Cool Under-Car Video....Added 2nd Video 10-10-11

Thanks to Keith Fulp for the use of his camera. We were very pressed for time to get the camera mounted and ended up clamping it to the wheelie bar, which was not the most stable of places but, still gave an excellent angle to view the shock. This was a great way to see exactly what is happening during a pass. After watching the video, it appears that my left rear wheel is bent just a touch or, possibly the tire is at fault....which is probably the vibration I've been trying to find for a couple of months now. Left lane at Windy Hollow.
https://www.youtube.com/watch?v=O-ukK3jrYr8

2nd Video...
This is a time shot from last Saturday at Muncie. Thanks to Tracy Smart for the use of his camera. The shocks are 2 clicks tighter on the hit and, the same on the bump as the first video.
The track was pretty good and the car was dead-hooking every shot. This is a 5.83 @ 119 pass. 1.27 60'.
I'm going to try about a 1/2# more air next weekend...looks to be killin' the tire just a touch. This video really shows how "tweaked" my wheels are getting. Maybe Santa will bring me a set.
https://youtu.be/5_JrPUFk6p8

damn.....i realy wish i coulda done that. maybe next time.the slowmo realy shows the beating your shit takes.

Damn good shock/suspension video.

Attaching the camera to the wheelie bars (vs the frame) was probably a better idea anyway on your car since you have the "up-side-down" shocks. Mounting the camera this way gave a better view of the shock air gap/motion cuz it's better to attach the camera to which ever end (suspension vs frame) has the air gap. Top air gap = frame mount camera, bottom air gap = housing/wheelie bar mount camera.

The wheel/tire wobble could also be from a slightly bent axle flange. It doesn't take too much runout at the small OD axle flange to create a noticeable amount of wobble out at the bigger OD slick.

Is it a ladder bar or 4-link? It looks to have a decent amount of suspension separation at the initial hit. Was this a throttle-stop launch with fairly loose extension valving, or an all-balls launch with tighter extension?

X2 on the possibility of a bent axle flange. I thought I could hear a noise in your brakes while you were slowing down. Just went through the same thing with my buddy's Camaro, rear wheel / tire wobble. One guy tells him it's a broken belt in the radial tire, another tells him its a bent wheel. I put it on jack stands, took the wheel off, ran the lug nuts back on, and watched it while it idled in gear, the edge of the brake rotor was wobbling about .030. We finally traced it to a bent axle flange. It didn't seem like much at the axle, but it sure made a big difference at the edge of the tire. We finally found out that the previous owner broadsided a curb on a snowy day.

Wayne (SAWDOFF) Pearce

Hey Jeff, want a Burrito???!!!

one of my old weld prostars had a tweak in it and it wobbled pretty bad.

DILLIGASDAVE wrote:Is it a ladder bar or 4-link? It looks to have a decent amount of suspension separation at the initial hit. Was this a throttle-stop launch with fairly loose extension valving, or an all-balls launch with tighter extension?

The car is a ladder bar deal. The hit was set at 2 clicks from full-soft and the bump was set 5 clicks from full tight. For this particular pass, it was not a good set-up for the track conditions.....it was moving around quite a bit.
After a quick look at the video on Keith's lap-top, I tightened up the hit 2 clicks, loosened up the bump 2 clicks and, changed lanes to the right lane.
It didn't make much difference at the hit but, helped the car get down the track much better.

The axles were brand new Moser 35-spline at the beginning of the 2010 season....I have not checked them for runout yet but, if the problem IS the axles, they are under warranty.
I'm thinking the vintage 1994 Weld wheels may be the problem....lol. They have been hit hard a few times.

crittersf1 wrote: Hey Jeff, want a Burrito???!!!

I think the burrito was not to blame....as much as the Crown Royal and Coors was.....lmao.
But, hell yes, them damn burritos were good.

That's what I thought

Burritos......what Burritos??? I guess I missed out on the good stuff...

Treeyasoon wrote:Thanks to Keith Fulp for the use of his camera. We were very pressed for time to get the camera mounted and ended up clamping it to the wheelie bar, which was not the most stable of places but, still gave an excellent angle to view the shock. This was a great way to see exactly what is happening during a pass. After watching the video, it appears that my left rear wheel is bent just a touch or, possibly the tire is at fault....which is probably the vibration I've been trying to find for a couple of months now. Left lane at Windy Hollow.
https://www.youtube.com/watch?v=O-ukK3jrYr8

Yeah...it would have been good to plan a little better and mount the camera nicely, but for a last minute deal, it turned out OK. It was one of my little Oregon Scientific self-contained sports cameras. Due to the waterproofing, they do not have very good audio, but the lens and performance make it killer for under car.
Thanks,
Keith

Thats a good shot there, are those goodyears if so its the tires, if not wheels.
The track last was bad I tought did your car skate around? Miine moved after 60 ft bad.

Real busy back there ain't it?

crittersf1 wrote: Real busy back there ain't it?

We ought to hang one of those on your mud truck! It would be cool until it got coated with goo...or knocked off!

What spring rate are you running on the rear shocks?
Gary

GTmustang wrote:What spring rate are you running on the rear shocks?
Gary

They are 115# Af-Coils.

Treeyasoon wrote:

GTmustang wrote:What spring rate are you running on the rear shocks?
Gary

They are 115# Af-Coils.

Thanks for the info, it looked from the video that they must have been a fairly light spring. I'm also running 115's in the rear, but I saved my old 130's in case they don't work out.
Gary

Added a 2nd video.