Suspension and Chassis Questions about your suspension? Need chassis advice?

Ladder bars with lower conrol arm

Thread Tools
 
Search this Thread
 
Old Jun 8, 2014 | 07:07 PM
  #1  
lugnut's Avatar
Thread Starter
Member
iTrader: (1)
 
Joined: Feb 2002
Posts: 110
Likes: 1
From: Ohio
Car: 1970 chevelle
Engine: Lq4 408
Transmission: th400
Axle/Gears: 3:73
Ladder bars with lower conrol arm

Hey guys,

I bought this drag car 85 z,and it came with ladder bars,although the guy didn't finish project,he had them welded to the floor with a bracket
It didn't look very safe to me,he also still had lower control arms on
I redid them using a tube cross member with the brackets welded to the sub frame connectors I didn't have to cut the floor,but the top hole is not accessable I then installed a 8 point cage and welded the door bars to the frame connectors,the rear hoop is on a 6x6 plates,as is the rear bars
He had stock lower control arms,so I bought tube and installed them I also have tube adj panhard bar But I don't think I needed the lower control arms with ladder bars Seem to 60ft pretty good 1.58 is the best on old slicks
But after looking at some setups here I noticed no lower control arms on ladder bar cars Im I defeated the purpose of them by putting it in a bind

Just wanted to know if I can take them off and be safe
Thanks
Reply
Old Jun 8, 2014 | 09:34 PM
  #2  
AlkyIROC's Avatar
Moderator
25 Year Member
Liked
 
Joined: Jul 1999
Posts: 17,265
Likes: 168
From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: Ladder bars with lower conrol arm

I can't see how having ladder bars and the LCA would work without the suspension binding. The ladder bars and LCA would rotate on completely different arcs. Think of ladder bars like a hinge. It's mounted at the front on a pivot and solid at the diff. The diff would rotate on the arc of the front mount and the pinion angle changes through that arc. The LCA would bind through that arc providing it allows the diff to pivot at all.

With a torque arm, as the diff pivots through an arc, the front of the torque arm has some way to expand and retract at the front mounting point. OEM uses a rubber mount that the torque arm slides through. Aftermarket uses some sort of slip link design so the length of the torque arm changes.

If you remove the ladder bars, you'll need to put a torque arm back on. There's nothing to keep the diff from wrapping around itself without either.

Is the panhard bar still in place? Something needs to keep the diff from moving side to side. Panhard bar, diagonal link, wishbone etc.

Many years ago, I installed ladder bars under my car as an easy way to install a 9". I used the LCA to keep the diff aligned until the ladder bars were in place then removed them. I still used a panhard bar instead of putting in a diagonal link and it worked fine. To allow adjustments, I boxed around the front mounts inside the car and made sections through the floor for the ladder bar to pass through. Looked ugly on the inside but I had no rear seats and it was a race car so I didn't care. The car is now a complete back half with a 4-link so I have much more adjustability than what ladder bars could offer.
Reply
Old Jun 9, 2014 | 04:43 AM
  #3  
lugnut's Avatar
Thread Starter
Member
iTrader: (1)
 
Joined: Feb 2002
Posts: 110
Likes: 1
From: Ohio
Car: 1970 chevelle
Engine: Lq4 408
Transmission: th400
Axle/Gears: 3:73
Re: Ladder bars with lower conrol arm

Thanks a lot I don't want to remove the ladder bars so I can remove the lower control arms? I thought I didn't need them with ladder,because thye r now supporting rear end Yes I do have pan hard bar,that will stay
Reply
Old Jun 12, 2014 | 12:00 PM
  #4  
articwhiteZ's Avatar
Supreme Member
15 Year Member
iTrader: (56)
 
Joined: Sep 2009
Posts: 3,776
Likes: 101
From: Spokane WA
Car: 92 Lingenfelter Z28 articwhite
Engine: Aluminum 615BBC
Transmission: Th400wbrake/curri entps9" locker
Axle/Gears: 4.11/4.30/4.56
Re: Ladder bars with lower conrol arm

Do you know the make of the ladder bars?
Or have a pic?

I have ladder bars on my car..and the maker of them says to keep your lower control arms in place. With ladder bars the rotation of the rear is almost nothing if/when your pinion angle is set.and move very little. And your lower control arms are free to move more so then you're ladder bars would ever move...the ladder bars have less movement in them.they plant your rear end..one of the largest manufacturer of ladder bars suspension parts.... Lakewood. Even with their ladderbars tell you to leave the control arms / trailing arms in place. I have had a ladder bars on my car for over 20 years with no binding ever. So I would have to ask who the manufacturer is off the ladder bars that are on your 3rd gen Camaro..because the only two manufacturers of ladder bars that I've ever used.on a 3rd gen Southside machine. and Lakewood.say to leave your lower control arms trailing arms in place....one example.. Is your ladder bars set your pinion angle... Not your control arms .your control arms will always have more free movement at each of there ends when your ladder bars ever will......

your factory torque arm has no pivot joints in it. Just a chunk of rubber in a clamshell mount. At the tale of transmission. And it is bolted solid to the rear end. And your lower control arms still pivot freely at each one of their ends....yes it still movies because it's sloppy by ladderbar standards.
unfortunately your ladder bar on the street makes for a little rough a ride only if you're going through dips and corners with dips....on my car the rear suspension can move up and down about 6 inches with no binding with the lower control arms. 6 inches is a lot that would be like Dukes of Hazzard driving but in all reality it only moves 3 to 4 inches with a dip in the road. Still not enough to create binding on my car anyway. I think this is where a lot of people I get the impression that it would bind because of the Ark of it going up or down..

On cars with stock width rear ends the control arms stabilize the outer ends of the axle tube that's all. Most the time you see ladder bars on race cars their reaends are narrowed.and the axel tubes don't sit too far out from the ladder bars. (unless your looking at old gasser race cars)

but I for one would like to see pictures of what you have going on under your car sounds interesting

Last edited by articwhiteZ; Jun 12, 2014 at 10:39 PM.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
morrow
Suspension and Chassis
78
Jan 13, 2024 12:29 PM
J-money
Suspension and Chassis
15
Jan 4, 2019 09:45 AM
Nick McCardle
Firebirds for Sale
1
Sep 10, 2015 08:36 PM
rudolphschenker
Transmissions and Drivetrain
1
Sep 4, 2015 02:41 AM
1Aauto
Sponsored Vendors
0
Sep 2, 2015 01:35 PM




All times are GMT -5. The time now is 12:03 AM.