Setting up the rear

Edited: 4/1/2008 12:40:34 PM by GMracer

I got the idea down, but my situation is that the truck is just a frame right now, and clearly I need to get the CoG to get my IC and such, my question is should I just make my triangulated 4link adjustable ig: upper and lower frame mounts have a couple mounting holes similar to the prolink setup or should I weigh a truck that is similar but stock, so most likely a couple hundred pounds more and get it close? I plan on running the upper bars pointing towards the cab, and I really want to set this up to handle well, and hold it's power.

Your concern of the CoG is neglegible if you aren't trying to make the vehicle launch as best as it can. If you are trying to build a rear 4-link that will handle as best as it can, you will be better of concerning yourself with a low roll-center, minimal roll-oversteer, shorter link bars, around 8" of travel and most importantly proper bag placement and good shocks.

Well I still want it to launch good, since I'm sure I'm going to race it, so I kind of want a compromise a little of each. I will be running f9000 style shockwaves out back with 6.5" travel. So this is where I'm at a standstill at how I should set it up perfectly.

If you really want performance, don't use the shockwaves. You are going to want a shock that is more performance oriented and revalveable. Also, you should make different mounting positions for the bag that will allow you to move the bag around to change spring rates (double conyoluted parts work better for that.) If you aren't willing to spend the extra time playing with your valving and spring rates, the effort of trying to calculate your CoG and roll-centers and roll-steer is neglegible.

hmm I was talking to ART and they seemed to think for what I wanted, dual adjustable 9000s were perfect in what I was wanted. Could you explain further? And since it's not strictly drag should I just set my IC somewhere up front or should I take weigh the other truck that is close to me weight. The bags will have different mounting positions I planned on that before hand. Set up just like a prolink almost where you can move the coilover up and down.

of course if you talk to ART they are going to tell you to use shockwaves.

they are not made for handling as max said. they are adjustable but they have elementary adjustability.

cookie

Edited: 4/2/2008 10:17:38 AM by GMracer

so what are you recommending? I have very limited room back there, and I really want this to perform between the strip and the street. And the shockwaves just seemed to be ideal for an all in one performance package.

and if they aren't great for handling why do the ProTouring guys run sleeve bags and such?

The problem with trying to explain or even to build a GOOD handling car is that most of us don't know what truly good handling is. The Dodge Neon is a good handling car because the suspension design limits its travel to about 5" and so a stiffer spring and shock is used. As a by-product of this "cure" the cars handle well. The same thing happens when you use an ART kit. In order for them to make a relatively simple bag kit, the bags are smaller than they should be and thus are stiffer compared to what Detroit would have chosen for the car and have less travel. So as a by-product, the vehicle handles decent.

The "ProTouring" cars that you are seeing are typically not the performers that they appear to be. I'm sure that they will do well enough for the majority of us, but will be outrun by an equally equipped car with say Bilstein coilovers with the proper spring-rate and valving. The sleeve bags are tough to get a desirable spring rate out of because of their design. There is nowhere enough room on this forum to explain what is happening dynamically, but trust me, if it's performance and tuneability that you want don't use the Shockwaves. A double convoluted bag, mounted on the bar, with several different mounting positions and a good revalveable Bilstein shock is the key.

As for IC, something just short of the front bumper by a foot or so will help transfer more energy to the tires. Don't spend too much time worrying about IC height, just keep the link bars as close to parallel to the ground at half travel.

ok that's what I was looking to here about the IC and stuff, that is kind of what I planned but wanted to here another pro back it up. As for the bag placement I'm really lost at how I can fit this setup. I'm running 20x15s out back and being the frame is 34" outside rail to outside rail now, and running the 14bolt when aired out I have 2-3" between the center pumpkin and the rail. The lower bars would go right under the frame rail and connect similar to the SD s10 lowers, but the upper bars is where I am lost. I know I want them to triangulate towards the front, but 3" isn't giving me much room for a mount. Also now if I don't shockwaves I need to figure out how I'm going to run my bags.

Those shocks, how do they vary from the QA1 double adjustable?

If you are running out of space, I would suggest running a 3-link with a pannard bar. Also, for the best performance, keeping the bags as far to the outside of the frame is most desireable.

I don't know how the shocks rate as compared to the QA1 parts. You can call Steve at RCD and ask him. They have put a lot of different shocks on their shock dyno. He's been doing this for a LONG time and is always willing to help. (619) 328-5401 x109