Re: new to 145
The 155 and 145 are basically the same car, same engines, same wheelbase, same transmission (although shorter gear ratio in the 145 2.0L compared to the 155), same suspension setup and same steering rack etc.
Agree with Purple145's post above that the older alloy topped engines are better for your purpose.
However its actually the ECU that makes the difference - the engines are completely identical in every way except for the cam cover (which has no affect on performance).
On the plastic topped engines there is some sort of variable venturi system in the intake manifold but tbh it adds complexity for no extra grunt imo.
The earlier alloy topped engines use two types of ECU, Bosch 2.10.3 and Bosch 2.10.4
The 2.10.3 is identifiable by having an EGR valve fed from cylinder 4 exhaust port and this is the guttsier of the two. Variator control is better on the 2.10.3 and generally kicks in higher than on the later 2.10.4 system. This is what I'd recommend although you are limiting yourself to an early 1996 motor.......
Way I look at it , the earlier the ECU the less trimmed down it is for emissions purposes, with one exception - there are some 155bhp motors going around, but these were cut back to 150bhp again for emissions. I dont know the exact ECU version of the 155bhp version but this could also be an option.