No offense to anyone but I put more faith in suzuki's standard power claims than the various dyno shops around the world. Its not uncommon for them to be a bit optimisitic - someone showed here that people will always come back to a dyno that gives a slightly high readout.
I don't think there's an NA (engine mods only) micra which could take a standard GTI and give it a spanking down the quarter.
Its very much possible for it to happen - the potential is there. Heck, I give GTI's a scare until about halfway through 2nd gear and my car is pretty much standard.
The swift has a higher redline and longer gears too. It'll most likely have a higher trap speed than the micra.
I think to get a micra keeping up with a GTI after 2nd gear you're gonna need more than 100bhp. A higher redline is a definate requirement and longer gears will also come in handy. And lets face it, neither of those things is particularly easy to get and make work. More revs will almost certainly mean a bottom end rebuild for most CG's with uprated bearings, balanced crank if you dont want to be replacing the bearings with your spark plugs, headwork to make it flow enough to support the high rpm requirements (the suzi head literally flows TOO well for the motor).
Alot of work to say that you're quicker than a standard GTI in a straight line? Hah. Whatever. I didn't buy a micra to go fast in a straight line anyway. If I wanted to go fast in a straight line I would have kept my old SR20DE powered N14.