The most terrible thing (so far) on my 735i happened yesterday. It was a warm day (read 35 - 40C)and I had been driving for about 30 - 40 mins and then the car started to flat at 2000RPM and then ant 3k and 4k and was shuddering all the way up the rev range! Am I right in thinking I need a new set of spark leads? If so what do people recommend. The factory ones are pricey, so I'm thinking about going generic. If anyone can shed some light on this that would be great. Oh its a '81 735i manual RHD