Good Morning, you have a lively thread here!
Just to put a few things in perspective this is what my comments are based on and why I said them.
On a technical test track (Blyton) that is not a flat out flowing race circuit with special high grip asphalt the ZR was actually quicker. This was proven by 5 other professional race and rally drivers in addition to myself and as the Clio has more power and torque it was logical to assume the chassis was the reason why the ZR performed better. The cars were a standard MG ZR 160 3 dr and a Clio 172. Conditions were dry. We had a play with a 182 on a different ocaision, the ZR wasnt there and it was damp too so it was unfair to make a comparison, the 182 was slower than both the ZR and the 172, but we expected it to be owing to the conditions. A chappie from Regie UK also turned up with a v6 another time which was very quick!
For ref the brakes on a Group N car have to use O/E calipers and rotors, pads and fluid are free, jump hoses are recomended to protected (stainless braided are best) Master cylinder and servo where fitted must be O/E
The ZR 160 has 282mm front vents and 260mm rears. Single piston motorsport calipers as standard.
But back to my original point, a well driven ZR160 can beat a average driver in a Clio 182 on testing roads (not a motorway!) In just the same way a 182 in the right hands can spank a Subaru Imprezza