Make it handle

[robnolimit]

IAN30, good questions. First rule, "every action creates an equal and oposite reaction", so as the axle is trying to rotate the tire forward (lets say clockwise), the axle housing wants to rotate the oposite direction (counter-clockwise). The 25% rule is so that you have enough leverage to control the axle rotation, its a good rule of thumb. one more note, we want the truck to go "forward" under acceleration, so to get the leverage to help, put 2/3 of your bar span below the axle CL, and 1/3 above. * top bars that are right on the axle CL (elevation) WILL NOT transfer any wieght. ** 4-bars that are parallel (top to bottom bar) WILL NOT transfer any wieght. When it comes to three links (wishbone style) and triangulated four bars, BE CAREFULL, these set-ups build with urathane bushings all around start to bind any time they move away from ride hieght. you can help this by runnung rod-ends in the upper bars to allow them to articulate. Our kits are desinged to have the lower bar level to the ground and the upper bar slopping down at 4-5deg. at RH.

On another note, we now have custom tank-crossmember kits to fir 67-87's with Porterbuilt and others step notch kits. I'l post up some picts on the 67-72 section.

[Ian30]

Rob, I appreciate you giving out all this advice, I've had a hard time finding the information that you've given here so freely. It's interesting how much of the information out there is just people spreading hear say and not actual practical stuff. I just want to start off with a decent handling suspension without any major quirks that I can possibly tweak in the future if I want more. Can I just recap what you have suggested regarding rear suspension setups and ask a few more questions just for clarification.

Low long Panhard bar - ideally equal to axle centerline.
A light swaybar - Do I run without at first and add it if needed later on?
Mount the links wide
2/3 of link verticle separation below axle centerline
Lower link approx. level at ride height, top link sloping down 4-5 degrees
Instant center should be in front of the front axle
anti-squat less than 100%Would it be better with a number below 50%??? How low is too low??

OK, thats all I can think of for now. I am also attaching some free excel link calculators that I found. I am using the 3 link for this setup even though it will have 2 upper links as the four link calc is more for triangulated setups. I don't think that changes any of the numbers having two upper links. I don't know if you have seen these before, but can you please look at them and give me your opinion if you think they are crap or a good starting point.

Thanks again, Ian

[Ian30]

ok, I have thought of another question. I have a bunch of pivot joints from another project. Would it be better to use these at the axle end or would it be best to use all polyurethane bushings everywhere? assuming no cost involved.