lookin serious Martin
and on that note, weight is the enemy of acceleration. And acceleration is not just on the "forward" axis. Braking and left and right turning are also effected by vehicle weight. And a lighter car "feels" lighter too, very nice to drive for motorsports, not comfort.
As well you can run smaller effective(read lighter) brakes, smaller (quicker spooling) turbo and more streetable, torquey cams and have an equivalent power/weight ratio to a very powerful but very heavy car.
also, a light car has less stress on all its driveline parts, clutch, axles, gears etc.
and hey, you will get better fuel economy too
89 lbs is a good deal of weight. I have taken 200lbs out of mine since it was stock. My cabin area is virtually stock however. Altho with the addition of the bigger turbo and (moreso) the 2 piston brakes/big rotors, I may have to re-weigh it.