FWD cars and racing

[Skygrasper550]

Strictly talking about performance in racing and motorsport, is there in any aspect at all where a car with a FWD drivetrain is superior to a RWD or a 4WD drivetrain? What are the real benefits, performance-wise (exclude tire wear and other factors), in using a FWD car for racing?

 

[Vegard]

Lower drive train losses for one.

 

[Bo]

Stability when you lose the car. There's a good reason RWD touring cars aren't favoured against FWD touring cars in a race situation, because once you get hit in a RWD, you're around and out. With a FWD car, you can keep the throttle buried. They're also much easier to push to the limit, since it's easier to deal with running wide a bit rather than binning the car after a snap oversteer episode.

 

[Skygrasper550]

They're also much easier to push to the limit, since it's easier to deal with running wide a bit rather than binning the car after a snap oversteer episode.

That's actually a good point. I read once that a bit of understeer is always preferred over any amount of oversteer when it comes to racing, and I agree with them. It's safer and more predictable.

 

[Bopop4]

That's actually a good point. I read once that a bit of understeer is always preferred over any amount of oversteer when it comes to racing, and I agree with them. It's safer and more predictable.

They had it backwards, oversteer is preferred.

You can't really do anything about understeer, but you can control oversteer and adjust your driving to suit a loose car, with understeer you're pretty much stuck with it.

 

[Bo]

They had it backwards, oversteer is preferred.

You can't really do anything about understeer, but you can control oversteer and adjust your driving to suit a loose car, with understeer you're pretty much stuck with it.

Both have it wrong, it's completely setup based and driver preference. A lot of drivers take an understeer setup.

 

[Bopop4]

Both have it wrong, it's completely setup based and driver preference. A lot of drivers take an understeer setup.

I've never raced a fast person who liked understeer to oversteer. Slower drivers may like understeer because it gives them confidence, but at a high level a driver wants full control. Just look at pole position laps from any series, the car is on the edge of control for maximum speed.

 

[Bo]

I've never raced a fast person who liked understeer to oversteer. Slower drivers may like understeer because it gives them confidence, but at a high level a driver wants full control. Just look at pole position laps from any series, the car is on the edge of control for maximum speed.

Button has always set his cars up for understeer. There was a feature on setup preferences on Mobil 1 The Grid many years back; it was about a 50/50 split between drivers.

 

[TheCracker]

A FWD car will likely be much better in slippery conditions.

 

[Bo]

A FWD car will likely be much better in slippery conditions.

Is that from experience when the Imps and Minis come sliding past and you're stuck trying to keep it off the grass?

 

[TheCracker]

Mid-engined Imps don't fair much better

But yeah, Mini's rule in the wet. The gap would be lesser if everyone ran rain tyres.

 

[GT'S BiG FaN]

Stability when you lose the car. There's a good reason RWD touring cars aren't favoured against FWD touring cars in a race situation, because once you get hit in a RWD, you're around and out. With a FWD car, you can keep the throttle buried. They're also much easier to push to the limit, since it's easier to deal with running wide a bit rather than binning the car after a snap oversteer episode.

Case in point.

 

[Joey D]

From a rallycross (and I'm talking about the SCCA America version) perspective, FWD does really well since they tend to do better in the dirt than RWD cars. AWD is going to be the best, but the FWD cars really hold their own and often place in the top 3 overall. I'm sure if class restrictions weren't an issue and the people I race with had more money to throw around, I'm guessing there would be some FWD cars that would easily beat AWD.

I think it really all comes down to how your suspension and diff are setup along with the tires you choose. With the right combination I think you could probably make any drivetrain superior to any other drivetrain for a given racing discipline.

 

[Bo]

S1600 cars compete against SuperNats in British RX sometimes, and are sometimes faster, so it's the stability and limits advantages again.

 

[Skygrasper550]

Case in point.

HOLY 🤬. WOW. That is a properly epic save, and only possibly with a FWD car.


That aside, the only real advantage I can see that FWD cars have over RWD cars is overall stability, because FWD cars are prone to understeer, and thus they're not keen on having their rear ends hanging out in corners. And this is especially prevalent in races with slippery conditions or off-road courses.

 

[Joey D]

That aside, the only real advantage I can see that FWD cars have over RWD cars is overall stability, because FWD cars are prone to understeer, and thus they're not keen on having their rear ends hanging out in corners. And this is especially prevalent in races with slippery conditions or off-road courses.

I can get my Neon fully sideways without the use of a handbrake and I've even spun it in a few corners due to oversteer. It really comes down to how the car is setup. I have a super beefy rear sway bar with stiff springs and struts which promotes oversteer.

 

[Crash]

because FWD cars are prone to understeer, and thus they're not keen on having their rear ends hanging out in corners.

With the right setup, you can make a car do some really unexpected things.

 

[Zenith]

They're simple to save. In oversteer you just point the wheel in the direction you want to go and floor it.

That said they're pretty poor on road courses. You don't want understeer because you'll be simultaneously be losing cornering G and acceleration. Understeer on corner exit works alright in RWD cars because it can help put maximum power down.

Outside of a handful of situations, FWD is an inferior drivetrain for performance applications.

 

[Bo]

HOLY 🤬. WOW. That is a properly epic save, and only possibly with a FWD car.


That aside, the only real advantage I can see that FWD cars have over RWD cars is overall stability, because FWD cars are prone to understeer, and thus they're not keen on having their rear ends hanging out in corners. And this is especially prevalent in races with slippery conditions or off-road courses.

I don't think you understand the physics of a FWD car. Understeer only occurs when you literally don't bother slowing down sufficiently. RWD cars can understeer too. The hardest thing in a FWD touring car is not losing the car, since for the first few laps, all it wants to do is spin. They have all their grip at the front, and no weight and cold tyres on the rear - when you turn in/brake and there's a weight shift, you're backwards before you know it.

Another hard thing is setting up the cars up to have lateral grip without understeer; hence why extreme rear camber settings were eventually run on SWB S2000 cars:

 

[Zenith]

I don't think you understand the physics of a FWD car. Understeer only occurs when you literally don't bother slowing down sufficiently. RWD cars can understeer too. The hardest thing in a FWD touring car is not losing the car, since for the first few laps, all it wants to do is spin. They have all their grip at the front, and no weight and cold tyres on the rear - when you turn in/brake and there's a weight shift, you're backwards before you know it.

There are many ways to get understeer.

 

[Bo]

When you watch NGTC cars on the limit, the FWD ones move around at the back a lot more - they're constantly sliding and wobbling. The RWD cars look more planted, but obviously, when you get a whack, there's only one you'd like to be in.

There was also something last year about rumours of Honda going full spool with the FWD setup to get exits as good as the RWDs.

 

[CyborgGT]

 

[MatskiMonk]

"The FWD drive guys just put their foot down and drag their arse end around the track, the BMW, you've got to be much more careful putting the power down at the limit"

That's what Mat Jackson said to me when I asked him about being back in a BMW BTCC Touring car a few years ago.

As for FWD cars and oversteer... yes I guess set-up and mods make a difference but lift-off over steer is not that hard to achieve in any FWD I've had, and they were all bone stock shopping trollies - but then most of the FWD cars I've had have had much narrower tyres and probably been lighter than the RWD German cars I've had since.

 

[Skygrasper550]

*grabs popcorn* honestly enjoying the discussion here and reading through the posts.

I can get my Neon fully sideways without the use of a handbrake and I've even spun it in a few corners due to oversteer. It really comes down to how the car is setup. I have a super beefy rear sway bar with stiff springs and struts which promotes oversteer.

I don't think having that amount of oversteer (which i think is too much) is not ideal in racing.

I don't think you understand the physics of a FWD car. Understeer only occurs when you literally don't bother slowing down sufficiently. RWD cars can understeer too. The hardest thing in a FWD touring car is not losing the car, since for the first few laps, all it wants to do is spin. They have all their grip at the front, and no weight and cold tyres on the rear - when you turn in/brake and there's a weight shift, you're backwards before you know it.

Another hard thing is setting up the cars up to have lateral grip without understeer; hence why extreme rear camber settings were eventually run on SWB S2000 cars:

I do understand how physics work on cars. I said that statement as a sort of generalization, in that in general, in all basic technicality, FWD cars are more prone to understeer than RWD and other drivetrains.

 

[Zenith]

It's worth noting when we use Touring Cars as anecdotes that the rules are designed to make entertaining and competitive racing, not the fastest cars.

If you want to look at some "no holds barred" setups, look at what tuners are doing. It's common to see significantly wider front tires than rear tires. This is partially attributed to the higher power being pushed out. When it comes to setup, the car is usually set nice and soft to try and keep as much momentum up through the corners as possible. Keeping that outside front tire nice and planted is a key goal.

The Mighty Mouse Time Attack car is great. Take note of how aggressive even the rear aero package is. Massive wing and undertray.

 

[Bo]

The Mighty Mouse Time Attack car is great. Take note of how aggressive even the rear aero package is. Massive wing and undertray.

Ex-F1 engineer designed. Similar stuff going on with the dar Leon in British Time Attack, albeit slightly less extreme.

 

[Joey D]

I don't think having that amount of oversteer (which i think is too much) is not ideal in racing.

Depends on the racing, rallycross courses are typically tight and on loose dirt. Without the proper setup any car is going to push to the outside when in the dirt and mud so having a tail happy back end that whips around makes it faster through the course.

 

[Exorcet]

Lower drive train losses for one.

This will only apply to FF vs FR (or AWD). MR should be just as efficient as FF since there is a similar amount of transmission between the engine and wheels.

I've never raced a fast person who liked understeer to oversteer. Slower drivers may like understeer because it gives them confidence, but at a high level a driver wants full control. Just look at pole position laps from any series, the car is on the edge of control for maximum speed.

Oversteer isn't full control though. From what I know the preferred set up is slight hint of understeer for controlability. Oversteer doesn't makes you any faster, your rear tires have lost grip and that's only going to slow you down.

I don't think you understand the physics of a FWD car. Understeer only occurs when you literally don't bother slowing down sufficiently.

Understeer is when the front tires exceed their slip angle limit before the rear, it's not speed related.

 

[Vegard]

This will only apply to FF vs FR (or AWD). MR should be just as efficient as FF since there is a similar amount of transmission between the engine and wheels.

Yes. But not many race classes see FF go up against MR though.

Also, the OP specified FR and AWD.

 

[CodeRedR51]

That said they're pretty poor on road courses.

Disagree. A properly set up FWD can tackle a road coarse with the best of them. This coming from someone who has plenty of experience in a FWD car on road coarses.