I've got a mars red mk1 1.8 gti 8v. I've changed the suspension and brakes, but pretty much stock apart from that. Being a mk1, it will keep up with the Scoobs on the twisties, but they have the advantage on the straights!
Before the mk1, I had a stock 8v mk2 which I took to Blyton a few times (which included my first ever trackday
) I bought that car for £600 and with a decent set of tyres and a cheap Blistein suspension kit fitted, it coped amazingly well and could keep up with some cars costing over 10 times as much!
Hope to see you on 8th April, I'm sure you (and your mk2) will enjoy it!