Every drag racer, from your weekend bracket racer to a professional heads-up team, knows that adjustable suspension components allow you to zero in on the perfect setup. The most common form of drag racing suspension, the 4-link, relies on a set of brackets with a multitude of staggered holes along their length to dial in the suspension. This setup is the most widely accepted form of aftermarket suspension and is commonplace in most tube chassis cars.
While the traditional 4-link has served racers well for decades and is likely to remain the standard for decades to come, if you could pinpoint one issue with this design is that, even if the suspension requires a minimal change of bar angle, simply relocating the control arm alters the ride height of the vehicle. Making these changes during rounds can drastically impact the valuable time that could be spent elsewhere. The Tim McAmis adjustable 4-Link bracket is the remedy to this, as it allows a quick change of instant center without affecting pinion angle, pre-load, or even wheelbase.
This bracket simplifies the on-the-fly adjustment, allowing one to dial everything in to extremely tight tolerances of 1/8-inch increments. It also surpasses other 4-link brackets in allowing for an infinite range of chassis geometry, while opening the door for the chassis tuner to take a scientific approach with a wider range of instant center options.
In comparison to your standard 4-link plates and brackets, the adjustable version is a more robust design, employing a heat treated 4130 billet main arm for maximum strength. Check out the video above to get a more in-depth look this remarkable design and see Tim McAmis for even more race car ingenuity goodness.