If building a kit car, I'd go Megasquirt engine management, I built and used a Megasquirt 2 on a Nitrous'd Micra I had a few years ago (170hp at the hubs! 1.3 litre). Was very good.
You'll seriously love the power of being able to tune your own engine management, plus it simplifies the whole engine management arena something royal, it runs only the sensors it needs and you'll always have the power to diagnose any issues with your PC. Drop me a PM if you want any advice, I used to install ECU's into cars they didn't belong in on a daily basis for many years
If you're learning about automotive development, this is the zone in which to be, there are a million and one mechanical experts around, but very few people who know anything of any consequence about engine management systems.