: So what's wrong with FWD?



mtflight
06-08-05, 12:33 PM
Tradition
Sure, traditional cars--especially ones that claim to be sporty/touring--are RWD.

Weight Distribution
But, I think the weight distribution from front to rear is not THAT bad on the later FWD northstars... they do drive very well too.

Fuel Economy
It is my observation that RWD cars take a fuel economy hit as well.

Snow Belt/Rain Traction
I'd rather be in the rain/snow in a FWD car, than in a RWD car... sure now there's AWD, and traction control etc... but those take a greater fuel economy hit.

Engine Bay
Yes, this is a big one. It seems as if though it was not necessary to mount the Northstar sideways in the Deville, Seville, and Eldorado, but because the Northstar was also designed to fit in the Allante... the 4T80-E was designed with a T instead of an L... too much money involved in reengineering it just to mount it traditionally. Up until the smallish Cadillacs of the late 80s, the FWD car engines were mounted the traditional way, not sideways.

Thanks to the sideways installation, we have the nightmarish repairs such as blower motor and headgasket repairs which require the engine be dropped from the car.

I would say, that if the FWD car stays, it would be a nice touch to put the engine in longitudinally (sp?) vs transversally (sp??).

I remember my grandpa saying the transversal mounting was "junk." He was referring to service issues.


So guys what's the consensus? Am I thinking like a dinosaur? Did I miss the train? What's your take on it? I look forward to your replies.

caddydaddy
06-08-05, 01:13 PM
For an everyday vehicle, and foul weather, FWD is best. (of course all wheel or 4 wheel is superior to both)
I love how good my '94 Deville is in the snow, but all the old 70's RWD Caddys I've had sucked in snow, even with snow tires!
For performance, RWD is best.
For ease of maintainance, RWD is MUCH better!

davesdeville
06-08-05, 05:31 PM
When you launch the car, the weight transfers to the back wheels. In FWD cars this means you lose traction. Also the weight distribution is drastically better in a RWD car so they handle better (XLR is about 50/50, but a 98 STS is 62/38.) This is why RWD is best for performance. Some argue AWD is best for performance, but the extra weight usually makes up for the great launches AWD cars can do.

Transverse mounting makes it a pain in the ass to do anything on the rear bank of cyls. Even simple spark plugs can be a big pain.

The ONLY thing FWD has going for it IMO is that it's better than RWD in slick road conditions, but AWD is the best for those conditions anyway. In conclusion, buy RWD if you live in a dry place like I do or go AWD if you get a lot of snow.

Ranger
06-08-05, 09:46 PM
I agree, I miss the "North/South" oriented engines (the way God intended them).

JimHare
06-09-05, 11:41 AM
When you launch the car, the weight transfers to the back wheels. In FWD cars this means you lose traction. Also the weight distribution is drastically better in a RWD car so they handle better (XLR is about 50/50, but a 98 STS is 62/38.) One would assume that in a FWD auto, a forwards-biased weight distribution would be preferred, would not one? Keeps the drive wheels on the ground. This is one of the reason why FWD cars tend to be better on snow than RWD cars - the majority of the weight is over the drive wheels.

Let's face it, the only real reason that car nuts don't like FWD is that it's tougher to do a wheelie in one.. LOL

EcSTSatic
06-09-05, 12:18 PM
For chugging thru snow FWD works best. For anything else RWD rules.
see Rear-wheel drive making comeback (http://autonet.ca/autonetstories/stories.cfm?storyID=11557)

BeelzeBob
06-09-05, 04:25 PM
What with RWD "making a come back" it is interesting to read all the comments in various forums and in the press regarding the "sudden" need for snow tires in the winter.....LOL LOL LOL

There is a whole generation of drivers that have grown up with nothing but FWD cars and they seem to be mystified by the fact that the RWD cars cannot go in the snow without snow tires. Amazing.

I think that the more people that get into and drive RWD cars the more of them that will suddenly "discover" the advantage of FWD that they never realized.

Even on this forum if you read thru some of the STS comments in the RWD STS section there were comments about how "bad" the cars are in the snow and how one individual wrote Cadillac expecting an explaination as to why the STS with performance tires is not as good in the snow as his previous (FWD) STS....LOL LOL Guess what...???...that is the way RWD cars have always been, especially when you put wide performance tires on them.

That is basically it.

FWD cars will never be ultimate "performance" cars because of simple physics...you are applying power thru the front wheels and creating turning loads thru the front wheels and there is only so much tire grip to go around....so a FWD car can never turn and apply power as hard as a RWD car...i.e....you are never going to see a FWD F1 car.

For pure racing and pure performance work the RWD cars will always be capable of higher ultimate performance levels.

For every one else for everyday driving FWD is very very hard to beat....and more people will be discovering this as they migrate to the RWD cars that the motoring press has convinced them that they needed and wanted.


The real answer to the question is that there is no real answer to the question. There is no "best" car. It depends on what you want to do with the car. If you want a car to drive all the time in all weather then FWD is clearly superior. AWD works, yes, but complexity, cost, mass and fuel economy penalties tend to make AWD a runnerup to FWD for all-round best performance.

If you want a street racer/cruiser....RWD is it. If you want a track car or drag car...RWD is it.


If you really want an eye opener drive a Pontiac Bonneville GXP (which is FWD) . It handles with all but the very best of the RWD cars and still goes in the snow...wide tires and all. The new Pontiac GrandPrix with the 5.3 V8 is certainly the best of the FWD cars in terms of absolute limit handling capabilities combined with the advantages in foul weather of FWD. That car even has wider front tires (than the rears) to help overcome the inherent ability to overload the front tires. It handles amazingly well on dry pavement and still goes in foul weather.

mtflight
06-09-05, 04:51 PM
Wow. Drive-by-wire and a perfected 8-6-4 concept.

I should've driven those at the Auto-show in motion, instead I drove all the Caddies, Bimmers, GTO and 'Vette....

At least i wasn't the only one testing the limits of these cars on the mini-course (responsibly)... some guy got kicked out for spinning-out a GTO (!)....

What kind of differences between say a DTS vs. GXP, in terms of ride and handling (CVRSS vs ??)... similar N* and 4T80E. I like the more snarly sound of the GXP (I heard it while waiting to drive the GTO).

Spyder
06-09-05, 05:40 PM
And why are wide tires bad in snow? Simple question, but it seems to me like more footprint is better for traction...?

Vesicant
06-09-05, 05:57 PM
And why are wide tires bad in snow? Simple question, but it seems to me like more footprint is better for traction...?

I was told and always figured it like this: You want to cut through the snow and reach traction on the ground - kinda like a knife; it transmits to the road surface quicker.

Whereas for sand/mud you want to float and roll over with a wide surface area so you dont sink in. You'll just dig deeper because theres nothing below to aid traction.

BeelzeBob
06-10-05, 01:00 AM
And why are wide tires bad in snow? Simple question, but it seems to me like more footprint is better for traction...?


Wide tires tend to "hydroplane" on top of the snow...if that is the right use of that word. Wide , performance tires with narrow tread grooves ride up on the snow, pack it into ice and cause loss of traction.

For snow you want skinny, tall, heavily lugged tires to dig down thru the snow to the hard pavement below. Plus, the narrower the tire the less tendency to hydroplane in the snow and slush.

Wide aggressive performance tires can still work quite well in wet/rain conditions as they can flow the water out of the way and the performance tread rubber compounds typically are not too bad in the wet. But, in snow, they can be abysmal. They just roll up on the snow form ice and slip and slid. The tread grooves are too narrow to dig in and the wide tire patch makes a very low specfic pressure point so it is easy for the tire to ride up on the snow. You want very narrow tires with high specific loading so that the snow cannot support the weight on the small contact patch and the tire will dig down thru it.

FWD cars will negate some of this effect, however, as the higher loading on the front tires will allow them to dig thru the snow even if they are somewhat "wide" since the loading is quite high on the drive (front) tires.

As an example, I used a GXP to tow my snowmobile trailer up into northern Ontario three trips last winter...wide tires and all. Then I autocrossed the car in a spring autocross. Nothing like the all 'round performance capability of a FWD car for the masses.

etcCanuck
06-10-05, 01:11 AM
Whereas for sand/mud you want to float and roll over with a wide surface area so you dont sink in. You'll just dig deeper because theres nothing below to aid traction.

Im not sure of that either, military trucks always have very narrow tires. I think the force/square inch works to their benifit...

JimHare
06-10-05, 06:33 AM
Back in the winter of '71-'72, it snowed one day all day while I was at work. By the time I got out at about 3:30 or so, there was probably 18-20 inches on the ground. There was no way I could have driven back to my house 6 miles away across hill and dale, but a good friend lived about two miles from work across relatively flat roads. I arranged to drive to his place to stay instead. His house was about 3/4s of the way up a rather steep hill, (we're talking about a 30% grade) and when I got there, his street had not been plowed. I tried about three or four time to get up the hill but the old Plymouth Fury II station wagon just spun it's rear snow tires after about 20 feet up the hill and I slid back down. I tried another tactic. Turning around at the bottom, I put her in reverse, and BACKED right up the hill without even loosing traction. Don't ask me why, but for some reason, having the wheels up front PULLING the car rather than in the rear PUSHING it, made the difference. Ever since then, I've been sold on the advantages of FWD for non-optimum road conditions... LOL

:yup:

caddydaddy
06-10-05, 08:07 AM
Even on this forum if you read thru some of the STS comments in the RWD STS section there were comments about how "bad" the cars are in the snow and how one individual wrote Cadillac expecting an explaination as to why the STS with performance tires is not as good in the snow as his previous (FWD) STS....LOL LOL Guess what...???...that is the way RWD cars have always been, especially when you put wide performance tires on them.


LOL, my 2000 STS absolutely SUCKS in snow! But at least I had more common sense than that guy to realize that it was the V-rated performance tires that made it horrible to go, stop and turn! Stabilitrak was mad at me that day!
On the other hand, my '94 Deville with all season narrow 15" tires, is awesome in the snow!

BeelzeBob
06-10-05, 05:21 PM
Im not sure of that either, military trucks always have very narrow tires. I think the force/square inch works to their benifit...


Wide tires do work best in sand and soft surfaces.

Miltary vehicles need to go anywhere and the narrow, heavily lugged tires work on most paved and hard surfaces (roads of any sort) in most any weather which is their first mode of operation.

The alternative in sand is to let most of the air out of the tire to increase it's footprint for added flowtation.....ever notice the funny looking wheel hubs on HumVees..?? It is the onboard, on-the-fly tire inflation/deflation system to allow the driver to drop the tire pressure for sand and soft road conditions. It is pretty much the trademark of the HumVee and is available on the civilian version of the H1. Look at the H2 wheel center caps...notice the design with the asymetrical bar across it..?? It mimics the tire inflation/deflation system seen on the H1.

So, you are correct, on-road military vehicles do have relatively narrow tires but incorrect in assuming this proves that narrow works in sand. They have the ability to drop tire pressure for sand and soft surfaces because wide tires do work best then...per the tire deflation system on the H1 which is most likely to go off road per it's design. That system is one of the reasons the H1 or HumVee excels so well in it's mission.

dkozloski
06-14-05, 08:33 PM
As with just about any discussion involving cars and traction in snow, the biggest factor is the ability of the driver. More than once I have seen a car spinning helplessly in the snow only to later charge up the hill with a different driver. My college physics professor was known to issue a failing grade to a student after he observed him spinning the wheels trying to get going on the ice on the grounds that he failed to understand the concept of static versus dynamic coefficient of friction. A thinking driver can handle almost any car in bad conditions and a clumsy one wouldn't make it with an Oshkosh(residents of the northern tier will recognise that name). I prefer FWD for travel in deep snow. FWD is the registered trademark of Four Wheel Drive Corp. which makes huge off road trucks. Short of that, my '04 CTS on RSA's has never let me down over some of the worst winter conditions to be found in North America. Throw about four sand bags in the trunk and drive anywhere you want to go. It'll push knee deep snow. I just can't tolerate the inherent understeer in front wheel drive cars.