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2000 RS, silver, blah, blah, b
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Discussion Starter · #1 ·
So I'm talking to one of my Auto-X buddies that happens to own, and be a fanatic of, a mustang. So he doesn't think anything other than a RWD V-8 is worth it. But he realizes that I continually beat him at every event. He rode with me once and he noticed the MASSIVE push with our stock setups. Well, we were talking theory today and I was thinking about super wide rims and drag radials when he joked about skinnies up front. That made me think about the front losing traction... now this is where the question begins.

IF you were to have stock size ooooohhhh lets say, Falkan Azenie Sports up front and 17"x8.5" customs wrapped in Hoosier Drag radials under custom wide fenders.
Would our cars act like a rear wheel drive car due to all the available traction in the rear and then once the rears slip the fronts can pull you away. Right?

I'm not SUPER sure on this but I think it would work. Correct me if I'm wrong... the things you thnk about when you're underway.

Brett
 

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You would not be doing your tranny any favors by going that route. Wouldn't reccomend it.
 

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You want the exact opposite, actually. If you've got understeer, you want to *increase* the front grip and/or *reduce* the rear grip. Put the big ol stickies on the front, and you'll be tail-wagging all day long. If you keep the diameters the same, your center diff will be fine -- the width won't matter.

Sean
www.subrew.com
 

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Discussion Starter · #5 ·
OK lets get rid of the drag radials, and put on some hoosier DOT legal slicks (that are made for road races) and keep the falkans up front. The thing is I don't want to make the car go waggin' I want it to act like a RWD car that will pull me away if I get into problems with the rear end. The thing I'm not TOO sure about is: Will the car bias more power to the rear end due to the fact that under acceleration with weight transfer there will be a HUGE tire patch in the rear? I would like to take advantage of that if it will send more power to the rear with more traction back there. Or am I overestimating the "power of all wheel drive"? I should have explained myself better.

L8r,
Brett
 

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If you put race tires on the rear and street tires on the front, you will push worse that if you have street tires on both ends. Why? Because our front wheels still do some of the driving and our car will still act lie an all wheel drive car. You're better off trying to balance the car with springs and shocks and making fine adjustments to the cars handling with air pressure adjustments.

What kind of suspension setup are you running?

Brian
 

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Discussion Starter · #7 ·
bvondran said:
You're better off trying to balance the car with springs and shocks and making fine adjustments to the cars handling with air pressure adjustments.

What kind of suspension setup are you running?

Brian
Yo, B... ha

I'm doing the same thing that you have said, right now I have a 20mm rear sway bar from a US WRX and the rest is stock... for now:devil: . This is just a follow up on a theoretical discussion I was having with my buddy. I guess I was just overestimating the ability of our AWD.

Brett
 

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If you want tail wagging, the way to do it with tires is by using the crappiest equal diameter tire on the rears that you can get, and put the grippiest tires on the front, again with the same diameter (as not to mess up your diffs)

When in drift mode, I used to Auto-x with Bridgestone 730's in front and stock RE-92's in the rear, both 205/55, 16... Works like a charm :) One of the easiest ways to get power on oversteer in NA impreza's...
 

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Dude, I'm not sure you're understanding what people are trying to say. Your car 'pushes' (proper term is 'understeer') because the back tires have more grip than the front.

To make the car not 'push' (understeer) as much, (IE make it handle more like a Mustang, which oversteers) you'll want to increase grip to the front tires.


Here's what you should do: (stolen from www.ravensblade-impreza.com)

To Reduce Understeer or Increase Oversteer


Front tires:
Increase tire pressure in 2.5psi increments
Increase Section Width
Lower the Aspect Ratio
Reduce front tread depth

Rear Tires:
Reduce tire pressure in 2.5psi increments
Reduce section width
Install higher aspect ratio tires
Increase rear tread depth

Front Wheels:
Install wider wheels
Install lighter wheels

Rear Wheels:
Install narrower wheels
Install heavier wheels

Front Alignment settings:
Dial in more negative camber
Dial in More toe-out
Dial in more positive caster

Rear Alignment settings:
Dial in more positive camber
Dial in more toe-out (Same as front)

Anti-Sway bars:
Soften the Front
Stiffen the Rear

Springs & shocks: s:
Soften the Front
Stiffen the Rear


Weight Distribution
Reduce front weight
Increase rear weight

Aerodynamics:
Increase Front Downforce
Reduce rear downforce


-scott-
 

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Rear Alignment settings:
Dial in more positive camber
all of that stuff is right, but i think this should read have less negative camber. although i guess if just sliding the car and not actually going fast were your goals, + camber would work.
 

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less negative = more positive.

Most tuners recommend -0.5 to 0.0 degrees negative camber for street cars. You'll need special oblong camber-adjustment bolts to do this, stock doesn't let you adjust rear camber (or at least, not to these specs).




NavyRS-T, personally I'd recommend you adjust your camber settings, more negative camber up front (stock max. is around 1 degree negative I think), and less negative camber in the rear, as little as possible. Try to get rear camber to 0 degrees. Then make the front tire pressures about 4psi less than the rear tires, and your car wil oversteer a lot more than before. All these things are very cheap to do. If you still need more oversteer, look into swaybars and endlinks. Then get an Anti-Lift Kit from whiteline, that should help you a lot.

-s-
 

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NavyRS-T If you want the AWD RS to handle like a RWD V-8 you'll need more rearward bias in the center diff. RWD V-8s have "power-on" oversteer b/c they have the power to break loose the rear wheels more or less at whim. The RS can drift, have "drop-throttle" oversteer but without changing the bias on the center diff (locked mind you) you probably will never be able to get true power-on oversteer. Do dial out the understeer follow the ravensblade path, sticky tires up front will help but suspension tuning is where its at. Another thing to remember, you want to drive smooth to be fast. Drifting is rarely the fast way around the course.
 

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Discussion Starter · #14 ·
Boy, you got the idea, thanks for the info. I really want a really well tuned RWD racecar, maybe a real M3 lightweight:devil::drool: ehh.. dreams. I'm currently tuning, well... saving to make the car handle as best it can. I'm going to get some good all weather tires on some "show-ey" rims and stick some DOT legal race tires on the stockers. I'm hoping to get some DMS 40 golds, and various whiteline suspension components. That will come in time, unless I find something at the same quality and performance (or better) for the same price (or cheaper). Until then I will just read/ study/ ask questions about all the different setups, and learn from peoples mistakes and good fortunes. I was just throwing out the idea because I had remembered (at least I think) that the JGTC Cusco Impreza was/is RWD. Can't be much better than the race car, can you?

L8r,
Brett
 

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Discussion Starter · #15 ·
Boy, you got the idea, thanks for the info. I really want a really well tuned RWD racecar, maybe a real M3 lightweight:devil::drool: ehh.. dreams. I'm currently tuning, well... saving to make the car handle as best it can. I'm going to get some good all weather tires on some "show-ey" rims and stick some DOT legal race tires on the stockers. I'm hoping to get some DMS 40 golds, and various whiteline suspension components. That will come in time, unless I find something at the same quality and performance (or better) for the same price (or cheaper). Until then I will just read/ study/ ask questions about all the different setups, and learn from peoples mistakes and good fortunes. I was just throwing out the idea because I had remembered (at least I think) that the JGTC Cusco Impreza was/is RWD. Can't be much better than the race car, can you?

L8r,
Brett
 

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Remember, adjustable center diffs can be had... for a price. Also, Cobb and a few others have successfully converted scoobies to RWD.
 

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that the JGTC Cusco Impreza was/is RWD. Can't be much better than the race car, can you?
they don't have a choice. rules state that all cars in that series must be RWD. I'm sure that they would love to use the AWD (remember F1 in those days :eek: ) but they are regulated. so in short, yes, you can be better then a race car. quite easily if you have the same budget and no rules to adhere to ;)
 

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Actually, F1 didn't experiment with awd/4wd much. Ferguson introduced a 4wd drive F1 car (early 60's,) but never campaigned it. By that time, the 3.0-liter, and then 1.5-liter formula required cars to be extrmely lighweight to be competitive, and if memory serves me, by the 1.5-liter days only two drive wheels could be used. this is still the case in current f1 rules.

Ferguson four-wheel drive is really the grand daddy of all our awd system, and was introduced it in the Jensen FF (Ferguson Four) which was a big chysler powered four seat gt car in the 60s. We first saw the FF system in the big pork pie AMC Wagons.

They experimented at Indy with 4wd a bunch though. Just about everybody in the late 60s played with 4wd, including Lotus, Eagle, March, Lola etc. 4wd cars won there a couple years.

Miller ran front-wheel drive cars at Indy – and won several times – back in the 20s and 30s.

But i'm rambling now...

Chris H.
www.subrew.com
 
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