with the speedline nuts, it was almost as if the nuts were bottoming out on the thread. I drove very slowly home
I now carry 5 standard nuts with the wrench in case of another space saver experience

 

No the hex size is the same - its just the way the nuts "seat" on the rim isnt right

 

Didn't you get the speedline nuts with the wheels?
They are different profile- hence the problem I had with the space saver.

 

No I didnt buy the wheels new - will try to source some speedline fitment nuts - been running round on these for 18 months as they are but I have a feeling the wheels are trying to constantly part compnay with the hubs