Alan, I don't think that a Rover 220 Turbo would fit in CSCC "Tin Tops" - the proposal is for original turbo charged cars up to about 1400 cc, I think. Your car would fit very well in "Future Classics", though. A similar "mini-enduro" series; have a look here:
http://www.classicsportscarclub.co.u...reClassics.htm
Your car would fit in to Class D (cars up to 3 litres - turbo charged jut go into a class one up from their nominal capacity), where it would compete against 2 or 3 Porsche 944s (2500c and 3000cc), a BMW M3, an Alfa Romeo GTV6 and a Rover Tomcat. I am sure that your car would be very competitive.
The results from the recent Brands Hatch Indy circuit race are here:
http://www.tsl-timing.com/cscc/2008/81764.pdf
and the Snetterton race is here:
http://www.tsl-timing.com/cscc/2008/81464.pdf
This gives you an idea of the grid and the relative lap times.
Bear in mind that some of the participants were the reserves from the "Swinging Sixties" race but the CSCC is comitted to developing the "Future Classics" series (and the "Tin Tops" series) for the next few years.