Several options...
1. You could always warm up to higher speeds...start at 50 or so and work your way up and see how it goes. That will test how important that $2k is to you....
2. You could borrow cash and secretly hook up your suspension to handle the speed, and then use the $2k to pay for the mods.
3. Just calibrate your speedometer to lie by about 30 mph, so you can take it at 50 but it seem like 80. A videocamera instead of eyewitness would be key though.
Now I would never do this, but I'm more than willing to support Darwin and natural selection on this one.