FYI: At that speed, wind resistance becomes more of a factor. Unfortunately, it is quite difficult to figure that since there are so many variables. So, expect a speed a bit less than that.

Probably if you run the truck indoor with grippy floor you might achieve that speed easily.

What would I enter into that speed calculater for a revo with stock diff.s, an e-maxx tranny with stock two-speed, geared 70/12, and 70/13, and an hv6.5. Also with an hv4.5? I'm mainly concerned what to put for the diff.s and tranny, I don't know stock gear ratios, and am no good at calculating gear ratios.

There are drop-down boxes that let you select some preset values.

For the diff, just use the drop-down box and click on the Revo. It'll fill in the correct value.

Same thing for the tranny. Use the next drop-down and select the emaxx tranny. There are two entries; one for first gear, one for second gear. You probably want to pick 2nd gear. Again, it will fill in the right value.

For the spur/pinion, just enter the tooth counts in the appropriate boxes.

The same goes for the voltage. You can either type in the value, or use the two boxes and pick the values and it will do the work.

The motor drop-down has a bunch of different motors to choose from. When selected, the correct kv rating will automatically be filled in. If you know some of the kv values of the various HV motors, let me know and I'll add them to the listing.

If you make some obvious mistakes, the program will most likely let you know. I've built in error trapping and warnings when possible. BTW: if you have any ideas to make it better or more user-friendly, please let me know!

Wow, that's great. Don't remember the kv ratings right now, but I can find them and get them to you, probably tomorrow. I'm studyin' for a physics exam right now :(

The kv rating on the 6.5 is close to 4400, and is what it used to be rated, but has since been changed a little bit, and the kv rating on the 4.5 I believe is 4800. When I enter these along with 16.8 volts, it tells me that this combination is unsafe, and will result in motor overheating.

lol, tells me I'll get about 47 mph with my 6.5, and just over 50 with the 4.5. These are not accurate results for these motors :(. The 6.5 theoretically should give me just shy of 40 mph, if not dead on it, and the 4.5 in the mid 40's.

I refigured with the kv rating of the 6.5 set at 4000 kv, because I think that is close to the updated rating, and that yielded a more accurate result, about 40 mph. That still puzzles me about the 4.5 though, I saw it listed at 4800kv today.

Good luck on the test!

I told ya 60 mph was possible! :)

I certainly did not spend all the money that I spent to only go 40-45 mph. I it hits 55-60 mph I'll be happy. Over 60 mph is gravy.

With that kind of power your going to have some tire growth. Kind of like a dragster which will add a few mph. Keep us filled in on your top speed tests:018: If you need more speed and your not running hot take the pinion up a tooth or two.