See above post. The "tracer" is definitely more of the complete chassis however you can buy just the link/skid system that I am calling a subframe.
Why all the hate for subframe type builds?
- Thread starter HenikonLJ
- Start date
See above post. The "tracer" is definitely more of the complete chassis however you can buy just the link/skid system that I am calling a subframe.
This is what is being referred to as a "subframe" in this thread. Yeah, that style - to which the links get attached, with a "ramp" on the sides, with all the talk that comes with discussing that style of suspension.
Last edited:
You are not going to find much as most of the companies really do not want you to know. As for the Motobilt go to there site and look really hard at picks of their builds and then read this https://digitalworks.union.edu/cgi/viewcontent.cgi?article=1015&context=theses and it will start to make sense for you.
They can't really tell you where the roll center and antisquat will be since they're only providing the mount location for one end of each link, anyway though, so it's up to the builder to set those characteristics at thr axle end. Do they at least share the vertical and horizontal separation?
By using a few basic assumptions (like using the top of the bellhousing as the COG) they can give you some rough numbers of where things are at. Then if each of those companies followed suit then you can get some basic numbers to compare with. Just like using the link calculator if you remember to look at things from a more general point of view and not get stuck in the weeds with the numbers you can start to see things better.
Rear separation on the Motobilt at the frame is 5 3/16 IIRC and they recommend 10 inch minimum separation at the axle. This falls within the original established guidelines from the God of Suspension thread on Pirate which if you read the link I posted is the literal sum of the entire thread done as a college thesis. But the basics from all that reading is this, you want a minimum of 25% of you tires diameter for axle side separation and half of your axle side separation for your frame side. So with a 40 inch tire that gives you 10 inches at the axle which in turn means 5 inches minimum at the frame.
Black - Check my understanding here: Isn’t the required frame side vertical separation influenced by the control arm length? i.e. - longer length control arms require less vertical separation than shorter arms to achieve the same geometry?
First I have heard subframe used with a TJ.
Subframes to me means the motor and front suspension as a unit tied into a uni-body vehicle like a 67 to 69 Camaro. Heck, aint an XJ like that?
XJ's don't have a subframe, such as like what you would find on a unibody car with detachable subframe that holds the engine and trans. XJ's have a true "unibody frame". That is to say the body tub and frame are all integrated...
I don't disagree with the logic, it just isn't common to me and the folks I'm around. In fact, until this thread, I'd never considered that a bolt on belly skid with suspension mounting points inherent to it as being a subframe.
I think that is where my confusion comes from. I've considered an automotive subframe to be detachable that carries a significant portion of the drivetrain.
That's what I was taught in trade school and how it was referred to in every automotive shop and dealership I ever worked at.
THAT was college level honors Mechanical Engineering work???
Did he write more than one? Theses is plural for thesis. Glad I never had to write one.
Obviously you have to follow the first rule and that is it fits where it fits. You still have to be careful even with longer links as you can screw up your instant center and end like Rubicon Express or a four link that acts like a radius arm.
I can not speak to what kind of grade that gets you in school but it is a lot easier to read that paper than the entire God of Suspension thread.
Similar threads
