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musolino21
05-12-2019, 08:51 PM
What are reasons why a car won’t stay hiked up? I’m having issues with the car falling off the bars on corner exit and straightaways and makes the car walk left and right on the straights.

Note:
- I have a soft Lr spring for hike up.
- Soft rf spring
- I have suffient rebound in rf shock
- All other shocks are set correct on comp/reb/pressures from my shock builder
- My ballast is at a height where I never had issues with weight transfer.
- I’m at 13.9375” - 14” left rear drop
- Same driveline from what was run last year
- 54.4% Left, 53.8% Rear, 100# Bite
- All new heims
- Panhard is 8.75” on frame, bottom on pinion (never had an issue at that location and had success)

What else could be binding? Could the car settling back down be an issue with pinion angle, rear alignment, lift bar?

musolino21
05-12-2019, 08:59 PM
Bumpsteer and front toe was checked and set as well.

billetbirdcage
05-12-2019, 09:36 PM
Bumpsteer and front toe was checked and set as well.

Tony, what car you in now? if you still got my number just call me

Jking24
05-13-2019, 05:34 AM
First what billet said. If you don't. Are you sure it's ever getting all the way up and falling or is it just not getting their at all. I know you say it's the same but i would check the drive shaft engagement on the trans if it's a traditional slip yoke if it's a ball spline then i would inspect that thoroughly as they have caused this many times. Other areas are your bird cage bearings aswell as your fifth coil

musolino21
05-13-2019, 06:42 AM
It’s a 2014 Blue/Gray. Billet, I have your phone number, I sent you a pm and I’ll call you later today. Thank you.

jking24, we have a few videos and studying photos the car is getting on the bars in the turns and then falling on the straights. Thank you for the input about the yoke/ball spline, I will look into that.

JustAddDirt
05-16-2019, 07:49 AM
what heims did you put on?
that could be your binding issue.

Racerguy27
05-16-2019, 07:32 PM
How would the ballspline cause this.

Jking24
05-16-2019, 07:39 PM
How would the ballspline cause this.They basically bind up and act just like a driveshaft that is too long. If you remember last year when peirce first got in the rocket they were really struggling the first few nights. It was their transmission causing it. It prevents the car from getting all the way up on the bars. I've also seen them let the car travel the full distance but be resistive and cause the car to have a major lack of traction

LRtireCHANGER
05-16-2019, 08:24 PM
Sometimes a rear end waggle can be caused by inconsistent traction at the real wheals. This happens when the car hits a slick patch, and one of the rear wheels looses traction for a slight moment, and then that rear wheel rises back up on the bars. What is happening is one of the rear wheels is going up and down, causing a change in rear steer as well as a quick change in traction at that wheel. Are u sure that u have enough lr compression rate, as well as enough rr extension rate?

Matt49
05-17-2019, 08:30 AM
Sometimes a rear end waggle can be caused by inconsistent traction at the real wheals. This happens when the car hits a slick patch, and one of the rear wheels looses traction for a slight moment, and then that rear wheel rises back up on the bars. What is happening is one of the rear wheels is going up and down, causing a change in rear steer as well as a quick change in traction at that wheel. Are u sure that u have enough lr compression rate, as well as enough rr extension rate?

Excellent point. The OP should carefully inspect all axle splines, drive plates, and spool for damage. Chatter in the drive line on one side or the other could cause some strange problems like this.