Ron Sutton Offset 3-Link install

[Ron Sutton]

Hi Bryan !

Originally Posted by carbuff

I thought I read this here in this thread, but I can't locate it at the moment... You (Ron) mentioned doing a rear axle with a 13" high upper link from the axle centerline. Looking at the side view of the axle being built here, based on these angles, that would go right through the crossmember for the rear coilovers. How do you deal with that?

Related question... If you draw a straight line between the upper and lower link mount points, it doesn't pass through the centerline of the rear axle. Why is this? Is there a specific reason that the 2 are located that way (behind the axle centerline)?

So many questions, I know... I am loving learning about these details, so thanx as always for sharing so generously!

You probably read that 13" number in a different thread. Yes, for an autocross client with a twin turbo LS on 200TW tires ... we placed the top link mount 13" above the rear axle CL. It has amazing grip.

One of THE most important design points on any link suspension is ... how long are the "levers" ... which is what the upper & lower housing brackets really are. The length of the upper & lower housing brackets determine how the rear end's rotational torque is distributed. Just to help understand what we're dealing with ... a car with 550# of torque, a 2nd gear ratio of 1.76 & rear gear ratio of 3.70 puts almost 3600# of torque attempting to rotate the housing (exiting a corner in 2nd gear).

How that torque is distributed through the upper & lower link housing brackets is called torque distribution. The upper link lifts the chassis & loads the tires ... while the lower links simply push the chassis forward. This ratio matters MORE than anti-squat, but is rarely understood.

With Ron Myer's Camaro, the lower link mounts 5.5" below the axle CL & the upper link mounts 5" above the axle CL. That ratio puts 52% of this 3600# torque through the lower links pushing the chassis forward ... puts 48% through the top link pulling up ... lifting the chassis & loading the rear tires. This will be excellent with the slicks he plans to run.

With my client's car that has the upper link 13" above axle CL ... he wanted killer, mean grip ... on 200TW tires ... for running Goodguys & USCA/Optima. So his top link is 13" above the rear axle CL. Yes ... well up into the trunk area. Ron has different tires (slicks) & different priorities. Ron wanted the most grip possible while keeping the factory trunk floor intact. My other client wanted the ultimate grip possible with 200TW tires. I help my clients achieve their individual goals by tailoring the "lift & load" ratio.

To answer your other question, the centerline of mounting points do not to run through the axle centerline. The farther back we make the top mount, the more leverage we are giving the top link to "lift & load".