Best alignment settings - educate me please

[Bull]

I have a 2021 Plaid and have excess negative rear camber (approx -2.7) wearing the inside edges of my tires (Michelin PS4S) after only a few thousand miles. I recently broke down and ordered the N2itive TARTAN SX-P2 2021+ Tesla Model S/X PLAID & Long Range Forged Adjustable Rear Upper Camber Arms which will be shipping next week. Once I install them I'm taking the car to my SC (probably) for specific alignment.

I would appreciate advice / opinions on the best settings for my driving style. I do not track or autocross my car. I drive some highway, spirited street, and occasional 1/4 mile drag racing so I do want good stability at speed. Occasional winding mountain roads are fun but I do not drive them to the cars limits.

So far I'm thinking this (low position without lowering links):
Front camber: -0.5°
Front toe: -0.05°

Rear camber: -0.8°
Rear toe: 0.05°

Will these setting be best for 'spirited' cornering and straight line stability while keeping my tires flatter on the ground for more even wear and better traction on the drag strip? What would you change?

@N2itive @lolachampcar @n2mb_racing @MFrunkerOG @lbowroom @jebinc

 

[lbowroom]

I have a 2021 Plaid and have excess negative rear camber (approx -2.7) wearing the inside edges of my tires (Michelin PS4S) after only a few thousand miles. I recently broke down and ordered the N2itive TARTAN SX-P2 2021+ Tesla Model S/X PLAID & Long Range Forged Adjustable Rear Upper Camber Arms which will be shipping next week. Once I install them I'm taking the car to my SC (probably) for specific alignment.

I would appreciate advice / opinions on the best settings for my driving style. I do not track or autocross my car. I drive some highway, spirited street, and occasional 1/4 mile drag racing so I do want good stability at speed. Occasional winding mountain roads are fun but I do not drive them to the cars limits.

So far I'm thinking this (low position without lowering links):
Front camber: -0.5°
Front toe: -0.05°

Rear camber: -0.8°
Rear toe: 0.05°

Will these setting be best for 'spirited' cornering and straight line stability while keeping my tires flatter on the ground for more even wear and better traction on the drag strip? What would you change?

@N2itive @lolachampcar @n2mb_racing @MFrunkerOG @lbowroom @jebinc

Not sure you can get that little camber in the front. I’m lowered -6 in the front and the minimum adjustable camber is -1.2. No wear issues. Then again as I’ve mentioned before I have no wear issues in the rear at -2.2 either on non OEM rears.

There’s obviously more to this problem than the camber angle.

Looking forward to see if Sam1’s Goodyears actually delaminate and split or just wear out on the inside

 

[MFrunkerOG]

If you have 21” wheels that is likely a different problem causing the wear on the inner wheel edge at the back.

My wheels for driving like you mentioned are at neg 2.25 Camber all round, toe in 0.05 all round. I don’t think your settings will be enjoyable as your suspension rubber bushings will twist under compression.

 

[Aggmeister2010]

IMO, you need a little more negative camber than that. I have mine at -1.2 degrees all around. I also have a little more toe front/rear, but that's more of a preference thing.

 

[Bull]

Not sure you can get that little camber in the front. I’m lowered -6 in the front and the minimum adjustable camber is -1.2. No wear issues. Then again as I’ve mentioned before I have no wear issues in the rear at -2.2 either on non OEM rears.

There’s obviously more to this problem than the camber angle.

Looking forward to see if Sam1’s Goodyears actually delaminate and split or just wear out on the inside

My fronts currently wear pretty evenly. I got 25k miles on those. I did not measure the camber but it is definitely less than the rears.

I have not had alignment done on this car yet so wrong toe could be aggravating the inside wear with that camber angle. This is the rear I just replaced after <4,000 miles.

 

[Bull]

If you have 21” wheels that is likely a different problem causing the wear on the inner wheel edge at the back.

My wheels for driving like you mentioned are at neg 2.25 Camber all round, toe in 0.05 all round. I don’t think your settings will be enjoyable as your suspension rubber bushings will twist under compression.

I should have mentioned that I do have 21" wheels. Since I have not done an alignment yet you could be right about teh issue being a different problem. I'll know more after the adjustable upper camber arms arrive and I get that first alignment.

 

[Bull]

IMO, you need a little more negative camber than that. I have mine at -1.2 degrees all around. I also have a little more toe front/rear, but that's more of a preference thing.

I suspect that I will play with different settings for a while. I'm looking for optimal initial settings right now that cover spirited street and drag racing. Since those things need different settings I'm trying to find the best balance. -1.2 degrees would still be significantly better than I have now.

What does more toe give you that you prefer? Better straight line stability?

 

[lbowroom]

I would keep the toe negative (toe in)

 

[MFrunkerOG]

I should have mentioned that I do have 21" wheels. Since I have not done an alignment yet you could be right about teh issue being a different problem. I'll know more after the adjustable upper camber arms arrive and I get that first alignment.

there is a thread on tmc called “Plaid 21” rear tire woes”. You’ll find almost exact pictures of your rear tire over there and a lot of debate - some of the banter there is mine

On camber, I can’t speak for the n2itive arms because I don’t have them - I cancelled my order after months of waiting and went the MPP route.

Also the current camber you have at medium suspension height is less negative than what happens at low setting (all highway is low now I think)

 

[Bull]

I would keep the toe negative (toe in)

For both front and rear?

 

[SignatureSales]

Ideally you want a bit more negative camber in the rear. Anything below -2.0 should not give you any excessive tire wear. ( our Plaid is lowered at -6 on N2itive, rear is at -1.9 degree. No sign of excessive wear after 12k miles)

Most owner experience in “inner shoulder wear” like below, which is most likely to cause by toe not camber.

Like @lbowroom mentioned, you want the rear to be toe in, as toe will get push outward ( Toe-out) under acceleration.

Pic is provided by one of the TMC member:

 

[Sam1]

Ideally you want a bit more negative camber in the rear. Anything below -2.0 should not give you any excessive tire wear. ( our Plaid is lowered at -6 on N2itive, rear is at -1.9 degree. No sign of excessive wear after 12k miles)

Most owner experience in “inner shoulder wear” like below, which is most likely to cause by toe not camber.

Like @lbowroom mentioned, you want the rear to be toe in, as toe will get push outward ( Toe-out) under acceleration.

I was blaming camber only too, but after recording videos with a gopro of the rear tires, you can clearly see the entire front of the tire flexing out significantly. But, on other videos of the built in tesla cameras, you can see the outside tread barely touching the pavement under load (load = racing in this case)

I now believe it's a combination of the two issues.

The camber arms may not fix the issue, but it may change the geometry enough to minimize the damage caused by toe. & that's why people with the arms that have done an alignment in the low setting, aren't seeing issues anymore.

 

[Sam1]

This is how little tread on the outside is touching the pavement under a full throttle launch. Probably around the 60 foot mark when it looked like this.

 

[Aggmeister2010]

Toe out in the front gives more stability in turning because you have a leading tire - but you'll have to make more micro-corrections when traveling in a straight line at highway speed. With neutral toe, your turn-in will suffer a bit, but you'll have a more laser-straight drive on the freeway.

Pick your poison.

The rear toe should be IN either way or the back end will wander around.

Like SignatureSales said, most people that suffer from excessive inner edge wear have too much TOE, not necessarily too much camber.

 

[Bull]

Ideally you want a bit more negative camber in the rear. Anything below -2.0 should not give you any excessive tire wear. ( our Plaid is lowered at -6 on N2itive, rear is at -1.9 degree. No sign of excessive wear after 12k miles)

Most owner experience in “inner shoulder wear” like below, which is most likely to cause by toe not camber.

Like @lbowroom mentioned, you want the rear to be toe in, as toe will get push outward ( Toe-out) under acceleration.

Pic is provided by one of the TMC member:

I am expecting to play with the rear camber a bit. I have had issues with tire slip on the drag strip and expect that getting the tires flatter on the ground will help resolve that. But I do know that 0 degree rear camber is not good for daily street driving and cornering. I'm guessing that I will end up somewhere between -1 and -2 degrees rear camber.

I am set on rear toe in but unsure about the front toe. I'm leaning toward neutral or slightly in for front for stability at very high straight line speeds.

 

[Bull]

This is how little tread on the outside is touching the pavement under a full throttle launch. Probably around the 60 foot mark when it looked like this.

View attachment 890225

This is exactly what I think is happening to me when launching at the drag strip. My 60' times have been poor and too much tire slippage.

 

[Bull]

Toe out in the front gives more stability in turning because you have a leading tire - but you'll have to make more micro-corrections when traveling in a straight line at highway speed. With neutral toe, your turn-in will suffer a bit, but you'll have a more laser-straight drive on the freeway.

Pick your poison.

The rear toe should be IN either way or the back end will wander around.

Like SignatureSales said, most people that suffer from excessive inner edge wear have too much TOE, not necessarily too much camber.

Clearly one thing I am missing here is knowing what my current toe is. This car is still on the factory alignment. The wear problem could easily be mostly a toe problem as Jamie and others have pointed out.

Less negative camber will help with traction at launch. Now I just need to decide on front toe. Looks like either neutral or slightly in for the front will be best for my needs. I don't want to have to be doing any more corrections than necessary at >150 mph.

 

[Bull]

there is a thread on tmc called “Plaid 21” rear tire woes”. You’ll find almost exact pictures of your rear tire over there and a lot of debate - some of the banter there is mine

On camber, I can’t speak for the n2itive arms because I don’t have them - I cancelled my order after months of waiting and went the MPP route.

Also the current camber you have at medium suspension height is less negative than what happens at low setting (all highway is low now I think)

I did read that and others. Since my question was more about optimal settings for a car that was daily driver and straight line raced and not tracked. I thought a separate thread would be helpful.

I see that you posted:
For the rear I went from -2.5ish to -1.5 camber
For the front I went from -0.5 to -1.3 camber
and then a month later you posted that you switched to -2 degrees in front and that was your new favorite.

What was the difference that you liked so much after switching to -2 degrees in front?

 

[MFrunkerOG]

I did read that and others. Since my question was more about optimal settings for a car that was daily driver and straight line raced and not tracked. I thought a separate thread would be helpful.

I see that you posted:
For the rear I went from -2.5ish to -1.5 camber
For the front I went from -0.5 to -1.3 camber
and then a month later you posted that you switched to -2 degrees in front and that was your new favorite.

What was the difference that you liked so much after switching to -2 degrees in front?

The difference was that the car was handling around turns / curves so much more better at -2 ish all round, so I have stayed at that level. It’s been 5k miles I think since then and my wear is quite even on all 4 tires, I don’t have the dreaded inner tire wear either.

Yes I have a whole bunch of MPP parts too. This is now the best driving / handling car I have ever had the pleasure of driving

 

[Sam1]

This is exactly what I think is happening to me when launching at the drag strip. My 60' times have been poor and too much tire slippage.

I get much better times with the 19" tires on there because they stay planted all the way across.