Rustler nosediving more then the recommendedd daily amount...

[T3rox]

hey guys,

Thanks to all you guys who helped make my T3 run HOT! now, when i race my freind, or my sister's rustler... its rather a laughing matter. But, i feel like i'm being unfair here, because my sister's Rustler has a horrible problem with nosediving...

I recently made a small table top for my T3, 30 degree take off ramp that is about 12" tall at its apex. I Can wind the T3 to its top speed, hit that thing and pull heavenly air, using the Throttle to correct my attitude and landing on the tires every time. My sister's rustler nose dives SO bad it doesn't even land on its fron tires, it lands on the front bumper instead, and she's new to the sport, so usually doesn't hit the jump quite square, and hits the ground on ONE WHEEL standing on the nose I'm quite certain that ain't good for it... care to speculate :) ?!?

[RCJunkie]

Does she keep the throttle on in mid air? That's how you keep the nose up. If she lets of the gas or brkes the nose wil go straight into the ground. Maybe also try some heavier oil in the front shocks. If the suspension if compressing fully when the car hits the jump it can affect the take-off.

[jeepinator]

Contrary to popular belief, heavier dampening in the REAR will reduce nose diving. What happens it the rear "slaps" the ground just before air time causing the rear to bounce up.
The shape of the jump has more to do with it than anything however. If my goal is max air (for fun), I tune the jump way more than I tune my car. A smoothly progressing jump usually produces the best jumps. Make sure there is no "lip" at the end of the ramp.
Also, make sure the car is not getting air just before the jump (you can test by looking carefully at the tire tracks). You want a smooth ZZZZZIP effect.

Heheh, the science of air time, by jeepinator :rolleyes:

[JP]

OK, tell whoever is driving it to let off the throttle right before the jump (about 4-6 feet) then gas is right when the front tires hit the jump, thats the cheapest method to stopping it. You can also stiffen the front springs, soften the rear, and add more downforce to the rear of the body of the truck.

[ 04-28-2001: Message edited by: JP ]

[jeepinator]

A few years ago I set up a camcorder with a 1/1000 shutter capability next to a few jumps (beside them) and then recorded zillions of jumps.
Later that day I watched the entire tape a few times, stepping through each frame individualy.
I am telling you that the problem of nose diving is due to the rear being TOO SOFT. Softening the rear damnping will exacerbate the problem, not aleviate it.
The rear of the chassis slams on the ground prior to the end of the jump. This causes the rear of the chassis to move upwards very rapidly (kinda like a bounce, I guess). It isn't that the nose is diving per se, it is that the rear is flying ;)
Another cause in air attitude problems is what I call "pre-jumping". If the jump is not perfectly progressive the car will leave the surface prior to the highest point of the jump. I witnessed this time and time again at local races with my camcorder. The jump must be shaped with an increasing angle to fully utilize the height of the jump itself.
Pre-jumping also makes for upredictable suspension tuning. In some cases the car will do a little hop then slam into the face of the main part of the jump, causing severe stress on the suspension and resulting in wigged out in-air performance.
A poor mans way of tuning a jump is to brush the jump with a broom. Make the surface have a distinct pattern. Then jump your vehicle just once and inspect the tire tracks left behind. You will be amazed to see most jumps are built in a way that the car leaves the ground (much) prior to the end of the jump.
A perfect jump will cause your car to make a "zip" sound as you travel up the face. It is a hard to explain sound, but it is a very satisfying :) If you have a nitro rig them bummer for you, you won't get to hear it ! ;)

EDIT: Oh, and BTW, the "punch it just before the jump" tip is a good one. This is how you compensate for less than perfect jumps, or to get serious distance out of almost any jump.

[ 04-30-2001: Message edited by: jeepinator ]

[noobie]

again, i have to back up jeepinator! stiffen the rear! and of course the throttle control issue is the most important.

[Railman]

Sounds good to me too Jeep. Another isue with nose diving is having way more dampening in the front than the rear, Once the truck is in the air the rear wheels can snap out faster than the front, causing a recoil effect, & lifting the rear. You need balance front to rear on dampening. It all depends on the jump though, one fix doesn't fix them all. Anyone thats ever had one shock thats low on oil knows what can happen with uneven dampening! If you drop your truck from about 1 ft the front & rear should settle at the same time to be balanced front to rear. There could also be a problem with weight distibution front to rear (too heavy in front), but thats unlikely. Good luck.

[JP]

Thats kinda funny Jeep. I set-up a ramp with progressive amount of curve to jump my GT. And found the same thing, that stiffening the rear helps nosediving (saw scratches on the wood from my chassis scraping. But what I assume on most of these cases, is that the jump is not angled, and not steep. I whole-heartedly agree, to a certain extent. All jumps are different, even if they're manufactuered the same, or built the same. Which is why I want to help my track make the jumps (ill test it myself, i dont care), having the racers MAKE and TEST the jumps, makes a track all that better because we can angle the jumps to out liking, so the jump is actually used. We can also assume taht usually the jumps most people with problems make are small, flat, slow speeds, and very little angle, which is usually why you would want to soften the rear. See where im coming from? I have a great picture of my GT bottoming out as soon as the front tires hit the jump, especially considering the jump was very steep and angled, in fact, the chassis looks all bent because of it. I will DEFINATELY post it as soon as I get a scanner, because this is a VERY clear pic of what happens when the car hits the jump.

[gubbs3]

To keep the rear end down either go to a stiffer spring in front or a thicker oil in the back. Its mostly about bounce, if the front doesn't get as high as the front then the rear has more "bounce" to it than the front. I'm saying "bounce" refering to how much the suspension pushes the car upwards from being compressed by the jump face. So to get less bounce out of the rear, take steps to make the rear end not move as fast or to make the front move faster. I think I lost myself typing this but I hope you get my idea.

[XXXER]

To get nose diving out, you stiffen the FRONT springs, when they are nose diving, it is because the rear are too stiff, and not absorbing the jump, whereas the front of the car is, so you go to a lighter spring out back, or thicker oil, or a stiffer spring in the front, or lighter oil out front.

[Nairb]

I think most of us beg to differ in this situation, Steve.

[jeepinator]

Let's just say that there could be many solutions, mostly depending on the unique circumstance you may be in.
I posted my experiences. Clearly what works for one person may not work for another. I should have worded my response to that effect instead of sounding like my solution was the final word.
I do, however, have very good evidence to support my opinion.
Each jump is unique. Each person's setup is nearly unique. This makes it very difficult to answer the original question.
Again, in most cases, for me personaly, doing whatever it takes to keep the rear end from slapping the face of the jump will stop the "nose dive" problem.
I think most of us are in agreement here though, right ? :p

happy jumping