The Set-Up with Steve Humble: A glance into the engineering behind hillclimb racing.

Steve Humble is making a setup adjustment on the March 79A at Speed Classic Cape Town.
PHOTO COPYRIGHT: Slipstream SA

When you think motorsport, your first thoughts usually revolve around – the cars, the speed, the circuits, and the wheel-to-wheel action that it brings, but if you delve behind the detail, then do you discover the little intricacies that makes motorsport truly unique, areas such as: aerodynamics, gear ratios, etc. and last but certainly not least, the set-up. 

Perfecting each of these areas will help separate a quick car from a controllable one, and a fast driver from a confident one. 

Across motorsport’s many disciplines, excelling and setting yourself apart requires both speed and confidence in the car that you are driving. That makes set-up crucial — whether you’re fighting at the front for victories or bringing up the rear. 

If you look across the spectrum of motorsport, there is a vast array of disciplines. You have single-seater categories, such as Formula 1 and Formula E, which sit alongside endurance racing with GTPs, Hypercars, and GT3s, as well as off-road disciplines like Rallycross, rallying, and Rally-Raid. There’s also motorcycle racing — MotoGP, the Isle of Man TT — and, of course, hillclimb racing. A single-seater set-up cannot simply be transplanted into rallying or any other discipline. Each car requires a unique set-up approach to extract the most performance, which means set-up work is specific to every championship and series.

To provide you, our reader, a clearer understanding of ‘the set-up’, Slipstream SA will explore its intricacies across a range of championships — from hillclimbs to rallycross — starting with hillclimb racing.

Charles Arton is heading to the start line in his March 79A.
PHOTO COPYRIGHT: Slipstream SA

Hillclimb racing is all about pushing a car to its limits along a course with unpredictable bumps, camber changes, and blind crests, which means every metre matters. That in turn means tuning a car for tight, technical sections while also accounting for aerodynamic performance and immediate tyre grip is essential.

Slipstream SA caught up with Steve Humble at Speed Classic Cape Town to gain insight into what it takes to set up a race car for hillclimb competition. There’s no better perspective than that of a seasoned mechanic and team principal, and Humble fits that bill.

Humble is the lead mechanic for Charles Arton, who drives a classic Formula Atlantic March 79A single-seater. 

“This is a March 79A, a former Formula Atlantic car, originally with a 1,600 BDA, now running a 2-litre BDG (engine). It’s actually an aero car, though we don’t run the full aero sidepods,” he explained.

The March 79A was developed in the late 1970s — an era defined by ground-effect experimentation, loud engines, and chassis built through a blend of hands-on development, racing knowledge, and early wind tunnel principles.

The sidepods on Charles Arton's March 79A, with the visible ground-effect skirt.
PHOTO COPYRIGHT: Slipstream SA

In the period, the March 79A was designed for smooth, high-grip circuits with long straights and fast sweeping corners. But hillclimb racing is nothing like circuit racing. As Humble points out, "car setup is extremely difficult to define because everywhere is different. Hill climbing is different from a main circuit. The main circuit tends to be a lot smoother. Hill climb is always a compromise because there is zero time to warm anything up. So, what we are trying to achieve is instant heat and grip from the tyres. And the way we do that is by running softer setups and hopefully making the aero work as early as possible."

Humble explains that “car setup is extremely difficult to define because everywhere is different. Hill climbing is always a compromise because there is zero time to warm anything up. What we’re trying to achieve is instant heat and grip from the tyres. The way we do that is by running softer setups and hopefully making the aero work as early as possible.”

Where circuit racing often relies on downforce and tailored setups that suit the driver's needs, like more understeer or oversteer, a hillclimb car needs to generate confidence and grip from the very first corner. Every adjustment — from springs, dampers, camber, tyre pressures, wing angles — is aimed at responsiveness, agility, and generating driver confidence.

When asked what matters more — horsepower or setup — Humble’s answer was straightforward. “Raw horsepower means nothing if you can’t control it and keep it on the track,” he says. “You can have 1,000 horsepower or 100 horsepower; if you can’t control it, it’s basically useless.”

A good setup is about finding the perfect balance to give the driver good confidence, which will enable him or her to extract the maximum lap time achievable, but in order to get there, you may need to make a few compromises. 

“It’s a compromise all the time,” Humble says. “You have to take into account springs, anti-roll bars, caster, camber, differential settings, aero, and whether the car actually responds to any of those changes. If it doesn’t, then you’re just battling a flexible car.”

A flexible car is something no driver wants, but at times, they have to deal with it. Forcing a driver to underdrive due to a lack of feeling, which results in a lack of confidence, making it harder to push to the desired limit.

Charles Arton smiles ahead of his final run up the mountain.
PHOTO COPYRIGHT: Slipstream SA

Ultimately, a great set-up is built around the driver. “You should always set a car up for a driver, so when the driver comes back, he turns around and says to you, the car is better than he is. That way, you know you are actually in the ballpark, because when a driver comes back and says the car is trying to kill him, then you are not in the ballpark,” Humble explains.

Driver feedback becomes the lifeblood of performance. Without it, set-up work devolves into educated guesswork. “A large portion of it isn’t just guesswork, it’s experience,” he says. “I’ve been doing single-seaters for 30-odd years. A lot of it crosses over, and then it’s a matter of fine-tuning.”

To the layman, a set-up might simply mean tweaking a car to make it faster, but in reality, it is far more complex. As Humble explains: “There's the aero, and you've got to make sure that your weight distribution is correct front to rear, not just side to side. So, the corner weight of the car, I guess, is very important. You also have to make sure that you've got the right amount of weight front to rear. You can't corner weight balance the front axle, but still have too much weight on the rear. Otherwise, no matter how good the car is, if you don't have enough weight on each axle, then you're not going to get any grip out of it.”

A detail many overlook, yet Humble reminds just how razor-thin the margins can be: “Half a kilo can make a difference with a single-seater.”

For most teams, a baseline set-up acts as a compass — a known, stable configuration that provides a direction to begin with. “You can only get a track-specific setup with a driver that can actually give you the information. So, experience will give you a baseline setup that works on most single-seaters. I've got a baseline setup that I know works on most single-seaters, but then it's down to the driver to tell me what the car's doing. So, we can then fine-tune or move forward from that point, or backwards, as the case may be,” he explained.

At a hillclimb, those fine adjustments begin even before the engine fires. “We need to know whether it’s got the right gear ratios, whether you're having to gear up or gear down for a corner, or whether you can hold it through the corner and in the right rev range,” he says. “Because if you're changing down mid-corner, or you're having to change up mid-corner, you're not right with your gear ratios, which means that the chassis is then having to do things or cope with things that it shouldn't have to do.”

Unlike modern single-seaters, the March 79A does not have a data logger or an ECU to gather data, which means everything is analogue – and everything is based on feel. “This car’s from the 1970s,” Humble says. “There’s no computer data coming out of it for me.” That places the responsibility squarely on driver feedback and mechanical understanding — the kind of engineering that existed long before laptops entered the pitlane.

Charles Arton on route to the start line at Speed Classic Cape Town.
PHOTO COPYRIGHT: Slipstream SA

With a clear understanding of just how crucial the set-up of a racing car is for hillclimb racing, we asked Steve Humble what fans most often misunderstand about a car set-up, to which he explains: “Tyre pressures and tyre temperatures. People don’t understand the need for accuracy. They use cheap gauges and assume they’re correct.”

It’s a worthy reminder that setup work isn’t always about big budgets or sophisticated technology — sometimes it’s about the experience and knowledge that you’ve gathered over a decade to help the driver find a direction that will make him or her comfortable with the car.

Humble offers one final piece of advice to aspiring drivers, in relation to set-up work, and said: “Find yourself a good team with an engineer that actually does know what he's talking about.”

With a clearer understanding of the intricacies behind setting up a car for hillclimb racing, attention now turns to the next installment, where Slipstream SA aims to explore many other motorsport disciplines – from off-road to circuit racing – as we reveal how the pursuit of a perfect lap, or race, begins long before the car hits the track.