IMO try the Ram-Air.
I've had one (89GT, home-made) and it helped from a slow roll
to 140+ MPH. But that was with the stock airbox, which I assume
the March uses. They do work, I've made them and used them,
but I will say this, buying a new one may not be a big boost over
a good CAI. I'd personally re-design the whole inlet tract.
I like gears like Monkey lists, for overall starters, however
I'm going with 4.10s and a manual with extended RPM capabilities
when I build my own street/race V6
