Preperations for 70+ mph run?
#1
Preperations for 70+ mph run?
My friends and I all have Rustler VXL's and were talking about getting a speed run in we just wanted to get some advice before we attempt it. So far from what I gather we should:
- Use softer springs (red traxxas)
- Lower the ride height on the A-arms
- Put 60wt fluid in the shocks
- Flip the RPM bumper over to push the air over the car instead of under it
- Put the wheelie bar on
- Tape up the underside to prevent air from getting under it and flipping it??
Any other suggestions would be great, we have never done this before so any tips are appreciated.
- Use softer springs (red traxxas)
- Lower the ride height on the A-arms
- Put 60wt fluid in the shocks
- Flip the RPM bumper over to push the air over the car instead of under it
- Put the wheelie bar on
- Tape up the underside to prevent air from getting under it and flipping it??
Any other suggestions would be great, we have never done this before so any tips are appreciated.
#2
Tech Adept
iTrader: (6)
Now my understanding of aerodynamics is not complete, but I would think you would want air underneath the car - specifically, air moving faster than the air over the top of the car as the lower pressure underneath will keep the car down...
All I need to know about aerodynamics, I learned from Mr. Wizard...
All I need to know about aerodynamics, I learned from Mr. Wizard...
#3
Sounds like you are on the right track. Oh yeah, make sure your on the right track, literally. Wide open parking lots are a must. I have attempted speed runs on very wide streets and still not enough room. When you start using that much power everything is amplified big time. Glitches show up you never had before, and the time to correct imperfections in your driving line disappears. Double check all the tires to make sure they are glued well, and balancing them would not hurt either. Also remember those tires likely wont hold up to very many 70MPH runs. Im sure these are things you may have thought of already, but hopefully we can help anyone else wanting to do speed runs.
#4
Check out www.rc-isc.com, all you need, they will help. Nic Case (current world speed holder) is an admin on there.
#5
Tech Elite
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Correct, you want more air going over the car than under it. This creates low pressure underneath, which pulls it down.
And you'll have a hard job getting over 65, a guy over here in the UK tried, and even with a MM 7700 on 3s struggled to get 65.
And you'll have a hard job getting over 65, a guy over here in the UK tried, and even with a MM 7700 on 3s struggled to get 65.
#6
Tech Adept
Definitely come check out RC-ISC and its forum (I am a member over there) as there are a couple other Rustler projects going on that have some good info in their threads.
#7
Well we ended up running the cars last Friday but only got up to about 54 MPH (according to the radar gun). I blame it on bad winds and lack of space, we did it at a police skid pad that is near us but ended up not being long enough. My other friend brought a ramp out though and they ended up launching the cars to see how far they could go......yea....they went ~65 feet. I was amazed they didn't break any parts, only bent one shock shaft...anyhow thanks for the tips guys we are going to try and get faster than 60 at least.
#8
Tech Master
iTrader: (16)
I hit 61.7 in a Stampede loaded with a mm7700, 10 cells (6 more under chassis) and a 4oz Garmin GPS seen here.
One suggestion...front end weight. The RPM bumper is a sail at high speed...dont know about upside down, I'd remove it completely and drive it carefully. Also, I had the Garmin strapped to the front, I had an earlier incident where I flipped over backward on a 50 mph wheely. Added weight and problem solved. Good luck...and bring parts.
One suggestion...front end weight. The RPM bumper is a sail at high speed...dont know about upside down, I'd remove it completely and drive it carefully. Also, I had the Garmin strapped to the front, I had an earlier incident where I flipped over backward on a 50 mph wheely. Added weight and problem solved. Good luck...and bring parts.