MSD.LIVE DRIVE: Making the Drivetrain Switch

11th May 2017


Going from front-wheel drive (FWD) to rear-wheel drive (RWD) can be a steep learning curve as Turn Eight racing drivers Pip Hammond and Gavin Johnson found out when moving from classic stock hatch to the Porsche championship.

Having both raced in 750 Motor Club’s Classic Stock Hatch Championship, Hammond and Johnson made the decision to switch to a 1979 Porsche 924 knowing that a RWD car was going to be very different from the FWD classic hatches they’d raced in the past.

Johnson is relatively new to racing having raced karts, picking up three podiums in his first three races, and winning the Novice Gold Cup at Three Sisters in Wigan, before joining Classic Stock Hatch. Hammond is a two-time Classic Stock Hatch champion and has a little bit of experience with RWD, having raced a Triumph TR6 alongside his FWD Citroen Saxo and Vauxhall Nova.

Preparation was important ahead of testing the Porsche, but there was only so much they could do without getting in the car.

Hammond says: “I watched a lot of YouTube videos and Gavin got me into iRacing. You can’t get a full simulation without a decent rig but it helped me with some of the Technical principles. I’ve also run a couple of one-off races in RWD cars before, but I never really had the time to learn them, so iRacing probably counted for better preparation!”

Testing at Donington in the wet was a good chance for them to learn the car and see how it handled when it wanted to slide or spin. While an FWD car can be easy to correct after a moment on track, they had to be a bit more gentle with the Porsche. Johnson says: “In an FWD car you should bury the throttle and turn to keepthe wheels facing where you want them, trust the car and then react by straightening out as it snaps back! In a RWD car you need to be less aggressive with the steering and much calmer on the throttle. Don’t panic and don’t brake.”

Hammond echoes this: “I think the feeling of losing it in the first place is the same but the similarities stop there. I actually spun the Porsche in the rain on my very first lap in the car, and from that point I had a good idea of the limit. The key with RWD is to do the opposite of what got you in trouble in the first place, without reacting in extremes. Whipping it to the opposite lockstop will just get you in trouble – just mirror the actions that got you in trouble and don’t ask more than the tyres can give.”

A RWD car also grips differently when going round a corner – which means finding that limit and learning to manage oversteer is really important. Johnson says: “The most obvious difference to a relative newcomer like me is that when on the limit, my FWD cars were keen to understeer and push on, whereas the Porsche tends to oversteer. I’m still adjusting and learning the feel, but I find the oversteer easier to manage now.”

While the differences are still noticeable, the Porsche is a good stepping-stone for anyone looking to drive more powerful RWD cars having come from an FWD background. Hammond says: “The Porsche runs on a Toyo R888R control tyre that affords a lot of grip – so it’s not as big a learning curve as it could have been. The 924 has relatively low power and high grip using those tyres. You can push it very hard before it starts to slide, so you can actually turn in more aggressively than in a more conventionally gripped RWD car.

 

“With the power the way it is, you can slide the car into the corners to scrub speed and start rotation, but if that slide carries on into the mid-corner and beyond then you’re losing out and you can’t rely on the throttle so much to help you out!”

Johnson has taken sharing the Porsche as a chance to learn from Hammond, a two-time championship winner. He says: “Working with Pip has made the switch to RWD much smoother for me. Pip’s input to my testing and his ability to articulate technical information and analyse data has proven to be invaluable. He’s fast in everything from lap one and gets the most from even the briefest test session – a key skill when club racing on a budget. I’ve gained time and confidence every time I’ve had him in the car with me.”

Testing together while using Harry’s lap timer means they’ve been able to see exactly where time is being lost. After a disappointing weekend at Rockingham for Johnson then a much more positive test session at Oulton Park, Hammond went through all the data only to find that Johnson was losing time on left-hand corners – something a lot of drivers struggle with – often finding the right-hand turns more natural.

This has allowed the pair to work on their weak areas and continue to improve. While Hammond maintains his 100% win record after an almost-perfect weekend at Snetterton at the start of the season, the rest of the field is getting quicker too.

Both drivers agree it’s easier to go from FWD to RWD. Hammond says: “There are aspects of being quick in a front-wheel drive which are actually a little counter-intuitive to those who’ve raced karts or a RWD.

“I think FWD specialists are often seen as having a bull-in-a-china-shop approach but there’s a real knack to getting it just right. In my experience, it’s almost a case of arrive too fast, turn in hard and too late, then hit the gas pedal. RWD is more of a natural driving style.”

If you’re a driver looking to make the switch, Johnson has this advice: “Try testing a RWD car and take an experienced driver with you. There are plenty of differences but the balance of a RWD car like the 924 will surprise you. It’s exhilarating when you master those sweeping bends.”

Driving a RWD car can be a great way to develop as a racing driver, as Hammond explains: “If you start with something that has a similar power-to-weight ratio as cars you’ve driven previously, you’ll have less to get used to. You’re probably going to need to smooth your driving style a little, but it will make you a better and more versatile driver in the long run. Just don’t ditch FWD completely – keep your eye in with both if you can.”

Switching shouldn’t be daunting and, while you’ll have to adapt your driving style, once the familiarity is there, the experience can make you a stronger driver all round. Keep an eye out for Hammond, Johnson and the Turn Eight Porsche in the BRSCC Porsche Championship.