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      09-19-2014, 04:27 PM   #1
intoflatlines
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Question More understeer with increased negative camber up front. Am I crazy?

Previous alignment specs were ~1* in front, ~-2* in back. I put camber washers on (and 5mm spacers) to get the front to ~-2.6* in front. On the last autocross I did, I definitely had more instances of understeer. Would more negative camber ever increase understeer or was I probably just pushing the car harder and/or does the more camber perhaps shrink the threshold between grip and no grip in front?
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      10-16-2014, 06:25 PM   #2
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Tires can play a big factor, also how about your toe settings. Ride height, etc. lots of factors too many to speculate.

I can say that going from a stock z4m alignment to a lowered coilover setup with -3.2deg camber in front with 19x9.5et22 front wheels, did not increase under steer one bit. Turn in is amazing.

Although I pay the price at higher speeds do to the aggressive settings.

But I would never switch it up!
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      10-16-2014, 07:08 PM   #3
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Where and when is the understeer coming from (you KNOW this is coming)?

I don't often try to diagnose a problem over the internet, but when I do...

I'm going to guess that your increased "understeer" comes mostly at corner entry just shortly before the end of the braking zone, or shortly after turn-in.

Tell me if I'm right or wrong. If I'm right, I'll answer/explain WHY you're understeering and how to correct it.

If I'm wrong, I'll shut the hell up.
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      10-16-2014, 09:42 PM   #4
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Would more negative camber ever increase understeer or was I probably just pushing the car harder and/or does the more camber perhaps shrink the threshold between grip and no grip in front?

Yes, it can create less if you dont need it (really stiff front springs or sway bar) or you dont let the car take a set, which is where i think is where THE HACK, is going. Car set-up, as Hack mentioned, is nearly impossible to talk about over the internet. One guys over-steer is anothers over steer.

Btw, what is your toe settings which can cause a lot of under steer at turn in, especially if its toed in.
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      10-20-2014, 07:33 PM   #5
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Quote:
Originally Posted by seank View Post
Would more negative camber ever increase understeer or was I probably just pushing the car harder and/or does the more camber perhaps shrink the threshold between grip and no grip in front?

Yes, it can create less if you dont need it (really stiff front springs or sway bar) or you dont let the car take a set, which is where i think is where THE HACK, is going. Car set-up, as Hack mentioned, is nearly impossible to talk about over the internet. One guys over-steer is anothers over steer.

Btw, what is your toe settings which can cause a lot of under steer at turn in, especially if its toed in.
*Or even too much toe-out...which I doubt is probably the case here.

OP - Do you know your caster settings?
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      01-03-2016, 12:20 AM   #6
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Quote:
Originally Posted by The HACK View Post
Where and when is the understeer coming from (you KNOW this is coming)?

I don't often try to diagnose a problem over the internet, but when I do...

I'm going to guess that your increased "understeer" comes mostly at corner entry just shortly before the end of the braking zone, or shortly after turn-in.

Tell me if I'm right or wrong. If I'm right, I'll answer/explain WHY you're understeering and how to correct it.

If I'm wrong, I'll shut the hell up.
care to explain why? lol
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      01-03-2016, 12:06 PM   #7
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Quote:
Originally Posted by AriuSen View Post
care to explain why? lol
Man that post was made so long ago I almost forgot why I said it.

A lot of negative camber up front, or at least, going from where stock-ish camber is to a ton of negative camber up front, takes some getting used to. The reason is under static load, the camber actually changes the shape of the contact patch and leads to REQUIRING the front end to load up some weight before the brakes will have full traction of the tires to work with.

So if you're used to getting on the brakes very quick with minimal camber, the result is when you brake hard, the front end compresses and you get additional camber to work with on turn-in. With ADDED camber, if you brake hard and fast, you will cause the front end to lose grip initially since the shape of the contact patch is no longer ideal for braking. You will need to re-learn your braking to allow the weight to transfer to occur at the right time. Cars with a ton of negative camber will require the braking to be done LATER and trailed into the turn, so that you're sort of braking and turning at the same time to maximize the contact patch. But you can't brake as hard, and you won't need to brake as hard, since the added camber will allow you to corner at a higher speed.

The end result, is if you brake TOO hard with a ton of camber going into a turn, you may experience understeer when the front brakes overwhelm the front tires on corner entry.

The truth about going fast is all about managing your contact patch, and learning to brake ONLY ENOUGH to manage those contact patches.
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      01-03-2016, 12:23 PM   #8
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Quote:
Originally Posted by The HACK View Post
Man that post was made so long ago I almost forgot why I said it.

A lot of negative camber up front, or at least, going from where stock-ish camber is to a ton of negative camber up front, takes some getting used to. The reason is under static load, the camber actually changes the shape of the contact patch and leads to REQUIRING the front end to load up some weight before the brakes will have full traction of the tires to work with.

So if you're used to getting on the brakes very quick with minimal camber, the result is when you brake hard, the front end compresses and you get additional camber to work with on turn-in. With ADDED camber, if you brake hard and fast, you will cause the front end to lose grip initially since the shape of the contact patch is no longer ideal for braking. You will need to re-learn your braking to allow the weight to transfer to occur at the right time. Cars with a ton of negative camber will require the braking to be done LATER and trailed into the turn, so that you're sort of braking and turning at the same time to maximize the contact patch. But you can't brake as hard, and you won't need to brake as hard, since the added camber will allow you to corner at a higher speed.

The end result, is if you brake TOO hard with a ton of camber going into a turn, you may experience understeer when the front brakes overwhelm the front tires on corner entry.

The truth about going fast is all about managing your contact patch, and learning to brake ONLY ENOUGH to manage those contact patches.
that is a good explanation....I agree with that too. thanks
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