Thanks for all your suggestions. Tried all sorts at the weekend eventually ending up running a gear ratio of 4.0 and almost max motor timing with throttle expo at -40%. This seemed to be the best option and was certainly for my style of driving the quickest option setting a PB with this car and speedo and being only 2 seconds off my best ever on the track I was on.
Only thing I did not try was running a higher gearing and no timing. That will be my task for next weekend.
Thanks to all you made suggestions your help is appreciated.