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Old 02-21-2007, 10:43 AM
  #1276  
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Default drive shaft/steering rack interference

Originally Posted by trumpster1
CurveRacer - I actually used small washers under the front diff housing. It raised the entire unit enough to clear the shaft from the steering unit.
My concern with raising the diff unit was the effect of altering the front drive shaft angle.
But this is also a method of raising the front roll center (... hummm).
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Old 02-21-2007, 08:07 PM
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Originally Posted by CurveTracer
My concern with raising the diff unit was the effect of altering the front drive shaft angle.
That's what I was wondering about. On a buggy you would expect it. On a TC? No real clue
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Old 02-21-2007, 08:46 PM
  #1278  
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well that rubbing action is the one real beef i have with the kit. i was just content on letting it wear down after running it for a while but it still rubs. i may give the washer trick a try anyway. i only need a mm or two.
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Old 02-22-2007, 08:25 PM
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Default Steering rack/driveshaft interference

Thanks for the responses, I am going to find a solution for this problem. One that of course does not cost any money.
You know if this is the only interference problem we have with these cars we are lucky. Some other higher end models have problems that cause damage to spur gears, transmission one way bearings etc.
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Old 02-22-2007, 09:04 PM
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Do you guys think that the rubbing negatively affects performance when cornering and it rubs? i haven't noticed any difference between cornering on either side with it and it only happens to me if i turn the wheels left.
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Old 02-23-2007, 06:45 AM
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i think that its hard to notice during accelaration because our engines are pretty powerful. during off-power steering i know it has to have an affect because its scrubbing off some of your speed while your coasting through a turn.

how much it slows you down may be minute because we quickly jump back on throttle though.
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Old 02-23-2007, 09:14 AM
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Technically, wouldn't it only affect the rear wheels of the car off power? Since there's a one way, the front should freewheel anyway, regardless of what the driveshaft is doing.
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Old 02-23-2007, 11:48 AM
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Default Drive Shaft/ Steering shaft interference

Delta9 and spenzalii,
I have not noticed any effects during on or off power cornering. I have not noticed any ill effects on the steering either.
I used the oneway for a few races last in 2005, but swapped out the oneway for a gear diff and have run gear diffs front and rear ever since.

Nitrothug,
you're right, after a brake and short coast, we are on the throttle quickly in these cars and wouldn't notice any acceleration issues.

The only drivetrain problem I had was clutch setup related, my engagement was too harsh. This caused oversteer on some corners if I was getting on the throttle in the corner.

I will work on this problem this weekend.
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Old 02-23-2007, 03:05 PM
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Originally Posted by spenzalii
Usually what rubs is the nut for the servo saver. I replaced the nut and haven't had a problem. The only other thing I can think of is to sand that part down
I did what spenzalii did. Just replace the nut and you should be fine. I guess you can also file it sort of just to remove some metal off the nut. I'm using also the LD3 aluminum servo saver and never had any issues. This car still rips. Very rarely you see shaft drives at our track these days though.
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Old 02-23-2007, 07:00 PM
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Red face

I analyzed a couple of cars and two items are contributing to the problem.
1. the 3x12 mm screw that controls the spring tension on the servo saver when set very tight rubs the collar of the drive shaft.
Loosening up or shortening the screw to 11.5 or 11 mm. is one solution.
2. The entire assembly is a fraction of a mm too high. A thinner nut helps and the plastic will quickly get shaved down.

So we have a $0.00 solution, works for me!
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Old 02-23-2007, 09:46 PM
  #1286  
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Originally Posted by spenzalii
Technically, wouldn't it only affect the rear wheels of the car off power? Since there's a one way, the front should freewheel anyway, regardless of what the driveshaft is doing.
ahh you are right about that.
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Old 02-24-2007, 10:41 AM
  #1287  
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Default chassis setup

If you are suffering from a loose rear when entering a corner, by giving it more drupe and tow in from the rear does it helps? the track I am racing on it's technical and not that flowing!! I am using yellow springs all round, with shock oil 30, and diffs 30k front and 3k rear. Any suggestions what I can do?.

Joe F

Last edited by Joe Tanto; 03-08-2007 at 05:02 AM.
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Old 02-24-2007, 12:46 PM
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Originally Posted by Joe Tanto
If you are suffering from a loose rear when entering a corner, by giving it more drupe and tow in from the rear does it helps? the track I am racing on it's technical and not that flowing!! I am using yellow springs all round, with shock oil 30, and diffs 30k front and 3k rear. Any suggestions what I can do?

Joe F
Rear toe will mostly affect your traction under power and decelleration to a lesser degree.
Droop is a fine tuning aid, and I am not sure it will directly clear up your particular problem.

Are your front and rear shocks all the way layed down? The rear shocks need to be layed down, especially for stability.

Get your diffs equalized. Right now the rear unloads long before the front. Get the shocks oil, springs and sway bars set before running with big differences in diff fluid.

Here are my suggestions based on the components you have:

diff fluid Front 10k Rear 10k (or 3k if that is the weight you have)
shock positions - fully laid down

shock oil front 60 wt
Rear 40 wt.
Camber Front -1 deg.
Rear -2 deg.
sway bars F/R flat

Tires F 40 shore
R 40/37 shore
Ensure your roll center is in the low setting, (lower hole on the rear upper link) and work with the sway bars to get your car balanced.

Later I will post my CD3 setup.
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Old 02-24-2007, 07:43 PM
  #1289  
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Thumbs up

i was able to modify that center nut on the steering rack. i used a dremel and just shaved a little at a time. i left the same sized screw though CurveTracer because i need it to catch the remaining plastic in the thread of the nut so it does not risk backing out by itself.

while i had it apart, i also installed some teflon bearings i had laying around to replace the two bigger brass bearings in the rack. it was smooth before so i dont really notice any difference yet.

anyway, the mod cured what rubbing i had left!
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Old 02-25-2007, 01:14 PM
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That sounds like the trick there. If I remember correctly, it was th eplactic inside the locknut that was pushed upwards once the screw passed thru it that rubbed the cap joint ring on the driveshaft. A bit of filing should cure it. I had another nut from my RC Screwz kit that was about 1mm lower in profile that did the trick. With the amount of friction that was removed by switching to the ceramic bearings, I barely noticed it last year. Since I did the rebuild, I figured I may as well take care of that as well.
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