First real experience with AWD in floodng conditions..

[ejb3232]

I've had my car since january and although its been in the rain, I have never had to drive in this kind of downpour before. (Im in pa so we have been dealing with rain for 6 straight days now). Was on the turnpike this morning where it was pretty much flooded. Legacy felt great and stayed nice and straight. Hit 2 badly flooded pockets in the road that I didnt see at about 50 mph and the car cut right through it, no signs of hydroplaning at all. This is my first subaru and now realize why subaru owners love their vehicles so much. Obviously great in the snow, but just as great in the rain which I dont think a lot of people realize about the continous all wheel drive system. I knew it would be good in the snow, but never this good in the rain!

[rallispec]

we've been getting the same rain around here -and the legacy is noticeably better in it than my old FWD nissan - however I still have noticed that i've hydroplaned several times.. (more a problem of the tires than the car though) - but it always carryies straight through the puddles and keeps control.

[jond_68]

You have advans on the 2.5i right? Re92s aint so good in water.

 

I agree. I did ok in the water, however I detoured when I saw the 12 inches or so of water rushing over the road directly in front of me. No sense damaging the car(or myself).

[ejb3232]

yep. have advans. alhtough when the time comes Ill probably get some Contiextremes.

[Garandman]

Physical laws are pretty strict, so going fast enough and with deep enough water eventually you are going to hydroplane....

[robinlsb]

Physical laws are pretty strict, so going fast enough and with deep enough water eventually you are going to hydroplane....

 

When the water is deeper than the tread, you WILL Aquaplane at some point.

[Xenonk]

driving in the autocross with the AWD is soo much fun, even with just 3/32" worth of tread on the Azenis. i still managed to get a fast time comparably speaking and the car is so predicable... even with stiffer suspension and running on semi bald tires for what most of you will think (because it's at the wear bar) the car is still controllable and i havent had a problem with the hydroplaning even with the crazy rain this weekend out in the wet. The car rotates nicely and it's certainly all under control. I have driven back in a monsoon from South Carolina in a down-pour and a half, the GT runs well, even at 70+ mph on I-95. i felt no hydroplaining, even on Azenis RT-615 tires with 4/32" tread left. Proper alignment with proper tire pressures goes a long way.

 

I think the best part is that I still managed a 2.0 and 2.1 60' times at the prosolo in an AWD car while the rest of the field dropped down from a 2.2 to a 3.0s for the reaction time.. clearly you can see the AWD advantage in the launch.

 

But the one thing I would like to note is with such rain, I drop the tire pressures way lower to go faster in the wet.. for autocrossing it's ok, but for street, no one should go as low as an autocross wet setup. The car will certainly feel more stable with some lower tire pressures when the wet stuff hits the ground.

[robinlsb]

driving in the autocross with the AWD is soo much fun, even with just 3/32" worth of tread on the Azenis. i still managed to get a fast time comparably speaking and the car is so predicable... even with stiffer suspension and running on semi bald tires for what most of you will think (because it's at the wear bar) the car is still controllable and i havent had a problem with the hydroplaning even with the crazy rain this weekend out in the wet. The car rotates nicely and it's certainly all under control. I have driven back in a monsoon from South Carolina in a down-pour and a half, the GT runs well, even at 70+ mph on I-95. i felt no hydroplaining, even on Azenis RT-615 tires with 4/32" tread left. Proper alignment with proper tire pressures goes a long way.

 

I think the best part is that I still managed a 2.0 and 2.1 60' times at the prosolo in an AWD car while the rest of the field dropped down from a 2.2 to a 3.0s for the reaction time.. clearly you can see the AWD advantage in the launch.

 

But the one thing I would like to note is with such rain, I drop the tire pressures way lower to go faster in the wet.. for autocrossing it's ok, but for street, no one should go as low as an autocross wet setup. The car will certainly feel more stable with some lower tire pressures when the wet stuff hits the ground.

 

I loved racing in the rain, it separates the "men" from the boys. Running in the rain requires a soft touch and a lot of clit, clearly Xenonk has that skill.

[ejb3232]

Dont get me wrong, Im not going to do 90 in the rain just because I have AWD. Just wanted to note a sense of satisfaction in making the decision to buy a subaru. Coming from a grand am, I feel 100 times safer in my legacy in any weather condition.

[Xenonk]

I loved racing in the rain, it separates the "men" from the boys. Running in the rain requires a soft touch and a lot of clit, clearly Xenonk has that skill.

 

 

cory ridgick in his STS Impreza 2.5RS kicked my butt hard this weekend of running nearly a full second faster than me.. and I was running a full second from everyone else in the rain in my class.. it's tough going against him.. of course it is, he's been winning prosolos recently and is a national level driver! If anyone got the skills, it's him, not me.

[Xenonk]

Dont get me wrong, Im not going to do 90 in the rain just because I have AWD. Just wanted to note a sense of satisfaction in making the decision to buy a subaru. Coming from a grand am, I feel 100 times safer in my legacy in any weather condition.

 

 

totally acceptable, i am just making a note that the car, with a proper alignment and good tires can really make a difference. I posted up some videos of me at CMP (Carolina Motorsports Park last month) of Saturday in the dry with r-compounds vs. Sunday's downpour in the rain with Street tires.. and you can see the difference.

 

Here are the links:

Dry with Kumho V700 (R-compounds)

http://media.putfile.com/CMP-Kumho-V700-Dry-Lap

 

Dry with Falkens Azenis (Street Tires)

http://media.putfile.com/CMP-Falken-Azenis-Dry-Lap

 

Wet with Falkens Azenis (Lap1)

http://media.putfile.com/CMP-Falken-Azenis-Wet-Lap1

 

Wet with Falkens Azenis (Lap2)

http://media.putfile.com/CMP-Falken-Azenis-Wet-Lap2

 

Wet with Falkens Azenis (Lap3)

http://media.putfile.com/CMP-Falken-Azenis-Wet-Lap3

[SBT]

Keefe - would respectfully disagree on lowering the tire pressures for high-speed wet driving on the freeway/roadways. It may be perfectly acceptable for auto-x but believe me, you'll be much more prone to hydroplaning with lowered tire pressures than you will with pressures set at/slightly above stock. Check out this link. http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=3

 

SBT

[Xenonk]

Keefe - would respectfully disagree on lowering the tire pressures for high-speed wet driving on the freeway/roadways. It may be perfectly acceptable for auto-x but believe me, you'll be much more prone to hydroplaning with lowered tire pressures than you will with pressures set at/slightly above stock. Check out this link. http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=3

 

SBT

 

 

from my experience and the rest, lowering the tire pressure to soften the tire can be seen two ways:

 

1) increase contact patch that may cause a higher chance of hydroplaning

2) softening the last part of the suspension (tires) to cushion the blow from hitting the water.. too stiff is not good when you are slapping against the water, you want to gently cut into the water, not press down on it a full force.

 

Tirerack has some great info, I wont doubt that, but trying to drive on higher inflated tires where the shoulders starts to round off is asking for hydroplaning to occur more so than a flatter tire.

[robinlsb]

from my experience and the rest, lowering the tire pressure to soften the tire can be seen two ways:

 

1) increase contact patch that may cause a higher chance of hydroplaning

2) softening the last part of the suspension (tires) to cushion the blow from hitting the water.. too stiff is not good when you are slapping against the water, you want to gently cut into the water, not press down on it a full force.

 

Tirerack has some great info, I wont doubt that, but trying to drive on higher inflated tires where the shoulders starts to round off is asking for hydroplaning to occur more so than a flatter tire.

 

I agree with Xenock here. And lap times in the past have proved it. I think it is more a tread on the road issue. The G forces in the rain are less, so lower tire pressure allows for more contact patch IMHO.It has been my experience that you run the lowest tire pressure possible while maintaining the same temperature across the tread.And in the rain,we always lowered TP.

[tantal]

Dont get me wrong, Im not going to do 90 in the rain just because I have AWD. Just wanted to note a sense of satisfaction in making the decision to buy a subaru. Coming from a grand am, I feel 100 times safer in my legacy in any weather condition.

 

You should realize though that ~ 80 % of the feeling you have comparing wet to dry going from car to car is due to the tires. Particularly if you feel a more stable ride, at speeds less than say 70 mph where aero effects can really make a difference in feel, you are only feeling how good your tires are.

 

You'd be amazed at what a real summer HP tire feels like in the rain - some are great and some awful, but I like a good rain tire because almost any good tire is more than fine in dry conditions.

 

The big advantage of the subaru drive train is during cornering. Definately a huge improvement in keeping the power down compared to either fwd or rwd. Also a good, balanced weight distribution is key here - another subaru advantage, particularly in the wagon, but of course it is not the 50/50 of a bmw.

[Sk8erOrd]

As an addendum to the cornering advantage comment, it's also very beneficial in less than ideal conditions (wet, snow, etc) when you have to make quick manuevers to avoid running into things like debris in the road, another car who swerves, whatever.

[Garandman]

from my experience and the rest, lowering the tire pressure to soften the tire can be seen two ways:

 

1) increase contact patch that may cause a higher chance of hydroplaning

2) softening the last part of the suspension (tires) to cushion the blow from hitting the water.. too stiff is not good when you are slapping against the water, you want to gently cut into the water, not press down on it a full force.

 

Tirerack has some great info, I wont doubt that, but trying to drive on higher inflated tires where the shoulders starts to round off is asking for hydroplaning to occur more so than a flatter tire.

 

The model developed by NASA shows better hydroplaning resistance with higher pressure.

There are other types of hydroplaning driven by other variables, such as the road surface material, shape of surface, etc. Presumably the tread groove width and depth would impact it as well.

[SWP-LegacyGT]

RE92's in heavy rain here in Oregon = Signing your own death certificate.

[TSiWRX]

Question -

 

Please pardon my ignorance on this issue, and help enlighten me.

 

I was under the impression that our Boxer engines sat pretty low, compared to most other "average" vehicles of our genre.

 

Would this impact our LGTs' ability to plow through more heavily submerged roadways?

 

Our intakes are situated decently high...but what about the block?

 

Thanks in advance for any advice/knowledge!

[planigan]

Question -

 

Please pardon my ignorance on this issue, and help enlighten me.

 

I was under the impression that our Boxer engines sat pretty low, compared to most other "average" vehicles of our genre.

 

Would this impact our LGTs' ability to plow through more heavily submerged roadways?

 

Our intakes are situated decently high...but what about the block?

 

Thanks in advance for any advice/knowledge!

 

Well, check out this thread...

 

For what it's worth I myself had a little bit of a scary moment last week... although nowhere near as bad as that guy. I was driving home one night through a storm here in Michigan, and there was tons of standing water everywhere on the roadways. Up to a couple of inches in some places, and since visibility was so low they would just sneak up on you. Even doing 25 MPH and hitting one was a bit disconcerting because of the sudden deceleration. Anyway, the worst was at an underpass that dipped into a slight valley. I'm not sure exactly how high the water was -- maybe 5 - 6 inches -- it was hard to tell since cars going through next to me and in front of me had stirred up waves (yes, waves).

 

Luckily, I saw it just before plowing into it. It did catch me by surprise though, and I ended up slipping the clutch after downshifting to get through it. There was definitely an odd burny smell after crossing through, but it didn't smell exactly like clutch. The smell did subside, and the car seems to be running fine now.

[robinlsb]

The model developed by NASA shows better hydroplaning resistance with higher pressure.

There are other types of hydroplaning driven by other variables, such as the road surface material, shape of surface, etc. Presumably the tread groove width and depth would impact .

 

I agree ,in a straight line, that this is true. However, once corners are involved things are not the same.

[LIZARD]

. There was definitely an odd burny smell after crossing through, but it didn't smell exactly like clutch. The smell did subside, and the car seems to be running fine now.

 

Water on the "hot exhaust parts". Happens at the carwash too.

[TSiWRX]

Well, check out this thread...

 

WOW!!!!

 

Thanks for that pointer!

[Garandman]

The model developed by NASA shows better hydroplaning resistance with higher pressure.

There are other types of hydroplaning driven by other variables, such as the road surface material, shape of surface, etc. Presumably the tread groove width and depth would impact .

 

I agree ,in a straight line, that this is true. However, once corners are involved things are not the same.

 

So what is the difference and who has researched it? I'd think the traction circle applies to the other hydroplaning modes just the same.

[planigan]

Water on the "hot exhaust parts". Happens at the carwash too.

 

Oh good, that just happens to be what I told myself to keep from freaking out -- thanks for confirming