Rocket stiff like a wagon in the back..outta things to check HELP

[17m fan]

02 black front
Penske non adjustable non canister w/ coil over kits 4 races old
new Hyperco 12" 200 LR/225 RR
bird cages all free not bent no tight spots
rods are parallel to each other
all rods straight, right length & good joints
correct ride height
lift bar straight & level
lift bar locating rod straight, right length, good ends
5th coil good in farthest hole back
pinion angle @7 degrees
LR axle pulled
J bar good
drive shaft not bottomed out
nothing that moves in the back is making contact with anything else anywhere.
Every individual piece works as it should by itself but when all together its near rock solid when pressed down on...travel indicator show roughly 1/4" only when its bounced.

I have a little theory that may be way out in left field but...I am on 12" springs in the back. 200 LR 225 RR...Could it be entirely possible that in order to make ride height (8 1/8" axle tube to frame) that I am having to turn the adjusters down so far that it is causing coil bind?

Need ideas cause we're all out.

[17m fan]

Pretty much throw the coil bind theory out because the RR spring is compressed only an inch at ride height.
The lateral location of the rear end is now off by about 3/4" to far to the left. My adjustment to the bar has always been close to being maxed out (3-4 threads) but now, it's adjusted as short as I can make it and it's not enough, which tells me something has the car held up

[fox1162002]

What bird cages do you have my 02 is no where near those ride heights. I wanna say mine are 6 5\8 have to look in my book.

[jedclampit]

First 4-link car?
Aluminum liner type cages?
Where do you have the link rods on the chassis?
Also what is the height of the PH bar center @ frame?

Put an angle finder on the lower links with the lower rods in second hole up from bottom on both sides and report back.Top rods in middle holes @ frame.
RR lower should be level/0* to 2*(max) uphill towards front with correct ride height.
If it is more your rr ride height is too high.
I'd bet it's either a bent or dented shock, or ph bar too high on frame.
A few pictures may reveal something.

[drtrkr244]

according to the Rocket set up book, your RR ride height should be 5 5/8 from bottom of framerail to top of bushing on birdcage. LR should be 1/2 to 3/4" higher. The lateral location of rearend should be 16 1/2", from inside right framerail to the outside of the 90/10 plate.

[fox1162002]

Mine is 5 5\8 RR ride height. RR top center hole RR bottom center hole. J bar is 9" from center hole mount to bottom of frame. Bottom @ pinion. If you got 8 1\8" of ride height your way to high the rear will be stiff. RR bottom bar on my 02 rocket @ ride height is 0° 2nd hole from bottom.

[PenskeShocks]

I would recommend giving James Stevens from JDS a call. Awesome with shocks, and car set-up. Where did you get the shocks from. I doubt it is all shocks, but if we get a bit more background, i am sure we can help.610-375-6180 ask for Aaron, he will forward you onto James.

[17m fan]

Yes it's 4 bar car. Rods in neutral holes for scaling. RR lower is between 0&1 on my angle finder. I sent email with pics of my cages to rocket about what the correct height should be with what I am using. They are the nylon lined type and they replied with 8 1/8" frame to axle tube... Not to top of cage.. Which I had been using the 6 5/8 RR and 1/2" higher LR which turns out was 1" too low from what I had been using.
I run my j bar at 9 1/4" on frame bottom hole on pinion
RR bottom between 0 & 1 degrees
Have a simple gauge that I made that's 16 1/2" to easily check the side to side location of the rear end. Switched some shocks around and no matter what's on it, it's bad stiff.
So I have ruled the shocks out.
Here's my thoughts now something in the LR birdcage or possibly a bent LR tube. Here's why....
If the cage is bound up on top of the tube with weight on it, at ride height,it's going to hold the rear end to the left. Secondly, with a jack under the seat, the tire just off the ground, the tire comes visually straight up. Reference marks on the cage show only 7/16" forward roll. And thirdly, since the car is 1/2" higher on the LR, if it's bound on top, when it's bounced down on, the LR cage is what gets pressure 1st. Therefore making it feel solid across the back.
I have measured between the cages to both the rotors and side of the rear end any place I can get a good read on and it all checks out good.... Unless, the tube is bent some direction up inside the housing, it has got to be that cage. I've eliminated everything else I can think of.

[zeke23z]

I have a set of the lined rocket cages if your interested.Been sitting on a shelf for a couple years and need cleaning but there in working order.$100

[7uptruckracer]

How much LR drop do you get before it lifts the tire up? Disconnect everything and spin your cages, do you bars run straight, can you turn your tubes on the heims with everything attached. What length is your stabilizer bar for the lift arm? Make sure lift arm isn't hanging up at the front on the X brace, disconnect everything and get two jacks and jack the car through travel and let it hang etc. I chased one all week and it did turn out to be a problem in my driveline, just because it looks ok take it all apart and check it piece by piece. What is your trans? Center to Center shaft Length and slip yoke length. There is a early gen Bert trans that doesn't have deep splines on the shaft so everything can look right but it definitely won't be right!!!! Learned from experience

[17m fan]

When everything is disconnected, everything is fine. The bars are run straight visually and checked for straightness. The cages spin free. The tubes turn free when hooked up, The stabilizer bar is I think 13 3/4...it's whatever the book says. The lift arm is not hitting the x brace when cycled....Its close some where around 3/4" but not hitting. I been all through the drive line and its good. And even have it out now to eliminate that possibility. Using Brinn transmission, 6" yoke. I don't remember the shaft length right off.
We put the car on stands and unhooked the 5th coil and cycled the suspension with the lift bar, looking for binds etc and its all working right. Put all together, set it on the ground and its like a go kart in the back again.

[7uptruckracer]

You can check your camber on your tubes or just do measurements to your bell. The lateral location isn't really meaning much depends if you have the right jbar and jbar mount so confirm with that. If your ride heights are right then there is no bind that will hold your rear end in the wrong location laterally thats a static setting issue. I ran into this before. can you get 45* in your upper on there abouts at full drop? How much does RR travel in race?

When everything is disconnected, everything is fine. The bars are run straight visually and checked for straightness. The cages spin free. The tubes turn free when hooked up, The stabilizer bar is I think 13 3/4...it's whatever the book says. The lift arm is not hitting the x brace when cycled....Its close some where around 3/4" but not hitting. I been all through the drive line and its good. And even have it out now to eliminate that possibility. Using Brinn transmission, 6" yoke. I don't remember the shaft length right off.
We put the car on stands and unhooked the 5th coil and cycled the suspension with the lift bar, looking for binds etc and its all working right. Put all together, set it on the ground and its like a go kart in the back again.

[ConleyRacing18]

See how much slop is in your birdcage to the tube. I had a similar problem. When in the garage they seemed free, but with weight on them they would rock over and the bolts on the brackets were hitting. I put in new liners and spacers between the birdcages and the ends. Problem was solved.

[ConleyRacing18]

Unless the ride heights changed between 2002 and 2003 they seem too high. Have to measure my stick.

[HuckleberryB4]

Had the exact same problem as Conley!