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Ok I always get in this screaming match with a kid I know who has a Mustang. He's telling me his car can outhandle mine because it's RWD and it has a bigger wheelbase etc. In the twistees will a mustang be able to outhandle the WRX? Give me some facts so I can throw this back in his face. Thanks.
 

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if im not mistaken the mustang has a rear solid axle right? where the wrx has independet suspension on all four corners. second we have all wheel drive which may not help at all going into the corner but powering out of corners wow i love awd:D. second i believe our car is lighter.
 

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Well RWD is great, under the right hands. The distribution of weight on the Stang is something in the range of 65/35-front/rear if I'm not mistaken and thus makes oversteer very easy, too easy. Most drivers do not know how to control vast oversteer. Long wheelbase is not good for turning sharp corners...anyone telling you different needs a frontal lobotomy and kept in isolation...j/k. However, with RWD, if one can control power oversteer(with throttle) the offset of longer wheelbase is lessened. Long wheelbase is great for straightline stability, but I'd rather have a wide track to greaten my stability than a long wheelbase. It's all about the area covered by the car in between tyres plus the tyres themselves and the tracks of front and rear. Back to the issue of longwheelbase and RWD, the BMW CSL and GTR cars have 107"wheelbase with wider front track than rear and are RWD. The IS300 has 5" more wheelbase than the Supra(I still don't know what to think about this fact...possibly due to rear passenger orientation). AWD affords mistakes like no RWD can have. As for the stang, I say bring it on, regardless of whether it's base/GT or Bullitt..."in the twisties, your soul is mine!"
 

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one very big thing in suspension design is the axis of your wheel where it makes an arc and where that roll center is compared to the CG. if your cg is higher then your rolling center then your car will want to trip over your wheels more which isnt good. you want your roll center to be above your cg when you acomplish this your car is going to want to lean into turns rather then lean out of turns like body roll but this is really difficult to do because your suspension will be at a wierd angle and when your suspension compresses it will want to move the wheels outowrd making them rubb on the pavement in a horizantal motion that will destroy the tires and will cause you to lose power. its hard to explain in words you need pictures which is hard to do on this forum. maybe some other engineers can explain it better. i guess this really doesnt answer anything and i am just babelling. sorry.
 

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T1, you've made a good point...so no worries about babbling like a baffoon. I'm not a mech engineer myself but I studied lots of physics in college and my mech eng friends would agree. But to simplify the whole discussion, I think I can speak for some(if not a majority) in saying a Stang will not be able to hang with a WRX in twisties under the hands of a less than substantial performance. At the same time, I'd like to say, it was never made for that either...American culture of dragging straights. When talking cars, North Americans want to know what ET you got, in Europe, how fast you hit your fav country curves in the south of France is more important.
 

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Mechanical Engineer to the rescue

Oooh, a suspension argument. KnightWRXRider, your friend is a moron.

1) A shorter wheel base yields quicker, more responsive handling. A longer wheel base, more stable handling.

WRX wheel base = 99.4 in
Mustang wheel base = 101.3 in

2) The WRX weighs 3100 lbs, the Mustang GT coupe 3290 lbs. Lighter is always better.

3) The Mustang is lower and has wider tires. Great for a racetrack with smooth arcing corners, but in the real world the long suspension travel of the WRX allows for better recovery from mid-turn upsets (like gravel, pot holes, branch, animals :D )

4) The WRX has fully independent suspension, as mentioned by T1.

5) AWD, faster corner entrances and exits because the car can both push and pull itself through the turn with out fear of loosing the back end. The coveted "four wheel drift" principle.

Terrible, you got off to a promising start there with your cg and roll center talk. I was about to be impressed when I realized it was one REALLY long sentence and got lost.

The roll center of a vehicle must be lower than the cg of the vehicle, but if it is to low, you will get tire scrub, which greatly reduces cornering speeds.

I didn't realize how much of this stuff I actually knew until I tried to answer these questions. Unfortunately, I don't know how to raise or lower a car's roll center and how the front and rear roll centers should compare for certain handling effects. This, I have to learn.

One more thing. Don't get in screaming matches. My dad always says, "Don't argue with a jackass because after while you can't tell which one is the jackass anymore."

-Jim
 

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well you cant. roll center can only be changed at the manufcautre before the car is built. lets say you have double wishbone suspension like f1 cars. to calculate the center roll you take the angles of the two a arms and draw thier lines through an axis until they intersect where these two lines intersect is the roll center height. does that make sense. are you sure that the roll center most be lower then the cg? i was always told the opposite i will go find out tomorrow.
 

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Platinum...my who is a moron? I started off by saying that long wheelbases are not good for sharp corners. In that, I did not go into specifics(sorry) but what I meant was that long wheelbase will be slower and much less responsive than shorter wheelbases. Furthermore I said that with RWD you can offset(somewhat) a slightly longer wheelbase(=slow steer) with power oversteer to get the car to turn. I never said that short wheelbase is bad, wheelbase length is one of the first things I look for in a new car(which is why I was somewhat skeptical about the new EVO VII over the VI as it's longer). My argument was not to say WRX won't win, because I know it should. My argument as that there are ways to compensate a little for the long wheelbase. In twisties, Stang can't hang with a Rex, as I said before. IF you are going to bad mouth me, please read my post more carefully first.
 

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i was wrong the roll center should be lower then the cg. if you have the roll center at the same height as the cg then there is no body roll, and even though we try so hard to get rid of body roll we still want some. the closer the roll center to the cg the stiffer the car will feel. then theres all this stuff about the forces of the tires and the verticle lift forces when taking turns. thats why you see many hondas with there rear wheel off the ground when they turn is because there roll center is to high and the jacking force(verticle force is a lot higher) causing it to lift.

what amazes me so much is f1 cars. i am a f1 car fanatic. there suspension design is amazing they use a double a arm suspension set up but they dont use any tie rod ends to pivot on instead they just connect the arms directly to the frame with titanium and the titanium acts as there pivoting point which will bend back and forth and they use push rod, and rockers with a torsinal spring so there suspension travel is basically 0. i would assume they would replace the a arms after every race.

amazing
 

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schischwein, my bad, I was referring to KnightWRXRider's "friend" Actually he said "kid" with a mustang. I copied your name by mistake. Your post had nothing to do with comments. I edited my post with the proper name.

My apologies.

-Jim
 

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hey guys a little off topic but why is "rockers" underlined and made into a link in my above response. i know i didnt do that so anybody know how it got there. it links to a furniture store. whats up with that?
 

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TerribleOne: I think it's the new Internet Explorer that's doing it. It's really weird and messed up at the same time because I used to be the webmaster for www.amclendinggroup.com (a mortgage website) and after installing the new IE it automatically underlines and highlights some of the keywords, and when people click on it it links to another company. If you have time start a post in the off topic forum and see if anyone knows exactly waht's going on.

Tim
 

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Platinum, thanks. I appreciate your thoughts, ideas about cars and this forum for all the useful resources. Even when things get rowdy in here, it's never overboard like some forums. Keep up the good work.
 

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Something that appears to have been missed by everyone... (unless I got totally confused by all the engineering talk... in that case disregard my post entirely) is that the Sube´s engine being a boxer has a lower center of gravity than other engines... in this case a v8 or v6 or whatever. This is one of the great things in the WRC... they have less trouble keeping the car´s center of gravity close to the ground = more extrme maneuvering without the engine´s weight eventually affecting your turns for the worse. Something like that. All the ME boys can maybe put this a little more eloquently...
My 0.2$
 

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anybody actually know the height of cg and the height of the roll center?

and is our wieght distribution 50/50 front and back and 50/50 left to right?
 

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Front/Back is 54/46 I believe. I have no idea about right/left though, but I suspect the driver side might be heavier, steering column and such. However, I don't think there is a large difference if it's not already balanced....do you drive with a co-driver when you are pushing it? Driving solo will upset the balance more than anything in the car IMO.
 
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