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Move vertically. For panhard suspensions, the roll slope goes from the panhard to where the lower links would meet. Right now that lower link point is above the panhard point.
That's a good point about the radius arms. I am not really sure what that load look like. It may be worth looking at the link sizing tab to see what sort of link you may need.
Thanks for the clarification
No. But it wouldn't be too hard to jerry rig it to give a relatively close output.
That wheelbase and the lowers being tucked into the frame a bit, the belly height is probably going to be a problem. Rear anti's may be a bit high. For road and highway miles, having understeer tendency for the roll slopes is recommended. Same applies to the front for anti's and roll slopes.
Ok, thanks, so should I shoot for just under the 50% mark for the rear anti’s? I think I see what you are saying about the belly height. I can raise the belly up a couple inches for clearance but I was also a little worried about that raising my CoG and the vertical angle that my lower control arms attach the axle to the frame. I guess that’s all in the balancing act.
Under 50% at ride is a good target. Long wheelbase crawlers are tricky. There is a push for longer links, which has its own issues and benefits. CG tends to be higher. A high CG isn't punished on steep climbs, but side hilling is. There are some options to keep the CG low, like not making the belly flat from front to rear.
The anti squat is on the high side for what you are planning to do with the rig. I would like to provide more input, but the earlier versions of the calc are a bit limited in the information they provide.Looking for input on this set up. Toying with mounting uppers outside the frame and lowers closer to the Centerline (axle). Will be a custom frame. Anything look seriously wrong with these numbers? Is it silly to have lowers like this?
Idea is good for rock crawling (45%), a little bit of go fast dessert fun (35%), and moderately comfortable on the streets (20%). Rocks are priority, but only just.
Antis are the only thing in the calculator that change with the drive and brakes biases. The anti values are scaled by the biases.
Thanks for the feedback. I realize the calc i'm using is older. I'm just working on back half geometry at the moment. So what's the rule of thumb for upper and lower control arm lengths? I think I read somewhere you want the upper to be about 75% the lengthof the lower. So if I had a 40" lower then I'd look for around 30" uppers.
75% is a good starting point. I don't think I have looked at the relative lengths beyond asking "I wonder what it ended up at."
Pinion angle is good. You want a negative value (pinion down) as suspension goes up. Otherwise, nothing seems way. Raising your upper frame mounts a 1/4"-1/2" will get the antisquat down slightly more. Ideally the entire curve stays below 50%
It all seems fairly normal for a crawler. The importance of flat lowers is less at lower speeds. If you want to fine tune, I usually recommend keeping the entire anti curve below the bias to that end of the vehicle. I would hazard a guess your CG will end up slightly higher and should take care of that.
Your uppers are more than 3 feet apart.
Yeah but it’s under sprung, it was with leafs on it as well. Just feel like the front body rolls more than it used to. Rear with the bar feels fine
That is an extremely complex answer. . The short version is its a mix of geometric, forces, and roll and pitch coupling.
Something isn't adding up here. The rear should roll the same angle as the front give steady speed. Is it doing this when accelerating or braking?
I dont, I can run over to the local cat scale this week to get f/r weights.
