This 4-Link suspension is the best Pro-street suspension available anywhere. It is designed to be high tech throughout. One piece stainless steel urethane adjusters are used in the links with left and right hand threaded tubes so you can preload the suspension in a hurry. For a track locator, we use the best. Our (Wishbone type) works independently of the 4-link, unlike the diagonal design. It features urethane bushed pivot points and is adjustable. The re-alignment tube features a snap-in space-age plastic bushing, (developed by Auto Weld), for a grease-free mechanism. The coilovers are urethane bushed and feature external adjustable shock valving, (no taking the spring off and collapsing the shock to set the desired settings): Simply twist the button at the top or bottom of the shock to adjust valving. Also available is a torsion bar type (anti-roll bar), 21" wide, designed to help with leaning associated with very narrow 4-link cars and race cars. This allows the use of lighter spring rates but still helps in cornering. Ultimate II comes completely jig-welded. You get a jig-welded main frame with all mounts and brackets, drive shaft loop, coilover shocks, 4-link, pro style 9" Ford housing with brace, Wishbone track locator, all jig-welded and complete with hardware. Parts are available separately. Also available are resplined or race axles.
HOW IT WORKS:
Street geometry and race geometry are built in. This is not a race 4-link with urethane bushings only. It is a 4-link designed expressly for pro-street use. For street usage, both upper and lower links are parallel with each other, and are also parallel to the ground. This is the only way a 4-link should be used on the street. The advantage of this is that you will have a softer riding, better handling vehicle by allowing the suspension to move the way a stock suspension is supposed to move.
Figure #2 shows the advantages of an Auto Weld Pro-street 4-link. It is able to handle uneven road surfaces or bumps without sending the jolt up through the whole car as in figure #1. Also, it is worth mentioning that when the links are run parallel with each other and with the ground, you effectively eliminate the roll steer problem encountered when links are in a triangulated mode or aren't running parallel to the ground. "Roll Steer" is the tendency for the rear axle to steer the back of the car. This can occur when a car leans going around a corner or when it goes over a bump. This is due to the arcs and geometry of the rear suspension, not a desirable situation for street driving. So, for everyday driving, it is best to keep links parallel.
For drag racing you want to bring the instant center back toward the rear of the car. One way to do this is to lower the top link in the front bracket. The instant center is nothing more than the intersecting point of the links. If you were to draw an imaginary line through the links, the point at which they would intersect is the instant center, the focal point of the rear suspension. In a ladder bar car situation, you are stuck with the instant center whether it be a 32" or 36" ladder bar. The front rod end hole is the instant center. About all you can do is to either raise it slightly or lower it. The ability to tune is greatly hindered. With OUR 4-links the tuning is infinitely greater. You can move the instant center forward, back, up, or down. The location of the instant center (or focal point), of a suspension determines how hard the suspension is going to hit the rear tires when you launch your vehicle. The further back or up, the harder the suspension will strike the tires.The further forward or down the instant center is, the less hard it will strike the tires respectively. Some experimentation will determine the best angles and locations of links for your particular situation. In a pro-stock, the instant center is somewhere around 48"-52" from the center of the axle and about 0"-2" off the ground as opposed to the super stock type car, which has its instant center 32"-40" from the axle and 6"-10" off the ground. These are, of course, two extremes.
There are many variables in a racing suspension ... power of motor, weight of car, clutch versus automatic, shock valving, spring rates, front suspension type,and many others. It is not our purpose to confuse the user but just mention that there are many variables in every car and truck whether it is pro-street or race. This is why the ULTIMATE II came into being. It is the finest pro-street 4-link suspension you can put in your vehicle, whether it be a late model car, street rod, or pick-up. If you are building a pro-street, put the best under it........ULTIMATE II !!!!!!!