Turbo 280ZX has a double PCB ECU, the non turbo just has a single circuit board.
Turbos also had bigger injectors.
As a Tarmac rally car, you are given freedoms in brakes, for safety, not like in Historic Prod Sports circuit racing, and you can run an aftermarket ECU, not like in Hysteric prod sports.
If you really wanted to stick to stock Turbo twin board ECU, you would need to run bigger injectors, run an interuptor piggy back ecu from dizzy to stock ecu, also run an interruptor from the air temp sensor, the water temp sensor, and the low speed idle part of the circuitry from the AFM, if you were to run a more aggressive camshaft. the turbo housings A/R ratios could be changed, and exhaust is free from the first join after the cylinder head, ie dump pipe back
This is all for Tarmac rally use, ie Targa Tas, Highh Country, Targa WA and Classic Adelaide.
You cannot use a 280ZX in Historic prod Sports, as the cutoff year is the end of 1976.
This is why the USA Spec 280Z gets into Historics ( same as a 260Z shell,) it has to run the stock engine as in a Aussie 280ZX, a heavy r200, and stock interior, as well as stock brakes, mine weighs in at 1125 kgs, and she rocks and rolls like a pig, compared to my Datsun Sports 2000, at 810 kgs!