For Turbo Track, you'll really have to cut through the grass on every turn by hopping through it with Blue Fire as seen in the video. You'll have to keep it as much as you possibly can, especially through the s-turn as you use U-Turning to get through seen in the video. Other than that, hit all the boost pads you see in the video as well. For Drive-Thru Danger, you'll have to take every shortcut that you see in the video, utilizing U-Turning throughout a majority of your run. Blue Fire MUST be kept for the entire run once you get it, losing it means you'll have to restart. In general, analyze my runs and try your best to replicate them. I believe you can do it! Hope this helps! :D