Understeer comparison with other cars
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Understeer comparison with other cars
Alright I dd a quick search but didn't come up with much, so here's my thoughts and questions:
I've been watching those random videos motorweek, and that british guy who's always excited to drive......
Now it's a known fact that most AWD cars have a natural tendency to understeer... so the questions springs up when looking at the sti and comparing it to the evo and porsche 911 awd.
Now the Evo I heard has a lot less understeer than the Sti, and I was wondering what causes this... whether it be the balance of the car or other suspension setup or different awd system?
and also I know the Porsche is way up there, but what makes it this car so damn grip-happy? is it the weight and how its balanced? or is it the different awd system it has?
I know that was a mouthful but thanks for any help.
I've been watching those random videos motorweek, and that british guy who's always excited to drive......
Now it's a known fact that most AWD cars have a natural tendency to understeer... so the questions springs up when looking at the sti and comparing it to the evo and porsche 911 awd.
Now the Evo I heard has a lot less understeer than the Sti, and I was wondering what causes this... whether it be the balance of the car or other suspension setup or different awd system?
and also I know the Porsche is way up there, but what makes it this car so damn grip-happy? is it the weight and how its balanced? or is it the different awd system it has?
I know that was a mouthful but thanks for any help.
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IMHO, I think Subaru engineers tune our suspensions this way so the majority of the people driving Subaru's can safely drive the cars at speed and not have to worry about the car swapping ends suddenly. The EVO always seems to be favored by performance car magazines because the fact that the car is tuned much more "sharply" from the factory. It's no wonder so many WRX owners who enjoy their cars to exhibit more rotation under hard cornering are so pleased when they get a stiffer rear sway bar. Some people argue that our cars should come this way from the factory.
For most drivers (myself included) will find the stock suspension quite easy to handle at the limit. The stock suspension will naturally understeer, but if provoked the car will oversteer, but the car has an incredible ability to straighten itself out instead of letting the car swap ends. I'm comfortable with how the car handles, but I'm excited now to get an upgraded RSB to make the car more neutral, without upsetting the forgiving nature of the car too much.
For most drivers (myself included) will find the stock suspension quite easy to handle at the limit. The stock suspension will naturally understeer, but if provoked the car will oversteer, but the car has an incredible ability to straighten itself out instead of letting the car swap ends. I'm comfortable with how the car handles, but I'm excited now to get an upgraded RSB to make the car more neutral, without upsetting the forgiving nature of the car too much.
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the AWD Porsches benefit from having a rear mounted engine. rear engine cars are prone to really pronounced oversteer, and that helps balance out the tendencies of AWD understeer. watch a rear/rear car like an MR2 sometime, and you'll see what i'm talking about. combine that with some seriously large contact patches, and the more advanced traction control/diffs/etc and that pretty much does it.
as to why the evo has less understeer, its down to engineering and car setup. i personally don't know of enough differances to explain exactly what causes the differance.
as to why the evo has less understeer, its down to engineering and car setup. i personally don't know of enough differances to explain exactly what causes the differance.
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one very important factor is weight distribution. in most awd layouts (production at least) the engine is mounted at one end of the car, not in between the two axles. this has to do with driving both diffs off of the back of the engine without having to use a jackshaft. buy using a longitudinally mounted engine, subaru has a lot of weight hanging relatively far in front of the front axle leading to a nose heavy weight distribution. porsche is exactly opposite of this, they have a really heavy butt which is more acken to oversteer. the mitsubishi has a transversly mounted engine so the weight is as close to the front axle a possible, therefore their weight distribution is closer to 50/50. if you think your subaru has a lot of understeer, you should try driving an audi, my 90Q20v has horrendous understeer due to an inline 5 cylinder sitting completely in front of my front axle.
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Originally posted by dropkick_muppet
the AWD Porsches benefit from having a rear mounted engine. rear engine cars are prone to really pronounced oversteer, and that helps balance out the tendencies of AWD understeer. watch a rear/rear car like an MR2 sometime, and you'll see what i'm talking about. combine that with some seriously large contact patches, and the more advanced traction control/diffs/etc and that pretty much does it.
the AWD Porsches benefit from having a rear mounted engine. rear engine cars are prone to really pronounced oversteer, and that helps balance out the tendencies of AWD understeer. watch a rear/rear car like an MR2 sometime, and you'll see what i'm talking about. combine that with some seriously large contact patches, and the more advanced traction control/diffs/etc and that pretty much does it.
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Only people like Tiff Needell can find the oversteer in a Porsche of any kind and live to tell about it (or run and hide from whoever the Porsche belonged to). Under normal circumstances (read: less than 9/10ths driving) any 911 will understeer worse than any WRX. It's the nature of having small tires up front with no weight on them. However, gifted drivers can induce power oversteer and inertial oversteer on a Porsche and not go *** over teakettle into the weeds because they are, well, gifted.
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Originally posted by BAN SUVS
It's the nature of having small tires up front with no weight on them. However, gifted drivers can induce power oversteer and inertial oversteer on a Porsche and not go *** over teakettle into the weeds because they are, well, gifted.
It's the nature of having small tires up front with no weight on them. However, gifted drivers can induce power oversteer and inertial oversteer on a Porsche and not go *** over teakettle into the weeds because they are, well, gifted.
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I was discussing this with my friend before too... and he was telling me about how different companies have their own version of awd systems...
he told me that nissan skyline had the best awd system ..... i was kinda skeptical but is that true?
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the Skyline has a very advanced AWD system, and its quite good. i don't know if i'd say its the best, but to find a better system you're looking at much more expensive cars like Porsches, Lambos, etc.
larger, and by larger i mean wider, and having a larger contact patch won't create onversteer on their own. cars like the 911 have much larger rear tires than fronts. if you were to put wider front tires on a EVO or WRX, you'd find that the car would understeer less, simply because it has more front grip. some auto-x'ers with lots of $$$ to throw at their suspension will run the same size tires front and rear, but with wider front rims i.e. 17x9 in front, and 17x8.5 in the rear resulting in a larger front contact patch.
larger, and by larger i mean wider, and having a larger contact patch won't create onversteer on their own. cars like the 911 have much larger rear tires than fronts. if you were to put wider front tires on a EVO or WRX, you'd find that the car would understeer less, simply because it has more front grip. some auto-x'ers with lots of $$$ to throw at their suspension will run the same size tires front and rear, but with wider front rims i.e. 17x9 in front, and 17x8.5 in the rear resulting in a larger front contact patch.
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From: north jersey
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hm I guess I'll start looking into the tires/wheels section of this forum... I'm going down through each forums one by one. um but the question still remains about moving parts from the engine bay and moving it to the trunk of the car.... or elsewhere to balance it out. e.g. battery.
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Originally posted by muhon
hm I guess I'll start looking into the tires/wheels section of this forum... I'm going down through each forums one by one. um but the question still remains about moving parts from the engine bay and moving it to the trunk of the car.... or elsewhere to balance it out. e.g. battery.
hm I guess I'll start looking into the tires/wheels section of this forum... I'm going down through each forums one by one. um but the question still remains about moving parts from the engine bay and moving it to the trunk of the car.... or elsewhere to balance it out. e.g. battery.
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Originally posted by muhon
so... bigger tires would also induce oversteer?
-----
I was discussing this with my friend before too... and he was telling me about how different companies have their own version of awd systems...
he told me that nissan skyline had the best awd system ..... i was kinda skeptical but is that true?
so... bigger tires would also induce oversteer?
-----
I was discussing this with my friend before too... and he was telling me about how different companies have their own version of awd systems...
he told me that nissan skyline had the best awd system ..... i was kinda skeptical but is that true?
Yes, different companies have different all wheel drive systems. The one in the Skyline is exremely robust, capable of handling well over 1000 horsepower. The system is also very sophisticated as far as torque transfer to maximize traction and acceleration on the track.
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