First, don't start the challenge right away. If you have played this before, you may notice some infuriating obstacles that come out of nowhere and crash right into you. It's like they are programmed to spawn and just go over your path. So don't start the mission, instead, let them know who has priority on this street.
You shouldn't have gone into this road, mate.

Now that we have cleared our path, start the challenge and plant the GE-64 (explosives) on the front of the car. Yes, this is the only thing you can equip once you have entered a challenge. And yes, we are doing what you think we are doing. Now get those C4 placed symmetrically before the world begins to be annihilated by the icon of sin you have just created.
Yes. Thats more like it. Good boy.

Once all is prepared, get in the car and start driving. Try to avoid any route that may cost you more time that you would like. Anything can be done here, as long as you approach the objective by the beach and pointing to the rock (not the small one, the other rock more to the right). Note that you have to be there with 2:25 in the timer, or just be luckier than any human has ever been.
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In case you still don't know any good routes, here's the one I found easiest that gets you just in time.
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Now that we are in the end, aiming for the rock, right when you are about to touch it, go to the left (so that the only part that touches the rock is the right wheel) and get off the car. It should be swinging in the air (still poining at the objective) and with timing, explode the C4 in the car just when it's about to hit the objective (you'll need to disable the Rocket Modification, and keep in mind that the explosive's timer in cars is instant, so don't worry about delay). Try to get it in the middle of the targets, so it can blow up as many as possible.
I have no screenshots of this part because it's hard to hit F12 precisely in a 1 second period. So here's a preview of your success.

This strategy helped me get this challenge in 1 hour (counting the time I was figuring out how to do it) instead of wasting a significant part of my life in getting the perfect angle, time, speed, and whatever RNG controls the explosion points in this mission.

Some may say "Why aren't they fixing this game-breaking bug?" but, what if this is the way it's meant to be done? If they let you equip the GE-64, what if this is the only level that actually forces you to use them so you can experience a different way of doing Blast challenges? Hell, they even put a ramp-like rock right ahead of the targets, if this isn't intentional, I don't know what's a coincidence anymore.

Anyway, hope you have managed to get 5 gears on one of the most (if not the most) difficult and precise challenges on Just Cause 3!

Also, thanks to all the people that have used this guide before. I never focus on the likes of a guide, I see the views, and for me to get this amount of views and getting comments on this guide every month, thanking me for creating this, is the best gratitude you can give me.

Thanks for making me enhance this old guide,

thanks for making me reinstall this artwork of a game,

thanks, for reading. Have a great day, see ya.