Try to make my own RUNAWAY IN STOCKHOLM video but when attacking a medium corner, the front tire start making noise.....The front tires size is 245x40x17ZR and the rear is 255...The KONI absorbers were working great, glued to earth but the understeering tear down the fun...actually the speed was not very fast...but already understeerSince the front wheel's camber can't be adjusted, what options do I have ?Want to see my terrible in car video -> 5 MB WMV Format ( Save TArget As )
The cause of understeer ?
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kevster30
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Bro,
Try reducing the tyre pressure of your front wheels to get more grip. Also try increasing the rear pressure. What you are experiencing is too much rear grip due to your offset wheel choice.
Good Luck! BTW, the video isn't too bad.....A+ for effort!
Try reducing the tyre pressure of your front wheels to get more grip. Also try increasing the rear pressure. What you are experiencing is too much rear grip due to your offset wheel choice.
Good Luck! BTW, the video isn't too bad.....A+ for effort!
bimmerman
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Kev, shoudn't it be the other way around? He's getting understeer so not enough grip in front and too much grip at the back so shoudn't it be 1. increase tyre pressure in front and 2. reduce tyre pressure at the back. Correct ah? :dunno:
ALBundy
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Bimmerman, Kevster is correct.
Basically you want the front end to have more grip to induce the car to have more steering and hence oversteer as well. Another way is to have a thicker rear anti roll bar, or a harder suspension set up (rear springs).
Al
Basically you want the front end to have more grip to induce the car to have more steering and hence oversteer as well. Another way is to have a thicker rear anti roll bar, or a harder suspension set up (rear springs).
Al
Lee36328
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With due respect and apologies to above sifus....
bimmerman is correct.
understeer is caused by insufficient grip in front (to simplify a bit).
increasing front tyre pressure would send more weight to the front, thereby increasing the front grip.
fabian is also correct, in that stiffer rear ARB would also reduce oversteer...
bimmerman is correct.
understeer is caused by insufficient grip in front (to simplify a bit).
increasing front tyre pressure would send more weight to the front, thereby increasing the front grip.
fabian is also correct, in that stiffer rear ARB would also reduce oversteer...
fabianyee
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u can try asking Pentagon to see whether they are bringing the Whiteline ARB for E34....
I know for sure they make for E30, E36 and E46...
or check out www.whiteline.com.au
bimmerman
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When I was driving a front wheel drive car it was nothing but understeer, understeer and terminal understeer. So to have some weekend fun I would pump my front tyres about 5 psi higher than my rear tyres and I was sideways! Instead of getting wayward oversteer it was more like a 4 wheel drift with slight oversteer on demand by lifting off the throttle mid corner and once the tail was out and about, I could immediately power on again to get a 4 wheel drift. Serious fun on a FWD!!!
Front 34psi
Rear 29psi
But when it comes to suspension, the reverse is true. Stiffer springs or antiroll bar in front will induce understeer. Stiffer springs or antiroll bar at the rear will give you oversteer.
You can also confirm this on your PS2 Gran Tourismo car settings
ALBundy
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Adoi, with all due respect, LEE36328....having harder front tires will cause the front end to have less grip!!
I think everyone more or less agreed that you need harder rear suspension, thicker ARB and softer front tires to induce oversteer.
Anyway, for doubters and non believers....I can always arranged a real live demo and see it for yourself. Just pay me RM 50 to recover my tire and nitro fuel cost! :nyehehe: :nyehehe:
I think everyone more or less agreed that you need harder rear suspension, thicker ARB and softer front tires to induce oversteer.
Anyway, for doubters and non believers....I can always arranged a real live demo and see it for yourself. Just pay me RM 50 to recover my tire and nitro fuel cost!
:nyehehe: :nyehehe:
Lee36328
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Adoi, adoi, Albundy,Originally posted by ALBundy@Mar 15 2005, 09:23 AM
Adoi, with all due respect, LEE36328....having harder front tires will cause the front end to have less grip!!
I think everyone more or less agreed that you need harder rear suspension, thicker ARB and softer front tires to induce oversteer.
Anyway, for doubters and non believers....I can always arranged a real live demo and see it for yourself. Just pay me RM 50 to recover my tire and nitro fuel cost!
with all due respect and utmost admiration,....
Bimmerman is correct.... check out his post above....
I do the same thing too.... I pump up my tyres and it would instantly reduce the understeer....
Your second paragraph is also partly correct...
"I think everyone more or less agreed that you need :
1. harder rear suspension (YES),
2. thicker ARB (YES, thicker rear ARB, not front ARB)
3. and softer front tires to induce oversteer (NO, you need harder front tyres, softer rear tyres...)
"
:yes: :yes:
Both Bimmerman and myself have confirmed the front tyre thing via experimentation....
Are you coming to the next TT? We can test our theories together... :beaten:
fabianyee
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the fact that when u pump up the front and reduce understeer. it means your front are not on optimum tyre pressure.... pump up beyond that and see what will happen.. and let us know your findings....Originally posted by Lee36328@Mar 15 2005, 07:50 PM
Adoi, adoi, Albundy,
with all due respect and utmost admiration,....
Bimmerman is correct.... check out his post above....
I do the same thing too.... I pump up my tyres and it would instantly reduce the understeer....
Your second paragraph is also partly correct...
"I think everyone more or less agreed that you need :
1. harder rear suspension (YES),
2. thicker ARB (YES, thicker rear ARB, not front ARB)
3. and softer front tires to induce oversteer (NO, you need harder front tyres, softer rear tyres...)
"
:yes: :yes:
Both Bimmerman and myself have confirmed the front tyre thing via experimentation....
Are you coming to the next TT? We can test our theories together... :beaten:
wirelessjunkie
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OSFlanker
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Guys, correct me if I am wrong, but most road cars are setup to understeer and playing around with the tyre pressure can only do so much. Go in an extra 20kph faster into the same corner and the understeer will probably come back.
I am no automotive expert, have not studied physics beyong Form 5 but from what I have read, understeer and oversteer are caused by slip angles. So to cure understeer, shouldn't you tackle the inherent cause of it rather than the tyre pressure/stiffness? i.e. the suspension geometry. Tyre pressure and spring/absorber rating are just tuning after getting the suspension geometry set , is my understanding correct?
Read the website below to get the low down on handling (someone from the old forum posted this website before).
http://www.autozine.org/technical_school/h...g_4.htm#Neutral
I am no automotive expert, have not studied physics beyong Form 5 but from what I have read, understeer and oversteer are caused by slip angles. So to cure understeer, shouldn't you tackle the inherent cause of it rather than the tyre pressure/stiffness? i.e. the suspension geometry. Tyre pressure and spring/absorber rating are just tuning after getting the suspension geometry set , is my understanding correct?
Read the website below to get the low down on handling (someone from the old forum posted this website before).
http://www.autozine.org/technical_school/h...g_4.htm#Neutral
bimmerman
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Yup, playing with tire pressure can only do so much and is only effective for high speed and medium speed corners. But be warned that things can really get out of hand during high speed corners! You could rip your tires to shreads!!! Or worse still, your rims could catch the tarmac and you could flip over!!! Remember the A-Class Elk test?
When you lower your tire pressure, your sidewall will flex more and it's this flexing motion that causes the tire to lose grip as part of the contact patch is lifted off the ground and grip is compromised.
Tuning via suspension like stiffer ARB for the rear is really the way to go as you're not making compromises like reducing your tires effectiveness which is not a good thing to do for the reason mentioned above.
But since Bazet is making a stunt video, temporarily lowering the rear tire pressure to invoke some oversteer drama should be ok. Unless he's on a Hollywood budget for a total suspension overhaul. :dunno:
p/s: if Bazet flips his car over, it would be one hell of a low budget video with a hollywood budget :rofl:
When you lower your tire pressure, your sidewall will flex more and it's this flexing motion that causes the tire to lose grip as part of the contact patch is lifted off the ground and grip is compromised.
Tuning via suspension like stiffer ARB for the rear is really the way to go as you're not making compromises like reducing your tires effectiveness which is not a good thing to do for the reason mentioned above.
But since Bazet is making a stunt video, temporarily lowering the rear tire pressure to invoke some oversteer drama should be ok. Unless he's on a Hollywood budget for a total suspension overhaul. :dunno:
p/s: if Bazet flips his car over, it would be one hell of a low budget video with a hollywood budget :rofl:
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