[woodcote]

Sounds like an exciting project!

If you're using Scalextric digital, use the Scalextric digital powerbase and the power supplies. This will provide constant 15V AC to the track - the amperage will depend on the powerbase model you are using (approx 8 Amps for an ARC Pro or six-car Advanced Power Base, each with two power supplies attached).

Because the digital command signal is sent via the track rails, you will need as perfect electrical continuity as possible - any power drop-outs also means a drop out of the digital command signal and that causes all sorts of problems. That requires a high standard of track construction (I think braid is preferred to copper tape for digital), maintenance and some power taps. On our 100-foot club circuits (built using Scalextric Sport track), we have three passive taps wired to the track piece next to the powerbase and radiating out to 25%, 50% and 75% of the track length (measured by number of track pieces). It is essential each tap connects the same rail, otherwise you will get a short circuit.

I hope that helps.