Well, I had a 106 GTi and my mate has a mk1 172 and we raced them a couple of times, both on "private roads" and on a track.
In a drag style race from a standing start the 106 will be pretty close up until the 106s redline in 3rd then the 172 will just pull away due to its greater power & torque as the speed rises.
However, introduce some corners into the equation and it evens things up a bit.
To be fair, a 1.6 with 120bhp vs a 2.0 with 172bhp is hardly fair, but youd be surprised at how well the 106 uses that power!
According to Evo, the 106 GTi is 0-60 in 7.4secs, compared to 6.6secs & 7.1secs for the mk1 & mk2 Clio, so not too shabby, but its top end where the Clio wins hands down.
Mine was modded and running 141.3bhp @ fly when I last had it RRd, so was pretty quick and I could really give my mates 172 a run for its money. We did a trackday and it was only down the long straights where he had any advantage. In my opinion the mk1 172 is geared too long and the ratios on the 106 were much better, so always kept it in the power band.
Only downside with the 106 is that you need to rev the nuts off it to get it to go as there is not much low end torque, but hey it was fun!
Still, I loved that car and wish I hadnt sold it!