I agree Niki - I only ever use FWD in LFS because its so much more realistic.

Tris - In 1969 a number of F1 teams experimented with AWD. Mclaren, Lotus and Matra. The reason they wanted to develop AWD was because these systems had been so successful in Indy Oval racing in 68. Successful enough to be banned in 1970!

However, I don't believe these attempts failed because of inherent floors in the 4WD concept. Yes they had problems with weight and understeer but they never really had resource to address these problems. Matra and Lotus were both title contenders in 69 anyway and Mclaren were coming on strong. For this reason, resource was diverted away from the 4WD projects as developers were requried to work directly for the teams title challenges.

This coupled with significant aero and tyres developments at the time meant the benefits of 4WD were being negated anyway and the teams abandoned their projects.

The reason why RWD tends to be used more is because it is lighter and more compact, both very important things in a racing car.

Quote from tristancliffe :

An F1 team, perhaps Brabham under the ownership of Bernard Eccelstone, tried AWD on their cars, and the added weight and complexity at the time made it absolutely awful. The drivers hated the way it drove. In fact, if I remember correctly, it was only better out of very slow corners. RWD was quicker off the line (controlled wheel slip), faster through corners, better at braking and lighter.

Lotus tried it with the Lotus 63, which was one of Chapman's disasters, as it happened it came shortly after slicks and wings, before these there was a huge problem with putting power down so had a well sorted 4WD car been ready for the '67 season the next decade of F1 could have been very different.

Quote :

RWD was quicker off the line

Where'd you get that from? Maybe true for the Lotus 63 but certainly not for all 4WD single seaters. The Hepworth Special was a 1970s hillclimb 4WD special powered by a smallblock V8, it can still get faster split times off the line (it matters a lot on a 30 second hillclimb) than any of the 700+ bhp conventional modern 3.5 litre Goulds/Pillbeams.



http://www.ferrariownersclub.c ... ley_postcard/popup/10.asp

Quote :

I think the same would be true today, even with 'clever' 4WD.

Most likely with the current wide tracks and move towards lower power cars that will remain true, however, if we moved back to another generation of turbo cars with silly power outputs then 4WD could well be the way forward.

4WD would also be the way to go in hillclimbing today, I can't find more photos or more than this little snippet on it but Nick Mann's front engined clubmans style special really shows the potential for 4WD in hillclimbing.

Quote :

I had been chatting to Nick Mann earlier, and luckily I had the chance to watch his home made four wheel drive single seater perform two practice runs. The car features a Ford BDA Turbo engine, only 1700cc, but it punches out between 400 and 500 BHP. The Turbo isn't spun by the exhaust gasses though. Its spun by a Helicopter gas turbine engine which is started by his helper after he's coaxed the BDA in to life. Nick went on to set FTD in his Mannic/Beattie car

In F1 they started experimenting with awd because the engines were powerful enough so they were having difficulties putting all the power to the road. But the tires got better and aerodynamics got better so there wasn't actual need for such system anymore. Putting an awd system on modern F1 car just makes it too heavy. The TCS does it better than awd. And less parts to break = less worries = less problems.

EDIT: I just read ajp's post and he already said the same thing, d'oh.

Quote from Gentlefoot :

This coupled with significant aero and tyres developments at the time meant the benefits of 4WD were being negated anyway and the teams abandoned their projects.

As did I.

In relation to the last point - in most forms of motorsport, power, weight, aoreodynamics, tyre dimensions and other technical specifications are limited in some way. So I would say, in order to fully understand the benefits of AWD you would need to test the configuration in an un restricted form of motorsport.

Does anyone know of such a series?

My guess is that in such a series AWD would dominate. I know, I'm asking for it.

f1 cars currently have a minimum weight specified, yes? so awd is unlikely to increase the weight at all, just means the weight balance is not as adjustable.

Quote :

In relation to the last point - in most forms of motorsport, power, weight, aoreodynamics, tyre dimensions and other technical specifications are limited in some way. So I would say, in order to fully understand the benefits of AWD you would need to test the configuration in an un restricted form of motorsport.

Does anyone know of such a series?

Hillclimbing/sprinting has very few rules, I think fuel is restricted to normal safe racing fuels (none of the old highly canceragenic special brews) and nitrous is now banned.

Quote from Blowtus :

f1 cars currently have a minimum weight specified, yes? so awd is unlikely to increase the weight at all, just means the weight balance is not as adjustable.

You can't make a 4WD F1 car, or do much at all due to the restrictive rules. As for weight yes it is specified but racing cars are always built as light as possible and then ballasted up to acheive a low centre of gravity, you'll probably find that around 200kg of a 600kg F1 car is ballast.

Ferrari have about 105kg ballast from what I read (Mr Piola, the clever journalist).

Quote from ajp71 :

You can't make a 4WD F1 car, or do much at all due to the restrictive rules. As for weight yes it is specified but racing cars are always built as light as possible and then ballasted up to acheive a low centre of gravity, you'll probably find that around 200kg of a 600kg F1 car is ballast.

Yes... that was my point

Quote from ajp71 :

Hillclimbing/sprinting has very few rules, I think fuel is restricted to normal safe racing fuels (none of the old highly canceragenic special brews) and nitrous is now banned.

That's not actually true. Hillclimb and sprint events in the UK are goverened by MSA regs. Also, there are several classes all subject to various restrictions. Eg Road Going Production Modified under 2000cc. In this class, you must have all interior in place, the engine and transmission must be a derivative of the original. i.e. you can't switch a 2WD to 4WD or 16 valves from 8 valves, or put a 3.5 litre Rover v8 in a mkII Golf.

However, the sports libre classes are designed as a catch all for cars that are not eligible for other classes. Even this class is restricted to some extent though. Cars are subject to minimum weight and size, tyre softening compounds and warmers are banned and there are many other rules I am unaware of I'm sure.

250bhp Limited on FWD, not quite right. Late 90's early 2000's the BTCC cars ( Vectra's and Mondeo's ) had 300bhp they was all FWD. Same as todays BTCC, all FWD except 1 new entry, the new BMW and thats RWD.

4WD Racing ( not Rally ) cars do benefit. Look at Audi and Frank Biela. Audi Dominated the BTCC, and thus 4WD got banned.

Whether its FWD or RWD or AWD. It all depends on the driver and what they prefer. I prefer FWD, but thats just me. Regarding LFS, Niki hit the note. FWD is more realistic due to the bugs, but once these bugs are removed, then I think we might see from dedicated FWD drivers converted

Quote from Fordman :

250bhp Limited on FWD, not quite right. Late 90's early 2000's the BTCC cars ( Vectra's and Mondeo's ) had 300bhp they was all FWD.

The motoring press's 250bhp "limit" figure (not that I agree with it particularly) is for road cars, there are, have been and always will be fwd race cars with more power than the most powerful fwd road cars. But put 300bhp through the front wheels of a road-spec Cavalier SRi and the result would not be as pretty as it was with Cleland's championship winning car

Quote from Fordman :

Same as todays BTCC, all FWD except 1 new entry, the new BMW and thats RWD.

That's only down to rules. If the allowed amount of power rose to 500bhp then the fwd field would have no hope and fade right away. Similarly, if the field could modify the configuration of their cars without penalty, few (if any) would keep them fwd, but with just 250bhp, I doubt any would bother with 4wd.

Quote from Fordman :

FWD is more realistic due to the bugs, but once these bugs are removed, then I think we might see from dedicated FWD drivers converted

Just different bugs. Doesn't the essential locked-diff and bizarre slight power-oversteer bother you at all? FWD cars certainly are no more realistic in LFS, but perhaps because they're much easier to drive their deficiencies are less obvious.

Quote from sinbad :

Just different bugs. Doesn't the essential locked-diff and bizarre slight power-oversteer bother you at all? FWD cars certainly are no more realistic in LFS, but perhaps because they're much easier to drive their deficiencies are less obvious.

As Sinbad said FWD cars are not realistic in LFS, with a locked diff you would be unable to go round corners IRL because they'd simply rip themselves to pieces (assuming you were strong enough to turn the wheel in the first place).

Quote from Gentlefoot :

However, the sports libre classes are designed as a catch all for cars that are not eligible for other classes. Even this class is restricted to some extent though. Cars are subject to minimum weight and size, tyre softening compounds and warmers are banned and there are many other rules I am unaware of I'm sure.

What I was trying to say was that there are free single seater classes (which is unusual as normally open wheeled cars don't race in all comers races like closed wheeled cars do) obviously they still have to follow the MSA safety requirements and the odd specific rule set by the hillclimb club.

As for a Rover V8 Nick Mann competed his Morris Minor in the modified production car class as did Hannu Mikola in his Audi, although the rules may have been tightened since then.

Well, BTCC had them all IIRC some years ago.. 4WD audis, RWD beemers and loads of FWD cars. I seem to recall the audis being good in the rain but 'close but not quite there' on dry stuff, and slower on the straight.

FWD and RWD is close in speed but if you are a bit like Tiff Needel, i.e. enjoy controlling cars near the limit, you'll curse everything that is front wheel drive as you can't play with them. And even racing, you don't get that 'balance the nose direction with throttle' with front wheel drive.

If racing was all FWD, I wouldn't be into simracing. The pure challenge of car control imo is only possible with RWD. FWD is more about being very clean and precise. Of course RWD is that as well but sooooo much more interesting. The right foot steers the car (well.. ish)

if you're going to judge the capability of drivetrain layouts, you really need to use something other than parity modified racing

i once experience quite savage oversteer in a customers mg metro turbo once due to a faulty rear suspension bush giving an unwelcome rear wheel steer effect. quite terrifying as it wasnt expected, he had just said it felt funny when driving reasonably fast and asked me to go for drive in it. i ended up on a long left hander with the rear end out being unable to lift off in case it went round on me and with a right hander coming up straight after the bend. fortunatly i had a 100 meters or so of straight to slow it down

Quote from himself :

It is known that FWD can not have more power than 200 - 220 bhp.

Quote from Jakg :

for a ROAD car the limit is 250 with proper suspension...

Where do people get these strange ideas? Have they not driven FWD cars before or do they read somethign that someone wrote 30 years ago based on false assumptions and assume it to be true today?

There are plenty of production FWD cars that have been available over the past 15 years with 250-300 HP. There are a lot of daily driven, modified FWD cars that have more than that. Even back in the 1960's Oldsmobile had a 425 cubic inch displacement(7.0 liter) FWD V8 car with 385 bhp (287 kW) and 475 ft·lbf (644 N·m) of torque.

I've driven modified FWD cars that put down 300 to 400 HP at the wheels acordign to a dynojet dyno and not a single one of them was difficult to drive or a problem to drive in an autocross or tight road course. They also behaved very well on the street and some weren't much different in daily driving than the same car with stock horsepower.

One of the high horsepower FWD cars I helped build won 1st place in Car & Driver's superfour challenge and about the same lap times as a forced induction lotus elise.
http://www.caranddriver.com/ar ... d=10165&page_number=8

As the article says, "With all that locomotive torque, we expected a wrestling match at the steering wheel every time we tramped on the gas. But that wasn't the case. There was a little tugging in the first three gears, but nothing to rival the antics of the two boosted Civics, and no worse than a stock SRT4."

Quote from Niels Heusinkveld :

FWD and RWD is close in speed but if you are a bit like Tiff Needel, i.e. enjoy controlling cars near the limit, you'll curse everything that is front wheel drive as you can't play with them. And even racing, you don't get that 'balance the nose direction with throttle' with front wheel drive.

You can set up a FWD car's suspenstion to be steerable with the throttle at the limit. You can also get FWD cars to behave like RWD cars. My FWD daily driven car that I also use for autocross has lift throttle oversteer and also can be guided with the throttle aorund turns depending on how I drive it. The suspension is 100% stock except for th rear sway bar, which is thicker than stock. FWD cars can be played with on the track, you just have to know how to set them up.

sorry, but the bit about fwd cars behaving like rwd is as much misguided rubbish as the first poster

Quote from Blowtus :

sorry, but the bit about fwd cars behaving like rwd is as much misguided rubbish as the first poster

I didn't say they behave 100% exactly liek RWD cars, but if you disagree, you have not messed around with the suspension on a FWD car.

if you think oversteer is what defines 'behaving like a rwd' then you lack an understanding of vehicle dynamics in general

Quote from tristancliffe :

An F1 team, perhaps Brabham under the ownership of Bernard Eccelstone, tried AWD on their cars, and the added weight and complexity at the time made it absolutely awful. The drivers hated the way it drove. In fact, if I remember correctly, it was only better out of very slow corners. RWD was quicker off the line (controlled wheel slip), faster through corners, better at braking and lighter.

I think the same would be true today, even with 'clever' 4WD.

Yet even in its awful, unrefined form it won a race, IIRC.

Also, I do believe they were using either a locked center or locked front diff. Obviously that would explain the unpleasant handling bits. To say that modern traction control and modern differentials offer much more is an understatement.

Whether or not "clever" 4wd will be faster depends entirely on the set of regulations. Mandated low power makes it less viable, mandated small grooved tires makes it more viable. It would be rather fun to see. Its really unfortunate that the golden days of competition for the technical sake of it have been more or less replaced by spectator sport with controlled costs and huge rules packages.

But what sort of sport are we talking about people?
If it's circuit racing,
I have seen ff cars have a good run, the problem is they use their front tires to accelerate, brake and corner so their front tires wear quicker and understeer gets worse. Also they don't handle very well with too much horsepower. This is the main issue with ff cars even if their tuned to oversteer.
AWD cars have a lot of traction thus it's the fastest to take off at start, doesn't require much skill to drive especially the current evo's and sti's with their star wars technology, they can handle a lot of horsepower.
4WD's have come along way since the audi quattro, however due to current car manufacturer safety regulations these cars have gotten heavier and heavier(I mean the gallant vr4 was heavy, but these days the evo9 is just or heavier) Thats the only downside I can think off really besides power losses, but they are a really good platform for someone thats not experience with RWD cars. The Skyline GTR isn't a full time 4WD, I'll cover that later.
Sorry but like the FR AWD Lamborguini and others I don't no much about.

I'll cover FR and MR cars when I have the time, I have to go .

Quote from Blowtus :

if you think oversteer is what defines 'behaving like a rwd' then you lack an understanding of vehicle dynamics in general

Any car be it 4WD, FWD or RWD can have understeer or oversteer.

In most caes, only cars with power to the rear wheels can produce 'power oversteer'. However, even front wheel drive cars can experience power oversteer with certain setups and a diff under some circumstances.