I'll post a few I found, feel free to add your own strategies:
-Lightweight Chassis (60s airtime)
You'll be using the construction site in McClane, with the billboard jumps over I-92 (one in each direction). You can get 2-3s airtime each way, drive a little further after landing, 180 with the airbrake and head back again until it totals 60s.
If you have Aero Body (pro only), Powershot Nitrous, or Off-Road Tires, equip those too, as they'll help you hit the ramp faster and fly further.
Long Gears (5000 yards oncoming)
Get on an open section of I-92 and stay in the inside lane (closest to the median). Make sure your entire car is in the lane, being on the shoulder doesn't count. The inside lane generally has a LOT less traffic.
Re-Inflates (hit 5 spike strips)
For an easy (but time consuming) way to do this, just run the #9 Blacklist race 3 times, and make sure you hit the 2 spike strips. Both are scripted right before repair shops, you can drive through the repair shop if you don't want to wait for the tires to re-inflate. --- Faster, faster, until the thrill of speed overcomes the fear of death.
This is pretty self-explanatory, but a great place to do this is at the Airfield, where there's a large, relatively flat open area with no traffic. Also, try equipping nitrous of some sort so you can read the ticker at the bottom right of the screen. Tight diameter drifts can be classified as "donuts" and not qualify, even if you don't actually go in a circle like a donut.
Also, to correct the Long Gears suggestion, it's actually 10k yards not 5k. Oops. --- Faster, faster, until the thrill of speed overcomes the fear of death.