RWD -vs- FWD

DP944 · 12-16-2005, 11:04 PM

I have been arguing with my buddy over this for about two weeks and have gotten a lot of different opinions from a lot of different people. We added drinking to the arguments a few times and it got dangerous. Someone help us out. Which handles better? And I know....the wise tech will tell us that there are many factors that determine how well your car handles....but beside all of that....which, theoretically is set up better for racing and high speed drivability in and out of the good ol' twisties. My friend says that FWD is better, but something tells me that he assumes this because in Gran Turismo 4, for playstation, it is harder to spin out in a FWD car when you brake late then in RWD....I kind of figured that RWD is better for racing and has superior handling because the majority of racecars have power in the rear. Plus....steering, acceleration, and braking are all being relayed to two front wheels as opposed to four in FWD. Im sure that at lower speeds like autox'ing FWD is good for racing because not as much power is being relayed to those wheels so it is easier to maneuver. It just seems to me that if you distribute all the forces between four wheels as opposed to two the car has a more natural feel. You can almost slice through a turn in RWD, with your front wheels right in front relaying the rear wheels where to travel. It feels fluid...like a racecar should feel like. Let me know what you think. Thanks

-Pendleton

Eldorado · 12-16-2005, 11:32 PM

it's easier for your rear end to kick out behind you in a rwd car if you're throttle happy... that said, if your rear kicks out i believe it's easier to regain control with a rwd car... BUT in a fwd car, if you lose traction, the whole car is pulled along with it and not just the back.....

from a traction standpoint, ie. in the winter and in slick conditions, i maintain you're better with fwd... you have the weight of the engine and entire front end over top of the driving wheels.... this, of course, is provided you're driving in accordance with the conditions... if you're driving like mad, you're screwed either way you go..

it's all a matter of preference... in *perfect* conditions, I'd say RWD.... it's better in the curves... it pushes the car when the front wheels steer.... it's much better, in my opinion, than having the front wheels do the driving and turning....

AA_Ezra · 12-16-2005, 11:44 PM

I would say rwd.. I'll beat um in any rwd car on turismo any day.. And besides.. Indy cars are rear wheel drive, nascar, alot of the lemanh's cars are to

.

pokey · 12-17-2005, 12:00 AM

Whichever has the better driver, all other things being equal. You can generally push a RWD a little harder in the corners, and keep it on the road easier if you push it a little too far...

Lawrence Coppari · 12-17-2005, 04:22 AM

If you look at the weight restrictions on touring car racing, the 4 wheel drive cars must weigh most, the RWD cars are in the middle while the FWD cars can weigh the least. The rules are like this to compensate for the inequality of designs. Given equal weights and power/torque, and a dry track, 4 WD would always win, RWD comes in second, and FWD comes in third.

In the snow, FWD is better than RWD. In the dry, RWD is advantageous. When conditions are good, you are asking the front wheels to do double duty - accelerate and steer. I believe someone already mentioned this.

speedracing944 · speedracing944's Garage

AWD has higher drivetrain loss than RWD so what you gain on the launch and exiting out of the corners you lose on the top end. With AWD you can usually power out of the corners harder because you have more traction availiable and if the car is set up right like the EVO you can get nice throttle oversteer which is easy to control.

Speedy

Dave L · 12-17-2005, 06:22 AM

A tire only has so much grip either side to side or front to back. With FWD accelerating out of a corner you are trying to maintain grip side to side and produce acceleration. with RWD the front tires only need to provide the side to side grip while the rear tires provide the accelleration.

In the winter FWD is safer for the average driver because the natural instict is to lift off the throtle when in a skid. When you lift on FWD the tires car regain traction with RWD you will swap ends if you lift. I drive the e30 bmw, which will punish you if you lift in a turn, even in the worst conditions because of the better control of RWD.

Tervuren · Tervuren's Garage

It honesly depends on what you are tryin to do. In high power applications in a light weight vehichle, I'd prefer a RWD car for sure. But say, in a light car with a mostly fowards weight balance, FWD can suddenly become a very exciting drive. Such as modified mini's, etc.

There are quite a few FWD's I'd be quite happy to pilot. Most of them though, are not as availible on the American market. Of course, the car I realy love, si the Porsche 944, so I'm fairly biased to a RWD setup!

Porsche-O-Phile · Porsche-O-Phile's Garage

I'm old-school - I have to be pushed, not pulled.

Plus, cars with the wide tires on the front look absolutely idiotic.

A FWD car doing a burnout always makes me laugh - I don't care how much power it has, simply because it looks so damn ridiculous.

I also think a lot of it has to do with where the engine is. A front-engine car with rear drive would perform a helluva lot better than a rear-engine car with front drive. I think that should answer the question.

AaronM · 12-17-2005, 08:42 AM

All else being equal, RWD will handle better.

The reason is this: Tires have a finite amount of traction available to them. In a FWD design, the front tires must split their traction between propulsion and lateral traction. I know that the rears need to have some lateral traction to keep the back end in line, but the vast majority of the lateral traction is needed by the front (i.e. steering) wheels because they impart the force that causes the car to change direction. When this traction has to be split and used with propulsion as well, you lessen the available traction for both.

With RWD, the rear wheels can devote essentially all their traction to pushing the car forward while the fronts can devote all their traction to directional changes. Essentially with RWD you are distributing the traction load across all four tires in a more even fashion, while in FWD you are depending on only two tires. Even a FWD car with 50/50 weight distribution will understeer more (or oversteer less) than a RWD car because of this.

Your friend is right that FWD cars tend to be harder to spin out, especially in late braking because they understeer. But that's a driver limitation and not a really a benefit as almost all professional race drivers prefer to have their car set up for a little bit of oversteer.

Dantilla · 12-17-2005, 09:58 AM

Corvette.
Ferrari.
Viper.
Formula 1.
Nascar.
Pro-stock drag cars.
Top fuel drag cars.
Funny cars.

What do all of these things have in common?

Another question- When somebody wants to go club racing in a 911C4S, what do they normally do? Yup. Remove the front drive assembly.

Most "hot" FWD cars have their origins in some economy transportation machine, that morphed over time into something sporty. To design a true sports car from a clean sheet of paper, you end up with rear-wheel drive. Or more likely, you start out with rear-wheel drive.

Eldorado · 12-17-2005, 12:15 PM

Quote:

Most "hot" FWD cars have their origins in some economy transportation machine, that morphed over time into something sporty. To design a true sports car from a clean sheet of paper, you end up with rear-wheel drive. Or more likely, you start out with rear-wheel drive.

they both have benefits that can be exploited with experienced (and good) drivers.
it's a totally subjective opinion, I think.
you like what you like...

AaronM · 12-17-2005, 03:04 PM

Quote:

Originally posted by Eldorado
they both have benefits that can be exploited with experienced (and good) drivers.
it's a totally subjective opinion, I think.
you like what you like...

Sorry, but no. Some people may well be faster in FWD because they feel safer, but the basic physics involved dictate that, all else being equal, it is best to power the wheels that are not steering the vehicle. If the front wheels are steering the car, a RWD vehicle will be better at the limit.

That's not to say that FWD can't be fast. And it's not to say that FWD can't beat RWD when the rest of the setup is not equal.

Tervuren · Tervuren's Garage

Quote:

Originally posted by AaronM
Sorry, but no. Some people may well be faster in FWD because they feel safer, but the basic physics involved dictate that, all else being equal, it is best to power the wheels that are not steering the vehicle. If the front wheels are steering the car, a RWD vehicle will be better at the limit.

That's not to say that FWD can't be fast. And it's not to say that FWD can't beat RWD when the rest of the setup is not equal.

DUH! You don't design a FWD to be exactly like a RWD. The best FWD car's for an pliaction are not going to have the same setup. I think that would be common sense.

There are tons of variables. In my case, with my race car(Not the 944) FWD is horrible. The TOrque at the wheels is almost impossible to keep from excessive wheelspin - even with RWD. The suspension is not setup for FWD either, but is built for weight transfer to bite into the dirt on the side that needs to do the work. Make the front the driving wheels, and the weight shifts to the back, and you just spin tires and through dirt in the air. RWD isn't much better at low speeds, get too throttle happy and you power into nice tiny radius 360's. At higher speeds where torque at the wheels is less, its a very nice setup. I mostly run four wheel drive, which lets me push throttle through a corner.

I am wondering if we should also remove the brakes from the front of your car, as your front wheels eed to jsut do steering. Would it help? I think not.

FWD first came out on outright race cars, they allowed a lower center of gravity for better handling. Previously, you had to run things over the drivetrain that went to teh rear wheels. The fastest race cars back in years past where FWD at the Indy 500.

In higher horsepower applications, FWD starts to lose out a lot due to weight transfer. But in a car designed for smaller engines, it can be made to get around corners quite nicely. The problem, si when you have a driver driving a FWD likes its a RWD, they aren't getting the most out of it. Rally driver's tend wring more out a FWD then most. I've onyl driven them in sims or not in conditions to test the handling. I do love my 944's balance though.

Geo31 · 12-17-2005, 08:17 PM

Quote:

Originally posted by Tervuren
It honesly depends on what you are tryin to do. In high power applications in a light weight vehichle, I'd prefer a RWD car for sure. But say, in a light car with a mostly fowards weight balance, FWD can suddenly become a very exciting drive. Such as modified mini's, etc.

This is the best answer of the bunch.

I had been racing a FWD Sentra SE-R and you might be surprised how good FWD can be. A well set up Honduh with double wishbone can be even better. You must drive them differently and in some ways you can drive a FWD a bit more aggressively through tight corners.

It's not hard to set up FWD to oversteer. In many ways it's easier to control oversteer with a good FWD set-up. When the rear starts to rotate, all you do is mash the throttle and you can get a nice neutral drift. I have experienced this in a race. It's pretty amazing. Once you get the hang of it it can be quite fast. An LSD is a bit more important with FWD than RWD.

A good FWD set-up is probably easier to drive fast than a good RWD set-up for the average person. However, for those who can get the most out of their car, all things being equal I think RWD has a bit of an advantage.

I'd be careful dissing FWD cars if you don't really know what you're talking about.

BananaClip · 12-17-2005, 08:24 PM

sometimes cars are driven by the front wheels and sometimes they are driven by the back wheels
also sometimes they are driven by all four isn't that keen

AaronM · 09:27 PM

Quote:

Originally posted by Tervuren
DUH! You don't design a FWD to be exactly like a RWD. The best FWD car's for an pliaction are not going to have the same setup. I think that would be common sense.

There are tons of variables. In my case, with my race car(Not the 944) FWD is horrible. The TOrque at the wheels is almost impossible to keep from excessive wheelspin - even with RWD. The suspension is not setup for FWD either, but is built for weight transfer to bite into the dirt on the side that needs to do the work. Make the front the driving wheels, and the weight shifts to the back, and you just spin tires and through dirt in the air. RWD isn't much better at low speeds, get too throttle happy and you power into nice tiny radius 360's. At higher speeds where torque at the wheels is less, its a very nice setup. I mostly run four wheel drive, which lets me push throttle through a corner.

I am wondering if we should also remove the brakes from the front of your car, as your front wheels eed to jsut do steering. Would it help? I think not.

FWD first came out on outright race cars, they allowed a lower center of gravity for better handling. Previously, you had to run things over the drivetrain that went to teh rear wheels. The fastest race cars back in years past where FWD at the Indy 500.

In higher horsepower applications, FWD starts to lose out a lot due to weight transfer. But in a car designed for smaller engines, it can be made to get around corners quite nicely. The problem, si when you have a driver driving a FWD likes its a RWD, they aren't getting the most out of it. Rally driver's tend wring more out a FWD then most. I've onyl driven them in sims or not in conditions to test the handling. I do love my 944's balance though.

Umm, the Novis were successful because of their power, not because of FWD. Even the Offy-powered cars were RWD. And they dominated until the mid-engine/RWD cars came on the scene. Some of the early Novis were FWD, but none had more than 300 HP. In fact, more than one fatal crash in the Novis was listed as caused by terminal understeer.

Braking take traction away from all wheels equally, or at least, close enough to equally that the traction it takes away isn't material. Also, the weight transfer under braking increases traction available at the front wheels which offsets the traction used by the braking force. Your analogy doesn't hold.

FWD cars cannot be throttle-steered to the same degree as RWD cars and the steering will always have less feel. That's simply the way things are.

And to be perfectly honest, I fail to see how anything you've said contradicts anything I've said. I say that if all else is equal, RWD is superior due to the division of needed traction more evenly. You say that when things aren't equal, my claims aren't true. I've already said that. You've created a nice straw-man out of positions I don't actually hold, but nowhere have you contradicted anything I've said.

DP944 · 12-18-2005, 08:56 AM

ive gotten in a lot of heated debates over racing and cars in general....i knew this one would probably escalate a little bit hahaha.....my friend and i were ready to choke eachother. I like RWD.....I live in NH....snow + RWD = 360 degrees....its been done in FWD but not nearly as fun.... I also feel that RWD requires a little more skill because tiny little driver inputs can make a huge difference, not nearly as much in FWD.

-Pendleton

Geo31 · 12-18-2005, 09:30 AM

Quote:

Originally posted by AaronM
FWD cars cannot be throttle-steered to the same degree as RWD cars and the steering will always have less feel. That's simply the way things are.

Have you ever raced or seriously tracked a FWD car?

The two are just different. Both can be throttle steered, but that in and of itself does not a great car make.

As for the sterring feel, I think a FWD car has better feel. I have a much better feel for what the driven wheels are doing becaue have one more input for evaluation. In a FWD car on the limit I can feel real nuances in the traction.

Still I do that those with the very best of skills will get a bit more from RWD.

AaronM · 12-18-2005, 09:56 AM

Quote:

Originally posted by Geo31
Have you ever raced or seriously tracked a FWD car?

The two are just different. Both can be throttle steered, but that in and of itself does not a great car make.

As for the sterring feel, I think a FWD car has better feel. I have a much better feel for what the driven wheels are doing becaue have one more input for evaluation. In a FWD car on the limit I can feel real nuances in the traction.

Still I do that those with the very best of skills will get a bit more from RWD.

Again, I didn't say that FWD can't be throttle-steered, just that it doesn't have quite the range that RWD has for throttle steering. It's a matter of degrees, not absolutes. As I've said (I forget if it was here or in another thread), I've seen and driven some FWD cars that would almost certainly show their tail-lights to my 951 on a track. It's not that it can't be made fast or good-handling, just that I think there are a wider range of control options with RWD.

For me, FWD muddies the steering feel. I get a little bit better feel for propulsion traction, but I just don't get the same feedback for steering and whether the tires are going to break loose in steady-state that I do with RWD. FWD tends to dampen steering feedback because the what's best for preventing torque steer and what's best for preserving road feel as far as suspension design are at loggerheads. I've driven many FWD cars where the compromise is very well executed, but it's still a compromise. I just can't feel the road through the steering in FWD the way I can in RWD. Heck, I can't feel the road through the 951's power rack the same way that I can through the 914's non-power setup.