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Looking to Reduce Oversteer

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Old 08-11-2006, 01:47 PM
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I dont quite understand what you mean by where am i ending up relative to the outside of the track, but if i think i know what you are asking; I end up just about 1 ft from the outside of the track at exactly the exit point i wanted (which is actually where i wanted it to go). I dont require extra input, only unwinding slightly as needed closer and closer to the end of the corner (as normal). My guestimate is not enough throttle as when i am rougher, i seem to be heavier on the throttle.

As for Drivers education classes and "racing" classes, I have a few along side my competition license for canada (C license for CASC). Now most of those clases was done with the civic racer, and only 1 (which actually happened to be the class to get my C license) with the s2000 and didnt have too many problems, but also due to it was the 1st time i had it on the track and was maby pushing 7-8/10ths.

Tire pressures I will be adjusting next lapping day to test. As for alignment, I have been told my alignment is gold for neutral handeling:

Front

Caster
L 6.10 degrees
R 6.21 degrees

Camber
L -0.34 degrees
R -0.37 degrees

Toe
L 0"
R 0"
Total 0"


Rear

Camber
L -2.44 degrees
R -2.46 degrees
Toe
L 1/8" (toe in)
R 1/8" (toe in)
Total 1/4" (toe in)


I do agree I need somoene to get in with me and advise, but everytime I get someone either they are too nice and just say you are fine, or they say you dont need to improve (which i highly doubt that that is the case. In my books, any driver with under 5 years experience is still learning on a diminishing curve)
Old 08-11-2006, 01:49 PM
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Now I am not able to get a lot of track time, and I am testing some of these methods on the streets I am extremly familiar with and still get similar results as I would from the track.

Note I made a mistake on the tire listed above,

it is Hankook Z212 205/55/16 F 35 Psi
245/45/16 R 33 Psi

What would be the handling characteristics, Cateris Paribus (all things being equal), when balencing tire pressures. **for some reason I can never remember*

higher pressure in front would result in the car ....oversteer/understeer/neutral
Higher pressure in the rear would result in the car ___________
Too high in front relative to rear ______________
Too high in rear relative to front _______________
Old 08-11-2006, 02:08 PM
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Suspension Geometry ???
Old 08-11-2006, 03:16 PM
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Originally Posted by ^AnDre^,Aug 11 2006, 05:49 PM
Now I am not able to get a lot of track time, and I am testing some of these methods on the streets I am extremly familiar with and still get similar results as I would from the track.

Note I made a mistake on the tire listed above,

it is Hankook Z212 205/55/16 F 35 Psi
245/45/16 R 33 Psi

What would be the handling characteristics, Cateris Paribus (all things being equal), when balencing tire pressures. **for some reason I can never remember*

higher pressure in front would result in the car ....oversteer/understeer/neutral
Higher pressure in the rear would result in the car ___________
Too high in front relative to rear ______________
Too high in rear relative to front _______________
I'll take a stab at this one. I have no idea about the actual ideal air pressure for the Hankooks. It is hard to tell you higher pressure = better grip since it depends on the tire construction. In general this is how it works.

1) Tire grip increases slowly with increasing pressure. This is due to the air pressure stabilizing the tire contact patch, giving better grip. Tires with soft sidewalls need more air pressure to keep them stable.

2) Once you get to the optimum grip level, adding more pressure quickly decreases your grip. This is from the decreasing tire patch from the tire balloning making the contact patch smaller.

3) On the track it is the hot pressure that matters. So the best cold pressures that is typically talked about, depends on the driver and conditions. If it is wet and cold, higher cold pressures. Hot day driving hard, lower cold pressures.

So, the goal is to get the lowest pressure possible (for bigger contact patch) that still keeps the tire patch stable. It's a little different for drag racing, but we're not talking about that. The optimum pressures are different for each tire, so it's for you to experiment with unless there is someone out there with the same setup as you. If you are testing on the street, you will probably find that at the track the cold pressures will be lower, since you should be driving harder causing tire temperature rise to be greater.
Old 08-11-2006, 03:32 PM
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The alignment and tire stagger smells like understeer to me.

The big difference in camber between the front and rear tires make me think though. Depending on how grippy your tires are, I'm thinking that your handling balance might change from a high G corner to a low G corner from the difference in how much the car rolls. Take that for what its worth. I'm talking out of my ass right now.
Old 08-11-2006, 04:12 PM
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Originally Posted by ^AnDre^,Aug 11 2006, 02:47 PM
I do agree I need somoene to get in with me and advise, but everytime I get someone either they are too nice and just say you are fine, or they say you dont need to improve.
You are asking the wrong people. I know at least 4-5 instructors who could really dismember my driving style any time I managed to get them into the car with me. The problem is that they are in demand by everyone else, too.

At any rate, before the instructor gets in the car with you tell him/her exactly what you are concerned with and that you don't want to have your feelings coddled.
Old 08-12-2006, 07:26 AM
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Fongu, I can somewhat agree to that. So what do you suggest is a better camber for front and rear, or better yet, total alignment specs?
Old 08-12-2006, 08:26 AM
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I agree with Fongu, from your alignment specs and your tire pressures it looks like you have a recipe for understeer not oversteer. My alignment is very aggressive so take it with a grain of salt but I'm maxed out front camber (~-2 deg) and rear (~-2.5) with the same caster and toe in as you.

Theoretically more front camber will give you more front grip up to a certain point. I'm not sure if you mentioned this or not, but are you on a stock suspension? Another thing, are the tires the same age, ie are the rear tires much older than the fronts? They may just be heat cycled out.

Over here in SoCal , track temps can be 100+ degs . I've had this problem with Bridgestone S-03's which can't take the heat from track driving and start to chunk. No matter what I did with tire pressures and alignment I would have the rear end step out on me randomnly. When I switched to RA1's it went away.
Old 08-14-2006, 08:36 AM
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The suspension is stock.

I am noticing that on the street it is feeling more like a neutral to slight push understeer (depending how I attack the corner) to oversteer (with no tire squeal) on the exit.

the tires are not the same age. Maby 2 weeks apart (originally purchased 225's for the rears and sourced out some 245's). There is no chunking at all, but they are appearing to be getting squarer around the edges (Front and rear), but good tread left. I am doubting that they are heat cycled out, unless the z212 hankook's cycle easily and on the street.

So what you are trying to tell me is that more negative camber in the front and close to the same in the back will handle better, but is more agressive (in what terms agressive?).
Old 08-16-2006, 01:18 PM
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Well, I just brought it to the local alignment shop (who works on alot of track cars and comes highly recommended), and he tells me that the alignment wasnt exactly as I had stated (or should have been). Caster was only at 5 (looks like my other guy didnt do a good job) and toe had migrated (but he didnt mention wich way). Now with 6.3 caster in the front and -1.5 camber front and -2.5 in the rear (toe in 1/8" each side). Now the steering is much heavier and feels more direct, but at the same time it feels delayed. Previously the steering was lighter but seemed to need less input to make the same turn. Now it feels heavier and requiring more input, maby i am not used to it yet (only drove it for an hour and didnt get many turns in... dam traffic...). Im going to do some tests on some corners where i know my exact cornering speed and limits on the way home.. it'd be interesting to see what happens at this point.

I am noticing now with this alignment that the car handles MUCH better and the oversteer is way more controllable. However I am noticing that the rear under compression seems to swiggle a bit on the way down. There is no real loss of traction, but it feels unsetteling. What would be the reasoning for this or is this just normal. FYI I have orderd a set of Bilstein PSS9. It'd be nice to see how they work when they come in at the end of this month.
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