Hi there, the UK has had a surprising amount of snow this winter. We have a 2003 6cylinder Legacy Outback Auto and a 2.5XT manual Forester. In soft snow the grip of the Legacy is excellent but if pushed goes as I would expect into an understeer type "run wide" slide on its Yokahomas. The XT however despite an apparent equal distribution 4x4 system seems much more ready to hang out its tail in a more RWD type way (again on OS Yoks). Is this how it is set up? In wet and dry weather it handles very neutrally so I was surprised. Any comments from those more expert on snow driving would be appreciated. gpchris
on road handling in snow
1 - 11 of 11 Posts
The auto Subarus have a different Front/Rear bias then the manual trans cars. I used to have an Outback Limited and I think I read 60/40 for the auto and 50/50 for the manual. I don't know how correct that is in your case for your specific year though.
gpchris-
Having grown up with a RWD series of vehicles, I actually prefer the 'oversteer' tendency. But that is wide of the mark you've inquired of...I have a 2004 FXT with 4EAT...oddly enough, the front rear bias in 3rd and 4th gears is pronounced to the front (80-20 or 90-10) based on the assumption that 1)gas mileage will benefit from FrontWD bias and 2)most users won't need to lay a lot of power to less than ideal conditions at speeds over 60 mph.
That said, one of the things you can do is to alter tire pressures front to rear. SOA recommends not going beyond a 4 psi difference, but this is for pavement...once you're on snow or ice, there is enough slippage that no harm is done from differences in circumference due to air pressure difference...you'd want to be able to return to balance pressure once back on pavement. Bias the front with higher pressure, you introduce more oversteer, bias the rear with higher pressure, you introduce more understeer.
These are relative terms when you have an AWD vehicle, as the AWD is an engineered compromise. The FXT will never, never handle like a rear-engine, rear-wheel drive Porsche. Were the FXT able to have the STi control over front rear bias, the FXT could mimick handling of most American cars of prior century.
Increasing weight distribution from front to rear would have the effect of increasing rear traction and an over-steer handling effect. One thing I've noticed is the tendency of FXT to lift front end on takeoff, which has the effect of reducing front end traction so there will be tradeoffs on changing weight distribution.
-Quick
Having grown up with a RWD series of vehicles, I actually prefer the 'oversteer' tendency. But that is wide of the mark you've inquired of...I have a 2004 FXT with 4EAT...oddly enough, the front rear bias in 3rd and 4th gears is pronounced to the front (80-20 or 90-10) based on the assumption that 1)gas mileage will benefit from FrontWD bias and 2)most users won't need to lay a lot of power to less than ideal conditions at speeds over 60 mph.
That said, one of the things you can do is to alter tire pressures front to rear. SOA recommends not going beyond a 4 psi difference, but this is for pavement...once you're on snow or ice, there is enough slippage that no harm is done from differences in circumference due to air pressure difference...you'd want to be able to return to balance pressure once back on pavement. Bias the front with higher pressure, you introduce more oversteer, bias the rear with higher pressure, you introduce more understeer.
These are relative terms when you have an AWD vehicle, as the AWD is an engineered compromise. The FXT will never, never handle like a rear-engine, rear-wheel drive Porsche. Were the FXT able to have the STi control over front rear bias, the FXT could mimick handling of most American cars of prior century.
Increasing weight distribution from front to rear would have the effect of increasing rear traction and an over-steer handling effect. One thing I've noticed is the tendency of FXT to lift front end on takeoff, which has the effect of reducing front end traction so there will be tradeoffs on changing weight distribution.
-Quick
Also keep in mind the Forester has a shorter wheel base. Which means the time it takes for the rear to trade places with the front is less then it would be in the outback. This may give you the impression the Forester is more eager to step out then the outback as you have less time to correct thus the correction has to be more sever.
Correct me if I'm wrong here. But I believe there is a different philosophy on AWD between manual and automatic Subaru's. I seem to recall reading that manual trannies have viscus fluid that uses gravity and motion to determine what wheels need more power and what ones do not; where as the auto uses some combination of that and computer control.
If the aforementioned is the case, could it not be possible that we are comparing bananas to oranges?
If the aforementioned is the case, could it not be possible that we are comparing bananas to oranges?
We have an Outback and Forester, both 4EAT's. The Outback will understeer in the snow until you really hammer on it, then it will rotate and Oversteer like the Foz. It just takes more effort to make it rotate because it is a longer wheelbase. However, when it swings around, it's much more fun. I can make it hang out around corners much more smoothly than the Forester. :biggrin:
If you are replacing tires, or getting winter tires, you want to go skinnier for snow. 205 instead of 215, etc.
Reading this really makes me miss my Outback and drifting it around corners in the fresh blue powder during a full moon. :woohoo:
I miss my Baja as well! It had the 4EAT and it was better footed in the snow than my manual Forester. It seems when I get in deep snow, the Forester wants to fight me on which direction it wants to go as well as it wants to drift much more than my Baja. With my Baja on good roads, I could take street corners at 40MPH on the stock Potenzas and it wouldn't fishtail, but boy! Did those tires protest! I will not do that in the Fozzie. It just seems too top heavy to try that maneuver...
In short, I favor the AWD auto trans setup ve. the AWD manual setup. Just my $.02.
In short, I favor the AWD auto trans setup ve. the AWD manual setup. Just my $.02.
As far as I remember, the 4EAT has an active center that will change from 55/45 to 90/10 depending on slippage. Where as the 5MT is stuck at 50/50. The shift to a 90/10 for the 4EAT (automatic) will bring out the "understeer" you felt.
I might be wrong, but that is what I know.
I might be wrong, but that is what I know.
1 - 11 of 11 Posts
Join the discussion
Join now to ask and comment!