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onegammyleg 09-18-2006 11:52 PM

Hi theclencher - ?How do you figure??

FWD cars only came about because its easier and cheaper for construction.
Sure , done rite they also give greater passneger compartment space as the trans tunnel is removed , although on cars that come in 4WD varient this is often not true.

In the beginning of FWD cars there was a few different engine transmision layouts tried.
The old mini was around as was the FWD Renaults (12) at the same time but the design ideas of both of those cars have been dropped.
The Fiat 128 was the first FWD car that was actually successfull and that plan is the basis for every FWD car to follow.
The engine was set east/west and had the transmision in direct line with the crankshaft.
The whole power plant assy was in front of the driver and between the suspension assy's.

Unfortunately --- This makes for wide cars.
Check out the figures for the track (between the wheels) for almost any 4 cylinder FWD car and then compare it to say a '70 MK1 ford escort.

I would bet a bag of peanuits that the escort was 20CM narrower than a Fiat 128 even tho it was a bigger car.

So . my beef with FWD is that most cars have a greater frontal area now days than they normally would (and push more air) have had if we had stuck with the RWD format.


PS . and in most FWD cars the height of the engine forces a high bonet line too., unles steh engine is layed back , A LOT. :D

onegammyleg 09-20-2006 03:42 AM

?I would not call Festivas, Metros, and old Minis "wide".?
They are if design progresion moves toward single inline seating streamliners.
Motro's are narrow because they use a 3cyl engine (not too good if you want to tow a boat) and old Minis were narrow becaiuse of archaic suspension designs and a combination transmision in sump arrangement , another idea thats been abandoned (in cars)

?If a narrower car were desired, a 2 or 3 cyl, or V4?
Both 2 ,3 and 4 cylinder engines dont have overlapping powerstrokes , so they tend to be less used because of vibrations.
V4 engines were mostly abandoned back in the 70's , they just dont work well.

?traction advantages of FWD are too good to be ignored?
FWD cars have far less traction on acceleration compared to RWD , havent you heard of weight transfer ?

?Also the drivetrain package is inherently more light, compact, and efficient?
Baloney - there is not much difference , and if manufacturers had been developing small RWD cars for the same amount of time they have been with FWD they would have dropped that weight- (eg , with carbon fiber prop shafts).

?the Subaru flat cylinder configuration while retaining FWD could be adopted?
Subaru's way only works because they use a flat 4 boxer engine (similar to the old VW beetle).
This means that the engine is not much longer than 2 cylinders.
SAAB used to do it also but with a 4 cyl engine and pointing backwards.
They have abandoned that idea.

In a typical family sedan (camry etc) with a real engine it dictates a wide engine bay.
It is possible to get a narrow FWD econo car , but it gets harder to do as the suspension has to go sumwhere.
I doubt auto manufacturers will ever go that route as it would force a whole revoltuion of what buyers will acept as a car - and I dont think average Joe ever will change.

I think he will walk b4 buying a 300cc streamliner.- and thats why these concept cars always stay just that.

red91sit 09-20-2006 05:30 PM

Quote:

Originally Posted by onegammyleg
Hi theclencher - ?How do you figure??

FWD cars only came about because its easier and cheaper for construction.
Sure , done rite they also give greater passneger compartment space as the trans tunnel is removed , although on cars that come in 4WD varient this is often not true.

In the beginning of FWD cars there was a few different engine transmision layouts tried.
The old mini was around as was the FWD Renaults (12) at the same time but the design ideas of both of those cars have been dropped.
The Fiat 128 was the first FWD car that was actually successfull and that plan is the basis for every FWD car to follow.
The engine was set east/west and had the transmision in direct line with the crankshaft.
The whole power plant assy was in front of the driver and between the suspension assy's.

Unfortunately --- This makes for wide cars.
Check out the figures for the track (between the wheels) for almost any 4 cylinder FWD car and then compare it to say a '70 MK1 ford escort.

I would bet a bag of peanuits that the escort was 20CM narrower than a Fiat 128 even tho it was a bigger car.

So . my beef with FWD is that most cars have a greater frontal area now days than they normally would (and push more air) have had if we had stuck with the RWD format.


PS . and in most FWD cars the height of the engine forces a high bonet line too., unles steh engine is layed back , A LOT. :D

We've arleady covered the width thing, so i'll move on the the high bonet line. Ever seen a 1988-1991 Honda Prelude? I'm 5' 4" and my knees were above most of my hood, and yes it was FWD.

Now look at modern cars, wow the hoods a lot higher! Not because the motors are larger, it's more for the safety of pedestrians. Yup, that's right something about having a higher hoodline makes vehicles safer for running into people. I'm 90% sure this is a new goverment regulation.

Weight? how can you argue this one?

FWD - Transmission, Intergrated differential housing, CV's
RWD - Transmission, Driveshaft (with power sapping joints), differntial and mounts, CV's

Even if the driveshaft didn't weigh anything, the RWD would still be heavier due to the differential and the beefed up area holding it.

Traction? I don't hear a lot of people complaining about burning out all the time. ha ha. In winter weight transfer can't beat weight already there, and FWD are a lot easier to maneuver. (just talk to any S-10 owner about that one)

Balance? lawyers know understeer is safe. Going backwards? not so safe.

Tradition/Average Joe? if this was the case everyone would still be driving RWD, V-8, carb'd, boats (like me :p) If we do get them to buy streamliners? I"im sure they'll be just as wide as a motorcycle, which conveniently use horizontally opposed 4 cylinders :) Which would make a great drive line for a 2 seater tandem sporty "streamliner" Unless it's going to be skinnier than a few feet wide. But then it would pretty much have to be a motorcycle again.

Now we CAN stick the motor in the back MR-2 style, but this really doesn't have any advantages compared to being in the front. (economy wise)

I don't mean to argue, I'd like to hear your counterpoints, but please make sure they are correct.

I attached a picture of the prelude,

https://memimage.cardomain.net/member...5_151_full.jpg

The hood could not be any lower because of the 14 in. wheels, not the motor. Stick some 12's on there and you get a very ugly car, AND a lower hood :)

JanGeo 09-20-2006 05:42 PM

Well my xB is really tall in the hood area and the oil pan is about as low as anything on the bottom and the engine cover is pretty close to the hood but it is not very deep so the hood is short with plenty of crush zone between the engine and fire wall. The Geo was a low hood so low in fact that you couldn't see it when sitting in the car which made steering really weird and finding light poles while parking some what damaging to the bumper. One good thing about FWD is that the entire drive train gets warmed up rather quickly by the engine and there are less seals that can go bad - anyone ever drop a drive shaft in a rear wheel drive car, have a leaky tranny seal or blow a universal joint? Width is engineering and better for stability.

omgwtfbyobbq 09-20-2006 06:13 PM

Yikes, no need to go that far theclencher. Besides, stating that auto design is based on engineering limitations is kinda ignoring all sorts of consumer demand issues.

red91sit 09-20-2006 06:57 PM

anyways, back to the topic, what if you placed a thin ramp thing right before the flaps? that way the air won't try to get between the flaps and the fender it will go up over it, perhaps a few squares of velcro to help keep it closed as well?

onegammyleg 09-20-2006 10:51 PM

Hi theclencher - ?Narrow high FE FWD vehicles are not only possible, in many cases they are the most sensible layout.?

Really ?! ..well , explain how using conventional engine components (as we know it) are going to fit a FWD engine and gearbox assy into the 1L/100k Volkswagen concept car.
Its going to be hard considering the whole vehicles width is less than the length of say a Camry engine and gearbox at 1.25m.

So your assuming that manufactureres will continue with boxfish style bodies instead of streamliners.
This might be possible to do and use some conventional compontnets , but will they get supermilage from them , not likely.

The Mercedies boxfish FE car isnt all that FE.
?In the EU driving cycle the concept car has a fuel consumption of 4.3 litres per 100 kilometres? (average)

All that I have stated was that if auto manufactures try and keep cars in a similar style to what we have then it is unlikely that super high FE cars will be produced any time soon.
Super FE cars can not come from evolution of a design principle that has always had a disregard of fuel consumption.

In my view auto design has gone down the wrong road , and to change directions they will have to rethink a lot of what they have done.

JanGeo 09-21-2006 04:16 PM

Oh I totally agree that conventional auto design will not get us to the "high" mileage vehicles we expect. I don't expect the auto industry to be able to change tooling and design concepts in the near future so it will be up to new small companies to impliment the change and build the next generation of vehicles as well as the weekend garage car builder!

onegammyleg 09-21-2006 10:59 PM

Hi JanGeo .. I agree with your message :)

BUT- ?so it will be up to new small companies to impliment the change and build the next generation of vehicles?

Unfortunately that wont happen.
If you havent already seen it - Go to the video store and rent out ?Tucker?
Its the true story of a small car manufacturer that tried to make a differnece by making advanced cars.
The big auto manufacturers squashed him.

It happend b4 , it would happen again.

Ime not a pesimist , but the little guy cant win in a society that is driven by profit and greed.
We will get high FE cars only when the auto manufacturers can see a profit in it.
The state of the worlds environment and public opinion has nothing to do with what car makers make.
They make what they can get a good profit margin on and to tool up for a totally new idea would cost too much (to them)

I think the story will go ?Yeah we tried these economy cars but coudlnt make them reliable? or something like that , some lame exscuse.

And a typical US buyer (like theclencher) that has no idea will suport the auto makers in keeping the big cars.

Here in my country there are no big cars (my metro is classed as a little smaller than normal family size) , so we are likely to adopt real FE vehicles many years before America does.

In my country of birth we were trying to start a company making replica Lous 7's.
I submitted about a years worth of devolpemnet in engineering work to the government and finnaly got there OK to build them.
Although they gave the Ok they did put one eeny weeny clause on it.
That was that my company would be perpetually liable for accidents involving my car.

So we went to the lawers and it was impossible to get around , to be forever liable for something not under your controll.
Insurance costs would effectively double the price of the car., thereby making it unsellable.

Even if it would be possible for a backyarder or small manufacturing company to build a new FE car , it will never be possible due to government restrictions., and likely it would never hit the road.

Thats life.

onegammyleg 09-21-2006 11:36 PM

Hi theclencher

Hey , but you said before ?more light, compact, and efficient' , now you changed it to ?are more compact and integrated, you simply cannot deny it?

Those two statements are totally different.

We were talking about FWD and the area of the engine and transmision is very similar to that when used in a front engined RWD format.
The only difference is the space and weight required for a connecting prop shaft down to the rear end., and a litle extra for the diff's axle tubes.(which the same amount of material is often still found in the rear suspension of a FWD car- no saving here)
With modern materials the difference in weight is minor., and with a front engine rear drive format it allows more flexibilty in design over FWD vehicle as we know it.

Just because the engine and transmision are at the front end of the car doesnt make them in any way more efficient.
An effiecent use of space maybe , but this is with THAT adopted body design , if you use a radically different body shape or style and that advantage is gone.


?it has more in common with Super-High Mileage Competition vehicles than regular cars.?
Well ..if the majority of car buyers have this view then there is no hope.
If we are stuck with conventional format vehicles then there is very little room to advance.


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