Towing Your Vehicle Basics: Understanding Load and Sway Control
Everyone that races on an oval track and many that race on drag strips, road courses and even in the desert, have purpose built race cars that are not street legal. Getting these cars to the track is the same now as it has always been. You load ‘er up on the trailer and haul it to the track.
Think of all the money and time you spend on your purpose built race car. The last thing you want to have happen is to miss an event because of an accident or show up late because your tow vehicle’s inability to carry that weight properly. We’ve heard of cars coming off the trailers and a couple of cases where the trailer started fish-tailing till it turned over.
Thankfully, we haven’t seen it happen, but we have witnessed tow vehicles so weighted down that the headlights pointed up to the sky as if searching for incoming aircraft.
We decided to check in with Hellwig Products, specialists in load and sway control, about safety benefits and better towing performance by controlling the load and sway with your tow vehicle.
Our primary goal with load control and sway control products for tow vehicles is to help racers get to the track, and then help make sure they can return home safely. – David Wheeler
Hellwig Products suspension engineer, David Wheeler, explained the issues relating to towing by saying, “it’s true. If you hook up your trailer and the headlights point up in the air, the front end of your tow vehicle is very light and the alignment is off. This throws everything out of whack. Your caster, camber and toe adjustments are off so much that you can’t be sure what the vehicle is going to do.”
According to Wheeler, “the biggest thing you need to worry about is getting the load level. The tow vehicle will improve it’s ride comfort and more importantly, the vehicle will be predictable and stable. It’s a safety issue. Our primary goal with load control and sway control products for tow vehicles is to help racers get to the track, where they can have some fun, and then help make sure they can return home safely.”
Using Your Family SUV as a Tow Vehicle
Many grassroots racers have attempted to use their family daily driver as a tow vehicle on Saturday nights, only to discover that the factory suspension was not built for handling a three-thousand pound car on a thousand pound trailer. It’s not uncommon to see a racer attempt to use the family’s Tahoe or Avalanche as a tow vehicle.
Most of the time, the rear suspensions on these type SUVs are compressed to the point where the chassis is riding on the bump stop. While it may seem obvious, Wheeler repeated the basic rule in towing, “The tow vehicle’s suspension must be strong enough to support the trailer’s weight. When the trailer’s tongue weight lowers the rear end of the tow vehicle and lifts the front end, you’re gonna have problems. The vehicle will not handle well and many of the suspension and steering components will wear out at a quicker rate.”
We asked Wheeler about using the family SUV to haul a racecar to the track. “That’s a tough proposition for a factory chassis with rear coil springs. You don’t have many choices, but we engineered a Power Lift kit specifically for this situation. When you’re options are limited to buying a new tow vehicle or stop hauling to the track, our Power Lift air spring kit costs less than the registration and license on a new tow vehicle, and it gets the job done.”
Upgrading to an air suspension that is adjustable for loaded and unloaded conditions while providing stability, control and the ability to level the load automatically, spreading the tongue weight across the vehicle’s axles, seems like a very smart investment to us. You can find out more about Hellwig Products Power Lift kit for truck and SUV chassis with coil springs by clicking here.
Weekly Saturday night racers tend to operate more with a limited budget than any other type of racing. Knowing this, we asked Wheeler where a tight budget racer could make a difference in his tow rig. “A sway bar change will make a big difference in the way your tow vehicle handles and greatly improve the safety aspect. At a bare minimum, changing the vehicle’s sway bar is recommended,” he stated.
There are a lot of positive rationale for upgrading the sway bar on any vehicle that will be carrying a load or towing. “Changing the sway bar is a very easy task and once it’s installed, there’s virtually no maintenance. You set it and forget it, but the improvement in ride comfort and control is greatly enhanced,” said Wheeler adding, “even if you are installing an air bag kit, a sway bar is a great compliment to the system.”
Wheeler also pointed out that Hellwig Products offer a complete line of sway bars for lifted trucks. “There’s nothing to modify. They are a bolt on component that is designed to work with trucks that have been lifted and still offer the same quality sway control and ride confidence.”
It’s important to remember that sway control and load control work together. If you’ve added a sway bar upgrade to your tow vehicle, check how the load is affecting your suspension. Even on a budget you can level the load with helper springs. Wheeler dismissed any question of helper spring effectiveness by saying, “adding a helper spring can dramatically assist controlling the load because they tend to be mounted more outboard than other types of load control. By design, these helper springs spread the load out to the axles evenly and have the advantage of adjustability.”
How a Sway Bar Is Hot Formed
Sway Bars. “I Love This Bar!”
If there was ever an appropriate segue with intro music, Toby Keith’s “I love this bar,” is the perfect chorus for a sway bar segment. When Wheeler explained that the minimum upgrade every racer should consider was upgrading their tow vehicle’s sway bar, we felt that it was important to understand the function of this component and what to look for in an upgrade.
“Essentially, a sway bar is a torsion bar,” explains Wheeler. “It doesn’t come into play until a vehicle tries to take a corner.” Take some time to think about how many corners, bends in the road, lane changes or even gusts of wind against the trailer take place from the start of your haul till you get to the track. “When the body tries to roll, the sway bar pushes back against the body which keeps the body flatter and improves the handling performance,” added Wheeler.
Melanie Hellwig White, Marketing Director at Hellwig Products is extremely proud of the Hellwig sway bars, and she has a right to be. As the fourth generation Hellwig family member to become involved in the family owned business, Melanie grew up learning all there is to know about sway control. “Our sway bars are heat treated, 4140 chromoly steel which is 50% stronger in fatigue strength than non-heat treated sway bars,” she proudly states.
Both Wheeler and White reminded us that Hellwig’s sway bars are 100% American made in their ISO9001 Certified facility in Visalia, California. “We offer solid, tubular, and heat treated sway bars to match any suspension requirement,” said White. Wheeler added, “depending on what your requirements are for the vehicle… what you want to get out of it, we can match up a sway bar to help you get there.”
The bottom line on sway bars is performance. The right sway bar on your tow vehicle will improve the drivability and traction, help with better cornering and less body roll. When you have your pride and joy racecar and trailer in tow behind you, better performance from your tow vehicle can be the difference in getting to the track or not.
Scratching the Surface
Hellwig Products has been developing Load and sway control products for everything from golf carts to Class 8 trucks, like Kenworth and Peterbuilt tractor-trailers, and they’ve got over sixty years of experience and research behind them. We’ve barely begun to scratch the surface on understanding the dynamics behind setting the suspension on your tow vehicle but one thing is abundantly clear in the basics: all the horsepower in the world isn’t going to make towing your race car more stable or safer. Getting the available power to the ground equally, with all corners of the tow vehicle working together, will make a dramatic difference in getting to your next race.
We started by saying “think about all the money in time that you have invested in your race car,” and we are going to end by punctuating that point. Is that new cold air intake going to help your tow vehicle get your race car to the track or will that new sway bar? In our book, our race cars are not worth the risk. A safer and more stable haul wins out over the handful of potential horsepower.