Still a good 1.5sec off the official figures with a 20 year old car, good skills. 
Official figures are always bullshit. According to official Saab figures my car will do 122mph max yet I've done 130mph. That said, when I'm driving my sat nav will say I'm doing for example 68mph yet my speedo will say 72 so...
The most I've got out of the BMW top speed wise was 80, I dare not go any faster because that back end, jesus wept. I've lost it only to regain it once or twice and to say its scary is an understatment. I remember my mechanic saying when BMW made that car, at the time, it was one of the most dangerous cars put into production. (He's owned a few) I have to wrestle with it just turning a corner. Its a pleasure to drive though and pisses all over the Saab in terms of fun and sheer driving experience.
Cars today are almost boring not only to look at but to drive, god knows how people reacted to the 635 when it first come out because today it just draws looks from all over. I love mine, when I slam that accelorator down the engine growls and the front seems like its about to take off, that and the back end sliding from side to side...
I think I'm gonna keep mine and hand it over to my son in 18 years time, god knows what it will be worth then.