Quote:
Originally Posted by robnolimit
Auto-X (OK, Fast Auto-X) is probably the hardest challenge for your suspension/tires than anything else (ON-road competition) we see higher shock and spring rate changes than anything else. Honestly, many Auto-X'ers have surpassed the G force loads of a lot of road racers, it's just that on an Auto-X coarse, the 'time' of the G event is much shorter. The 'violence' of the tire loading is much harsher. So, allowing the body to roll a bit more (still with the rate controlled by the shock) slows down the rate of tire loading and allows the tire to get a grip for a bit longer.
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Whoa whoa whoa, ok but in your 'make it handle' thread you said
"There are a lot of concepts out there about handling. Here is one thing i see a lot at Auto-x and track events. The problem is that the car (truck) is loose through the corner. The solution is to disconnect the rear sway bar. ?what? I see this all the time. OK, I get it the first time, but this is backwards."
"Having a low roll center will produce a good 'bite' in and out of a corner, but it produces more body roll. So, a combo of a low panhard rod and a light sway bar will give you great results."
"Try to keep the swaybars close in size. 1 1/4" front with 1 1/8" rear is good for more streetable trucks, 1 1/2" front with 1 1/4" rear for more aggressive handling."
"Swaybars. GO BIG, but keep the back within 1/4" of the front."
"Lets get back to the main topic, HANDLING. One of the best upgrades you can do is swaybars. Swaybars, or Anti-roll bars, work by adding traction (downforce) to the outside tire. To do this, the swaybar has to take downforce away from the inside tire. So if you think about it, you can go 'too big' on the bars. If you went so stiff that the inside tire lifts off the ground, then that tire isn't helping at all. The balance between the front and rear bars is called "roll couple", and here's where a truck layout changes normal thought. In a normal performance car, with say 52% front weight and a low CG, the roll couple needs to be up around 80% (calc for this is really complex, so think of this as a comparison number), but in a truck, with 58% front weight and a higher CG, you aqctually need to move the roll couple BACK, maybe to 65%. This means that in comparison to a Camaro that would run a 1 1/4" front and a 7/8" rear, the truck would tend to 'need' a more evenly matched bar set. Say 1 1/4" front and 1 1/8" rear. Most retailers/manufacturers are missing this and selling bar sets in 'car' sizing, so be carefull. "
"Last weekend in Pleasonton, I was explaining this to a few people and most believed that a smaller rear bar would help the truck turn, do to the added cross weight from the inside rear to the outside front - as the truck leans over. So, I pulled one of the rear swaybar links on our 55, effectively it had no rear bar. The truck pushed like crazy, and on the second lap, I spun out trying to throttle steer it through a corner. Bad outcome, but it was a good demonstration of swaybar tuning."
So look, clearly I've been paying attention to what you're saying but I've seen you contradict yourself several times -- this isn't the first. I treated the "make it handle" thread as an introduction to performance handling and I feel like I learned a lot and I appreciate the time you spend to put that knowledge out there.