With the increase in curiosity of the left rear limit chains being used in dirt modified racing we figured it would be a good opportunity to talk about what they do... well some of the main things that they do.
In simplest form, it limits the suspension’s allowable travel. But what benefit does this have for you the racer? To explain this best we need to dip into the world of physics and vehicle dynamics a little bit, but nothing crazy.
First, the only thing that stops the suspension’s travel in a standard modified is either the shock “topping out” at full extension or the rear end tube making contact with the frame run under it. Topping a shock out is not recommended and often times the distance between the rear end tube and the frame can create excessive roll.
It is important to remember that traction creates roll and roll does not create traction which leads to the second notable point. Since modifieds only turn left, when they go into the corner the right side of the car compresses and the left side extends. This creates a “Rising Rate” of force in the right side and a “Falling Rate” of force in the left side. Rising Rate in force means that the more the car rolls, the greater the potential force is to be transferred/generated to the right side. This sounds great to most, but what is often overlooked is that this force is lost from the left side during roll. This means that the further the car rolls and the left side extends - the lower the force will be on that side. If you can limit this travel though, it allows you to reduce the amount of overall force that can “leave” the left side of the car.
The third point that is equally as important to this quick post is that the limit chain is not the only answer for you to get a faster and better handling race car. We wish it were, but your overall vehicle set up and shock valving will still be the most important piece of the puzzle and when combined with a limit chain it can result in great improvements. Our Left Rear Speed Chain allows you to adjust something that traditionally is fixed amongst most all cars allowing you to fine tune your set up further than ever. We hope this helps and if you have any questions on your set up, our products, or anything stated in this post please feel free to contact us.
Dig Race Products
607-218-6282