I went to the auto-X for my first time this weekend. It was awsome :ylsuper but...now I'm addicted. I want to get my times down and I know if my car didn't under stear so freaken much it would do awsome. Currently I am running:
92 se hatch/SR , KYB GR2 Struts w/eiboch sportlines, front strut tower bar, and open diff (no lsd)
If anyone could give me a few pointers on what to buy next or what to change to get my car to turn when I want it to turn please let me know.
How do I correct Under Stear?
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WongFeiHung
- Posts: 341
- Joined: Sun Mar 16, 2003 7:25 pm
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Hijacker
- Posts: 14373
- Joined: Wed Aug 13, 2003 4:57 am
- Car: '92 240sx Convertible
'94 F-150 - Location: Fredericksburg, VA
i'm surprised you were understeering. 240's have a tendency to oversteer IMO which is why they're chosen to drift with in Japan.
better tires will help. Your fronts could be balding or just can't give enough grip to turn the car. after that would be new shocks and springs, then new sway bars and a strut tower bar. there's a great article on Project Silvia over at sportcompactcarweb.com where they tune the suspension to their 240.
better tires will help. Your fronts could be balding or just can't give enough grip to turn the car. after that would be new shocks and springs, then new sway bars and a strut tower bar. there's a great article on Project Silvia over at sportcompactcarweb.com where they tune the suspension to their 240.
tenkawa_akito wrote:i'm surprised you were understeering. 240's have a tendency to oversteer IMO which is why they're chosen to drift with in Japan.
Keiichi Tsuchia (Drift King, Dori Dori) makes it a point in his Best Motoring Drift Bible that the S13 is an understeery car and to correct that suspension modification and driver skill are necessary to counteract this. I notice a fair amount of understeer in my old stock suspension on longer sweepers, but in tight turns, because my rear tires are shot, oversteer in quick, but easily ended thanks to my evil open diff.
I would also say look at adjustable tension rods. Mabye pick up a HICAS sway bar. $88 from http://www.car-part.com (search for stabilizer bar, rear 4 wheel steering) as it is a little thicker than the stock one and cheap.
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WongFeiHung
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C-Kwik
- Moderator
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- Joined: Thu Aug 01, 2002 9:28 pm
- Car: 2013 Chevy Volt, 1991 Honda CRX DX
To fix understeer or any handling problem, you must figure out WHY it is understeering.
Just of couple of points and counter-points to various things that have been said.
More right foot will only add to understeer unless you get to a point where you force the rear tires to lose traction. When understeering already, it's not the easiest thing to do unless you have gobs of power. Basically trying to speed up while maintaining the same line will just load the front tire even more.
Larger rear sway bars may help, but ultimately, if weight balance between the front and rear wasn't the biggest contributing factor, then it won't make that big of a change. A large enough rear bar may cause oversteer, but the front tires still won't be making any more grip.
Take a look at your tires. Does it show signs of wear in the transition area between the tread and the sidewall? A little is normal close to the tread. Too high on the sidewall and you have camber issues...or lack of negative camber issues to be more accurate. This seems to be the most common reason for understeer in a 240. Making sure the contact patch stays flat helps to make the most grip. Getting the front tires to grip more would be the optimal way to reduce your problem since you'll be able to take turns faster and/or it will reduce the heat in the front tires.
Also reducing front end body roll can actually help reduce understeer. Keeping compression in the front suspension low during a turn will help keep the tires more upright with the road. The more the car leans, the more positive camber the outside front tire will see during a turn. This is not much of an issue with double wishbone or multilink suspensions since these add some camber during compression.
As far as tire pressure, this is best figure by using a pyrometer. Watch the guys at the autocross. Many of them will be checking their pressures immediately after a run and making adjustments. The key here is to try and get the most even heat possible across the tread.
Just of couple of points and counter-points to various things that have been said.
More right foot will only add to understeer unless you get to a point where you force the rear tires to lose traction. When understeering already, it's not the easiest thing to do unless you have gobs of power. Basically trying to speed up while maintaining the same line will just load the front tire even more.
Larger rear sway bars may help, but ultimately, if weight balance between the front and rear wasn't the biggest contributing factor, then it won't make that big of a change. A large enough rear bar may cause oversteer, but the front tires still won't be making any more grip.
Take a look at your tires. Does it show signs of wear in the transition area between the tread and the sidewall? A little is normal close to the tread. Too high on the sidewall and you have camber issues...or lack of negative camber issues to be more accurate. This seems to be the most common reason for understeer in a 240. Making sure the contact patch stays flat helps to make the most grip. Getting the front tires to grip more would be the optimal way to reduce your problem since you'll be able to take turns faster and/or it will reduce the heat in the front tires.
Also reducing front end body roll can actually help reduce understeer. Keeping compression in the front suspension low during a turn will help keep the tires more upright with the road. The more the car leans, the more positive camber the outside front tire will see during a turn. This is not much of an issue with double wishbone or multilink suspensions since these add some camber during compression.
As far as tire pressure, this is best figure by using a pyrometer. Watch the guys at the autocross. Many of them will be checking their pressures immediately after a run and making adjustments. The key here is to try and get the most even heat possible across the tread.
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Scott McLellan
- Posts: 299
- Joined: Sat Nov 23, 2002 7:53 am
Also make sure you are braking before the turn and not during. Any car will push if you go into the turn to fast and try and slow down during the turn. A LSD would do wonders for you, I have one. I think this would have been a better investment than the sway bar but the sb will probly help a little.
Gmans13 wrote:yeah deffinatly the lsd is going to be my next investment. I just got the sway bar now because I came up on it for a good price. Thanks for all the other tips guys
try and learn the apex of a turn as best you can so understeer doesn't happen as much. once you can master turns w/o an lsd and eliminating as much understeer as possible, then intall a lsd and since you already have the experience everything will be that much easier to you.