# Optimum Alignment settings for Lowered TT?



## tfifeco (Aug 4, 2014)

I posted this question in my build thread but may not be getting enough exposure.

I have the PSS9 system and just removed the helper springs in front and the adjuster nut in rear so now i am about as low as i can be without rubbing. Running 18" tires. 

I am going to take the car to an alignment shop that has a lot of experience with these type of alignments

My question is what are the optimum settings for camber and toe angles for regular daily street use. I red on one of the suspension threads that the rears should have a slight Toe In ... around 1/32 and the camber at about -1.2 but that discussion was mainly geared around Track and Autocross... on a lowered TT (Not Slammed, but close) should i be targeting the same setting for Regular daily street use?

Thanks in advance
Trey


----------



## TheDeckMan (Sep 26, 2004)

Trey,

What I run for street/track

Front toe total -.02-.10°
Rear toe total .44° 
Front camber -1.5-1.7°
Rear camber -1.1-1.3°

This past year I ran with great dry track times, however its a little more tricky to drive in the rain and edgy on the street. Note the rear toe angle is less which means the front edge of the rear tires is closer to 0° than the street setup with the .44° setup which has the rear toe in much more for better stability and driving in bad weather.

Track only

Front toe total .15°
Rear toe total .24° 
Front camber -1.8°
Rear camber -1.3°


----------



## Marcus_Aurelius (Mar 1, 2012)

Needs more front camber Noah! What's the logic behind the positive front toe? Seems counterproductive for what you do with the car -- if anything, some negative tracking (toe out) in the front would make sense to improve turn in (although at the expense of tire life). 

Rear is on point though... :thumbup:


Below, I'm quoting my response in your thread for some solid street/track settings:



Marcus_Aurelius said:


> You want to aim for:
> 
> *Front
> *zero toe
> ...


PS: Careful with toe settings in degrees. Sometimes alignment places like to use total toe as their reference. Angle in degrees is fine as a measurement, but when the degree angles are uneven left/right and the operator only cares about total toe of both wheels, the uninitiated can be easily fooled. It's hard to miss imbalances when individual fraction of an inches are used. :beer:


----------



## tfifeco (Aug 4, 2014)

Marcus_Aurelius said:


> Needs more front camber Noah! What's the logic behind the positive front toe? Seems counterproductive for what you do with the car -- if anything, some negative tracking (toe out) in the front would make sense to improve turn in (although at the expense of tire life).
> 
> Rear is on point though... :thumbup:
> 
> ...


Ok Thanks Max, Yeah i started this thread before i realized you replied to my build thread... Wasnt sure if it was getting much exposure.

also didnt realize the front camber should be that much more negative than the rears, seems like a lot but i will go with those setting, you're the suspension guru not me :laugh: but will that much negative camber in from -2.3 to -3.0 cause excessive tire wear? Just curious

thanks for the replies


----------



## TheDeckMan (Sep 26, 2004)

Marcus_Aurelius said:


> Needs more front camber Noah! What's the logic behind the positive front toe? Seems counterproductive for what you do with the car -- if anything, some negative tracking (toe out) in the front would make sense to improve turn in (although at the expense of tire life).
> 
> Rear is on point though... :thumbup:
> 
> ...



Agree on the front camber, believe it or not that I am getting a very nice tire wear on the NT-01's with that setting. No idea why I like that toe setting, but it feels right, something I carried over from Dick Shine. The overall toe out was a total, so about .07° each which always seems to help the turn in but at perhaps a slight bit of scrubbing under high load situations, I tried 0° but found the left hander at Lime Rock a little more difficult with more input needed. However with doing Palmer this year I am going to bring it back to 0° and adjust the camber a little more on the front with some plates. 

As you pointed out all my measurements were in totals. The old shine trick was about 1/16"-1/32" toe out in the front.


----------



## Marcus_Aurelius (Mar 1, 2012)

DeckManDubs said:


> Agree on the front camber, believe it or not that I am getting a very nice tire wear on the NT-01's with that setting. No idea why I like that toe setting, but it feels right, something I carried over from Dick Shine. The overall toe out was a total, so about .07° each which always seems to help the turn in but at perhaps a slight bit of scrubbing under high load situations, I tried 0° but found the left hander at Lime Rock a little more difficult with more input needed. However with doing Palmer this year I am going to bring it back to 0° and adjust the camber a little more on the front with some plates.
> 
> As you pointed out all my measurements were in totals. The old shine trick was about 1/16"-1/32" toe out in the front.


Maybe there is a typo in your text but you have positive toe listed (0.07) which would be toe-in ... not toe-out. The old Shine trick you're referring to is suggesting negative toe which would be -0.07 total toe. If you're in fact running .07 you're doing the opposite of what you're after and what's suggested by Shine. I can see a smidge of negative tracking (toe-out) helping turn in, but toe-in is guaranteed to have the opposite effect on a steering axle.


----------



## TheDeckMan (Sep 26, 2004)

Marcus_Aurelius said:


> Maybe there is a typo in your text but you have positive toe listed (0.07) which would be toe-in ... not toe-out. The old Shine trick you're referring to is suggesting negative toe which would be -0.07 total toe. If you're in fact running .07 you're doing the opposite of what you're after and what's suggested by Shine. I can see a smidge of negative tracking (toe-out) helping turn in, but toe-in is guaranteed to have the opposite effect on a steering axle.


Yep, its a typo. It is -.07


----------



## Marcus_Aurelius (Mar 1, 2012)

tfifeco said:


> Ok Thanks Max, Yeah i started this thread before i realized you replied to my build thread... Wasnt sure if it was getting much exposure.
> 
> also didnt realize the front camber should be that much more negative than the rears, seems like a lot but i will go with those setting, you're the suspension guru not me :laugh: but will that much negative camber in from -2.3 to -3.0 cause excessive tire wear? Just curious
> 
> thanks for the replies


No, static -3 degrees of camber is not excessive and will NOT wear your outside tires prematurely (unless you never take turns). For instance I was getting pretty even front tire wear when my car was daily driven at -5.0 degree of static camber compensation -- and that's with some additional caster (aka dynamic camber) on top of it. That's why I sometimes tell people with confidence to simply max out their front plates for camber, the known plates in the market don't offer adjustments past -3 degrees alone without some other forms of camber compensating components/modifications.


----------



## Marcus_Aurelius (Mar 1, 2012)

DeckManDubs said:


> Yep, its a typo. It is -.07


Makes sense and reconcile everything now! Something wasn't adding up and not letting my brain process it ... you know how we techies get.


----------



## tfifeco (Aug 4, 2014)

Ok so i am going to shoot for these settings

You want to aim for:

Front
zero toe
-2.5 to -3.0 camber
Maximum caster you can afford (your plates dependently adjusts both parameters).

Rear
1/16" toe in
-1.5 camber 

But just for my education and understanding ... For Track Purposes only you guys are suggesting (forget positives and negatives for a sec) for the Front a slight Toe-Out and for the Rears a slight Toe-in ???? i can wrap my head around Toe-in/Toe-out................. Why would you not want the Toe to be dead zero for front and rear? is it more specific to the suspension geometry of the TT? or is that common across many track cars?


----------



## TheDeckMan (Sep 26, 2004)

Marcus_Aurelius said:


> Makes sense and reconcile everything now! Something wasn't adding up and not letting my brain process it ... you know how we techies get.


fixed


----------



## Marcus_Aurelius (Mar 1, 2012)

tfifeco said:


> But just for my education and understanding ... For Track Purposes only you guys are suggesting (forget positives and negatives for a sec) for the Front a slight Toe-Out and for the Rears a slight Toe-in ???? i can wrap my head around Toe-in/Toe-out................. Why would you not for the Toe dead zero for front and rear? is it more specific to the suspension geometry of the TT? or is that common across many track cars?


Toe out in the front helping with turn-in ability is hard to explain without going deep into it. It's really a battle between yaw moments vs steering wheel/tire angles (technically called slip angles). Toe out generally improves yaw moment for any steering input, and that's what is universally felt (more responsive to steering might be a better phrase to use in describing it). 

But why does it have that effect? Slip angles (up to a point) positively helps thrust (basically what forces the car to change direction because of rubber friction on the ground). So, say 1 degree of slip angle equals to X unit of thrust forces -- then 2 degrees of slip angles gives you X +1 unit thrust forces. If you're still with me, let's model a TT with zero front toe vs Noah's with -0.07 toe out added:

-The TT with zero toe going through a turn at the track (with 1* of steering angle) will generate say .85 lateral G. This is with the outside tire doing most of the work when the inside one which has the greater ability to pull you in isn't doing as much as it could (remember inside and outside wheels are parallel to each other with zero toe).

-Now let's look at Noah's TT with some toe-out going through that same turn (still with that arbitrary 1* of steering angle). It generates 0.90 of lateral G (let's assume all else is also equal) because the inside tire is doing much more work. Why so? His static toe out already compensated by pointing that inside tire towards the turn (although the outside tire was also pointing away from the turn now), in return it helped the inside tire exponentially add to its thrust forces (aka grip). Some will ask about what happens to the outside tire then? Well first of all, compression toes tires inward with most passenger bound vehicles including the TT - so with weight transfer, the outside tire already has the capacity to dynamically point itself towards the direction of the turn, therefore the small static toe out compensation doesn't nearly affect things as much as it could. Secondly, outside tires in a turn tend to be overloaded, this means they are already near or past what they can physically do in terms of thrust. Therefore making the inside tire do more work is ten times more beneficial than the small compromise the toe out is to an outer tire during cornering. 



Thankfully, toe-in in the back is easy to comprehend and explain since it's operating in a somewhat static (in terms of steering angles) or non-steering axle. So I t's really becomes more of a balance thing since pointing both tires inward (toe-in) adds lateral stability, and pointing both tires outward (toe-out) removes rear stability. So, this case is when things are a bit more chassis-specific. To generalize, cars with some TQ transferred to the rear wheels (RWD and AWD) are almost always going to benefit from some toe-in as it helps tame the back end laterally at high speed and specifically under throttle. On the opposite end of the spectrum, track cars that struggle for rotation (think FWD) might venture out with zero rear toe or even some toe out as a compromise to help inherent push in slower corners (although very high speed corners and braking from front straights becomes more squirrelly the added help in slower stuff is better overall).


----------



## tfifeco (Aug 4, 2014)

Marcus_Aurelius said:


> This is with the outside tire doing most of the work *when the inside one which has the greater ability to pull you in*_{to the turn}_ isn't doing as much as it could


Ok It just clicked.... Light Bulb!!!! when i read that part of your explanation :beer:

so for normal _aggressive red light to red light_ :laugh: street driving ... Zero Toe will be jiist fiiiiine


----------



## Marcus_Aurelius (Mar 1, 2012)

tfifeco said:


> Ok It just clicked.... Light Bulb!!!! when i read that part of your explanation :beer:
> 
> so for normal _aggressive red light to red light_ :laugh: street driving ... Zero Toe will be jiist fiiiiine


Bingo, that's why zero front toe is my recommendation for the street and occasional track action (keep in mind that tire life also decreases with toe out. Much more so than the camber you were worrying about anyway). :beer:


----------



## 91MK2Jetta (Jul 25, 2012)

0 toe, -3 camber up front, and -6 camber in the rear


----------



## Marcus_Aurelius (Mar 1, 2012)

91MK2Jetta said:


> ... and -6 camber in the rear


The forum thanks you for your very thoughtful post... it really is the embodiment of the word "optimum" in the title of the thread. :thumbup:


----------



## tfifeco (Aug 4, 2014)

Just dropped car off at the alignment shop... Literally just got back

Going with these settings... or as close to them as he can get

Front
zero toe
-2.5 to -3.0 camber
Maximum caster you can afford (your plates dependently adjusts both parameters).

Rear
1/16" toe in
-1.5 camber


----------



## Marcus_Aurelius (Mar 1, 2012)

^^ :thumbup::thumbup:


----------



## deltaP (Jul 26, 2011)

I found it-:beer:


----------



## TheDeckMan (Sep 26, 2004)

deltaP said:


> I found it-:beer:


:thumbup:


----------

