Thinking about jumping back on the Marea bandwagon after a few years off (Stilo...yuk, Saab 9000 fast but ropey, Saab 9-5....big and useless!) and I have my eye on a 20v 155.....I need it as a tow car for my single seater race car, but I also like a bit of extra grunt and would be looking at a remap/tuning if I buy it. What kind of extra power would I be looking at? How easy would it be to get to....say...175bhp???