Tuning the fuel pump
The non intercooled models have a mechanically controlled fuel pump. These can be adjusted to give more fuel, which will give more power if there is sufficient air! The pump has only a couple of adjustments which need to be balanced to get good performance without too much smoke.
If I get time I’ll write a proper tuning guide for them but Rover-Ron has written a basic how to guide which will give you some gains. Given suitable mods the mechanical pump can give good results, one car I fiddled with made 145bhp on the dyno, (it was running an intercooler, bigger injectors and turbo but that’s about it).
The intercooled models also have some adjustments to make in the pump you can find details on that here