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Message: [QUOTE="Jacob 76, post: 1075739, member: 6789"] There is a ton of math and science behind the actual design of suspensions but I will just cover the basic idea of a STREET suspension. I like radius arms for street trucks because they are stone age simple and very easy to tune. That is why ford used them for many years on 1/2 tons and in '05 started putting them onto their bigger pickups and also dodge started doing it on their bigger pickups too. They are the perfect compromise of everything a pickup needs to do. In design, make everything that travels in pairs, travel parallel with each other. Meaning make your drag link and trac bar parallel and of equal length when viewed from the front AND top (this is the part 95% of people don't do) so when the radius arms cycle they will not bind and create bump steer. Make your radius arms parallel when viewed from the top so when the trac bar cycles it wont create roll steer. The reason for this is because if they are narrower at the frame like many people design them, like the early broncos and 67-79 F-150s, as the trac bar cycles UP the left side arm gets "longer" in relation to the wheelbase of the vehicle while the right side gets "shorter" and this will ALWAYS create roll steer to the right. The opposite happens upon droop. The length and slope of the arms will create dive or anti dive. I wont get into the math of it but basically it will change if your front end dives upon braking or (if your arms or links are short and steep like on dodges with huge lifts) the body and chassis will try and pass the front axle and create a very uneasy feeling while braking. I like joints, like EMF or Ballistic joints, not bushings, because they are more "fluid" in their movement but they do create more road feel and vibration, this is just personal preference. The stiff ride is 100% dependent on spring and shock choice/tuning if you design your suspension based on those principles. That is the great thing about coilovers though is that trial and error is very easy. I'm sure someone will come here and argue about the radius arms being parallel, but the short answer is that they are wrong. Much of this goes out the window for off-road suspensions but I wont get into that right now. [/QUOTE]