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Old 18th August 2009, 00:33   #16
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I doubt it has much to do with FWD or RWD.

Even on a flat surface, when you start acc, the front lifts and the weight is shifted to the rear of a car (giving RWDs an advantage), now imagine a car on an incline, where the car is already rear heavy and then you apply throttle.

A FWD should suffer more in such a situation.

I've taken our Innova on very steep inclines and it did a pretty good job. Infact, when i try reversing on an incline, the wheels spin at the slightest hint of throttle.

Lets asume a regular FWD has a weight distribution of around 60% front and 40% rear on a flat surface, as the front is lifted, the weight will get transfered to the rear reducing traction at the front.

Quote:
Anyone wonder why rear wheel drives are not preferred in snow, especially if you have slopes?
It need not be a slope, even when you drive a RWD on a slippery flat surface, its very easy for the vehicle to spin out.

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Last edited by Shan2nu : 18th August 2009 at 00:35.
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Old 18th August 2009, 01:06   #17
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My dad had this problem when we were in kashmir.
The road was quite steep and rocky
My dad was hesitant and went up slow with just him alone in, the car got stuck and cudnt go ahead, then some dudes came with their gypsy and helped us out, they told us that the best way was to not slow down and also have people siting in the car as it would increase traction.
1 more thing, the wagon r has more power than the omni could also contribute.
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Old 18th August 2009, 01:39   #18
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Quote:
1 more thing, the wagon r has more power than the omni could also contribute.
The Omni couldn't climb due to wheel spin. So lack of power wasn't the prob.

It mostly happens due to the excess amount of power being delivered to the driving wheels.

Heres a vid showing how controlled power delivery can make some of the toughest inclines seem like a walk in the park (thanks to traction control).

PS : The traction control part starts at 4:36



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Last edited by Shan2nu : 18th August 2009 at 01:43.
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Old 18th August 2009, 02:05   #19
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Quote:
Originally Posted by GTO View Post
Not only tricky slopes, I remember FWD having a distinct advantage over RWD when first starting the car (Boston). In fact, a couple of RWD car owners used to load their trunks with sandbags for better traction.
There was this lady in the neighbourhood with an E class. The house was on a hilly area and the driveway was a steep up-slope. In the winter the Benz was parked on the street coz it could'nt make it up to the garage.
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Old 18th August 2009, 06:59   #20
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I was surprised to read this thread, because I always had trouble taking an Esteem up steep slopes even on tarmac with 4 people on board. There was enough weight transferred to the rear for the front to get very light and start spinning the wheels. In addition the forward motion itself transfers weight to the rear. I had to ask people to walk up the steep parts to get over this. And a RWD Sierra sailed through, a vehicle with not a high power to weight ratio, and since then my thinking has been RWD for steep climbs - but I guess I could be wrong. Or perhaps, the best solution is a RWD with enough weight over the rear wheels.
Or, a 4x4!!
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Old 18th August 2009, 09:23   #21
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my friend's place in coorg. on top of a steep hill. years ago it was a plain mud road of about 500-600 metres distance which would get terribly muddy , gooey and slushy in the rainy season. steep climb plus mud will be the un-doing of anything short of a serious 4WD.
any guests coming there would need to park their cars on the main road and his dad used to have to ferry them up in jeep loads in his old gypsy 4WD. no other way of them getting to the house.
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Old 18th August 2009, 10:20   #22
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Experts already explained that why it happens and i saw in many hilly places that for climbing tough areas Omnis(due to rear wheel drive) are taken in reverce gear.
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Old 18th August 2009, 10:52   #23
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reminds me of an incident a very long time ago in interiors of kerala.
i was visiting a friend and my car would not climb up the steep path to his house.
so he asked me to reverse in. i was scared for a bit though then, wondering if the car would topple... ha ha
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Old 18th August 2009, 14:56   #24
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Quote:
Originally Posted by Sawyer View Post
I was surprised to read this thread, because I always had trouble taking an Esteem up steep slopes even on tarmac with 4 people on board.
I remember the same problem with my Esteem. Had more to do with the engine's poor low end torque & tall gearing than FWD / RWD. Generous amount of clutch slipping required on steep inclines.
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Old 18th August 2009, 15:39   #25
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Gearing in reverse is normally lower.
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Old 18th August 2009, 16:02   #26
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Having lived in Switzerland and owned a rear wheel drive BMW 320. I can tell you it is terrible to drive in Winter when the roads are covered in ice/snow and you have an incline to go up. Many times I have had to have onlookers push the car up which was embarrassing. Most often I would just leave the car in the garage through the worst of the winter since it wasnt worth the hassle.

My last car on the other hand was a Renault Laguna which was a front wheel drive. That car never had an issue in winter on the same road conditions and I could drive it with confidence right through the worst of the winter.

So I would say that the front wheel drive is making most of the difference in this case as well.
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Old 19th September 2009, 18:55   #27
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I guess people have made it a little bit more complicated then it ought to be!so its my turn i guess to enhance it! LOL

case seems simple : not enough traction(friction between surface/tyre)
1. firstly coff of friction was drastically reduced( loose gravel and mud in scenerio.
2. both the vehicles were made lighter.hence normal reaction reduced for both the cars.
However reduction of normal reaction worked against OMNI and worked for estilo.As driven wheel were made lighter in Omni hence it was left with very little traction.(as such omni has very light rear,one adult can literally lift its one of the rear tyre couple of inches from ground,if someone places a buck bet for it).
For estilo additional weight was making the car rear heavy ,front driven wheels would have had to pull the additional weight ,without it contributing significantly much to normal reaction on front wheels!



weight transfer is there towards rear wheel but its only when the vehicle is accelerating. harded the acceleration more weight transfer,but it really does not make a lot of difference in cars like omni and estilo when they are purposefully climbing( when the driver already knew its going to be a hard climb for the car he obviously woudnt let go off the clutch at 5000 rpm).moreover acceleration figures of indian cars are hardly enough to make significant contribution to weight transfer.

someone noted the difference in reverse gearing being lower than forward first gear.nice find! However another thing worth noting is,Omni has final reduction of about 4.2,where as estilo has final reduction of 3.8. so lack of power is taken out of question as a Omni would be sending almost equal torque to wheels if not more than estilo despite being 38 BHP.Thats why it has good load carrying capicity but compromised top speed!


It would have been much better if the Omni driver had ratained two or three people in the back seat.(engine in Omni isnt Mid mounted,its literally sitting right over the front wheel plane)
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Old 20th September 2009, 15:48   #28
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If you ask me its the suspension.

The WagonR has a full Independent Front setup with enough torque. The omni has a Leaf sprung suspension with live axle. In case of WagonR when torque is applies the wheel still maintains contact patch for a long duration than the Omni which has more suspended to unsuspended weight ration.

As a standard the contact patch duration is a ratio of suspended weight(weight of all the components comprising the suspension system) and the weight on the suspension system. This is the reason a Bus has far better traction than a light car, with more contact patch to weight ratio.
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Old 20th September 2009, 16:33   #29
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Quote:
Originally Posted by kuttapan View Post
Omni is what ? 38 bhp? Wagon R - 60 odd bhp? That itself is a huge difference.
The torque figures are higher too!

Maybe the same driver should try doing the incline in both vehicles!
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Old 13th April 2015, 20:09   #30
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Default Re: FWD climbed a hill but RWD failed. Reason ?

I stumbled upon this thread and thought I must share my experience. We regularly drive upto our home in the himalayas in a variety of cars, ranging from a Swift D, Honda City (both dolphin shape and ANHC), and an i10 (all FWD cars). The last km or so is a constant 1 in 10 slope, with some loose gravel, but we never had an issue with wheelspin, in any of the cars mentioned above.
A couple of months ago, we had borrowed a friends Innova, which suffered from lots of wheelspin, we finally did make it up, but it was quite a nightmare. To give the innova the benefit of doubt, it is possible that we were not familiar with its dynamics and handling and thus this happened, but it did leave us wondering :O
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