Just wanting to know what is invloved in getting a jatco 3speed to shift properly after engine modifications have been made.(changes in vaccum)

I was thinking oneday a mild a14 may end up in front of the auto. (extractors,little cam 23/60, twin su's and a little higher compression)

Whats in need of changing. Is is simple enough to modify the vaccum module yourself in order to get it to shift where and when you want or is it a case of take it to the auto bloke.

cheers