Hypotheticaly lets say that I am buitlding a 104" wheel base, light weight, full bodied rig. It has coils front and leaf's rear. The rear it too stiff and this cause some instability. I'm thinking about making a rear triangulated 4-link. With coils or coilovers. I have been tould that this is not a good idea and that rear coils are not a good thing. That they cause a rig to buck when climbing hills and caus instability in a off camber situation. I want to know what everyones ideas about control arm design (I have looked at the fix my rear steer topic) and on the performance of this setup. Not anything about cost or amount of fabracation. So let's hear it <IMG SRC="smilies/biggrin.gif" border="0">

it sound like you are talking more of a shock problem. i am a firm beliver that a spring acts like a spring if the coil/torsion/leaf springs are all of the same rate per in. thats it. they have the same reaction. but leaf springs are more of a progressive design and that may contribute to what you have heard. my self i say build it and if it doesn't work like you planned learn from it and build it better. my 2 cents mike

I wouldn't think you'd get too many takers on that theory.

Coils in the rear of my truck caused none of your listed issues, on the contrary, it was one of most beneficial upgrade's I have done to my vehicle. Period.

No matter what type of suspsension you choose, the ultimate performance you derive from it will be based upon how well it was designed and executed

Bad design=bad results. That goes for coils, coilovers, 1/4 elliptic or otherwise.

Tim.

A well desinged and built coil suspension will work extremly well. The main benifit is no axle wrap. The bucking can be fixed with properly valved shocks. Any problems with stability can be partially solved with proper spring rate and something to hold the coil in its seats at all times.

Originally posted by gunracer1:
<STRONG>I am a firm beliver that a spring acts like a spring if the coil/torsion/leaf springs are all of the same rate per in. thats it. they have the same reaction.</STRONG>
I agree with you, springs all do the same thing. I can get progressive coils so that isnt a factor. The reason I want coils is because they can droop and the spring itself dosent limit the flex. I dont think I will have problems with sidehilling because the front and rear will be very balanced. I think that balance is more important than type of spring for off camber situations. I pritty much have my mind set on the rear coils. I'm goign to be useing this setup on a 2 door XJ. It will be easier to pull off that 1/4 elip. I just wantend to see how many people I will be proveing wrong about F&R spring preformance <IMG SRC="smilies/biggrin.gif" border="0">

How's this sound: 2 door XJ, lot's of chassis stiffining (Cage, trussing ect.), 4 link rear w/D44, matching D44 front maybe useing the skycracker RR arms, Coilover's, lots of trimming. I'm also thinking about covering/replaceing all the sheet metal below the windows with thicker stright pannels and making front fenders framed with schedule 40 pipe. I say sch. 40 caus its not going to be structural. The suspension is being designed to ride low (5.5"+stock) but have lots of droop, keeping the CG low but have high flex. I guess JP was right about the ultimate XJ buildup this is starting to sound alot like it. hope to start this winter. I need to find a 2 door. <IMG SRC="smilies/biggrin.gif" border="0">