Fifty
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This colorado in stock form has a pretty stiff way bar...well, let me go back. It has street suspension. A shoddy over priced, great idea, poorly implemented shock (that dssv) and really really really stiff springs for what it is. The truck is 4745 lbs and I think about 55% of that is on the front. (all guessing)
The front suspension uses a 14 inch freelength spring, and uses 2 inches of preload. There are two spring rates available: 550 lbs and 687 lbs (gas vs diesel truck). The 687# spring raises the front about 2/3rds an inch, but makes the front skip at speed.
The shock is a 7 inch travel and the tire moves about 8.6 inches (baller I know)
This truck, like most production vehicles, does not articulate very well in the front. So taking off the stock sway bar helps a bit, but it still just doesnt compress that easy without significant chassis movement. Now on the flip side, there is a little more than wanted amount of body roll when driving.
I have front bumps and when they have 80 psi there doesnt seem to be any change in body roll. Up that to 100-115 psi and the trucks body roll is perfect. I have 16mm air gap of oil in the bumps.
So the stock bar is too stiff. The 687 # spring is too stiff, running bumps over 80 psi is out because it makes the truck skip off road and when you G out it almost launches the truck back into the air.
If I fabricate some sort of "nascar" style sway bar, like a blade bar; how do I calculate the what stiffness or weight rating that I design into the new sway bar?
I assume I would be trying to chase down that 80 to 115 psi effective spring rate? That seems pretty light to me. I can get the math done and calculate the thickness of the main torsion bar and the design of the arms. But what magic number I want to be shooting for in "strength" or "spring rate" of the sway bar is the question. I definitely want to get pretty close to what I need and design an adjustable blade to fine tune it. But I'd like to start off close.
(And then I get to rip it all off and sell it next summer when the stock stuff gets replaced)
The front suspension uses a 14 inch freelength spring, and uses 2 inches of preload. There are two spring rates available: 550 lbs and 687 lbs (gas vs diesel truck). The 687# spring raises the front about 2/3rds an inch, but makes the front skip at speed.
The shock is a 7 inch travel and the tire moves about 8.6 inches (baller I know)
This truck, like most production vehicles, does not articulate very well in the front. So taking off the stock sway bar helps a bit, but it still just doesnt compress that easy without significant chassis movement. Now on the flip side, there is a little more than wanted amount of body roll when driving.
I have front bumps and when they have 80 psi there doesnt seem to be any change in body roll. Up that to 100-115 psi and the trucks body roll is perfect. I have 16mm air gap of oil in the bumps.
So the stock bar is too stiff. The 687 # spring is too stiff, running bumps over 80 psi is out because it makes the truck skip off road and when you G out it almost launches the truck back into the air.
If I fabricate some sort of "nascar" style sway bar, like a blade bar; how do I calculate the what stiffness or weight rating that I design into the new sway bar?
I assume I would be trying to chase down that 80 to 115 psi effective spring rate? That seems pretty light to me. I can get the math done and calculate the thickness of the main torsion bar and the design of the arms. But what magic number I want to be shooting for in "strength" or "spring rate" of the sway bar is the question. I definitely want to get pretty close to what I need and design an adjustable blade to fine tune it. But I'd like to start off close.
(And then I get to rip it all off and sell it next summer when the stock stuff gets replaced)