About to get an Alignment, 2nd opinion please?
 

I just put SPL front camber and rear camber/toe arms on my z and need an alignment. I currently have KW v3 at max height with settings all in the middle. Stillen sways, stiff rear middle front. Rears are pilot super sport 325/30/19 front are RS3 245/40/19. quaife torsen LSD.

I'm supercharged at 479hp to the rear wheels and my biggest annoyance is how fast I lose traction when I hit the throttle so I'm hoping to focus my alignment specs on that. I do spirited daily driving and canyon runs, no track time yet.

After research I feel like i should go:
FRONT -1.5 camber 0 toe 5.17 caster
REAR -1.8 camber, 1/32" R+ 1/32" L toe in (so like .01 degree toe in total)

Gomer's suggestions makes me think:
FRONT -2 camber 0 toe 5.17 caster
REAR -1.2 camber, 1/32" R+ 1/32" L toe in (so like .01 degree toe in total)

i THINK this is the best I can do for launch and corner traction without going through tires like crazy. Anyone have suggestions otherwise?

reduce camber
get better tires

Normally I'd ask if you mean go further negative camber but I'm pretty sure you didn't even read what I was asking so I'll wait for another reply.

:iagree: with what he said. Better tires, maybe try playing with your suspension settings to keep the rear end planted?

The numbers in my post are what im CONSIDERING going. Telling me to reduce my camber or play with my suspensions settings MEANS NOTHING because that's what I'm going to do tomorrow when I get an alignment.

I'm here looking for drivers with experience using various camber settings to suggest changes to my proposed starting point.

For instance, is my proposed -1.8 rear camber too negative? Can I get away with -1.2 to get more straight line traction without sacrificing too much grip in the turns since I have a stiff rear sway bar? I don't have experience with this type of suspension modification.

I'd go with at least -2.0° camber upfront, and no more than -1.5° camber in the rear. If you're looking for straight line grip only, I'd go with maybe only -0.5° camber in the rear.

Hmm, definitely not only looking for straight line online grip. But I'll definitely reduce under -1.5.

How bad does -2 camber wear our front tires in this car? Will i be swapping tires from side to side trying to avoid a diag camber wear or will it be fine?

Camber wear on the front is will in some part be dictated by how much aggressive driving they see. If the tires see a lot of hard cornering the camber wear won't be much at all. If they see a lot of highway miles it might be more of an issue. Biggest killer of tires though is poor toe settings.

I'm at 3 rear and 2 front but that's my track setup. I'm s/c too and with Pirelli slicks I still have trouble keeping the back end under it. Coil overs full stiff front and soft on the rears.


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From what everyone has been saying, more camber rear = less traction from acceleration. Have you tried it with less rear? was it worse?

maybe you should read up on how these settings work?

Negative camber generally improves grip while turning

Closer to zero camber is better for straight line acceleration.

No one can give you an exactly perfect setting because you're not driving on some track where there are timed laps to dial it in, you're driving on some randomass road on a personal car

I also find it hilarious that you're trying to get some magic camber setting to help you go faster but also balk at the idea of potential tire wear. Guess what? Hard driving + lots of grip = worn tires. Its sort of just . . . physics? tires are there to grip, the more they grip, the faster they wear. Thats common sense, its why your the prius comes with shitty tires that never wear and last forever but don't do crap for handling, but some spec'd out hardcore racer will have to swap tires frequently

if you want more grip, get better tires
if you think you're losing rear traction in turns, more camber, if you want straight line acceleration, less camber

the factory settings, at least on a nismo, has a bit under 2 deg camber rear and 1 deg front, its not much, but i'm fairly certain they have more camber in rear as a conservative, safety oriented approach.

The track guys can chime in, but i believe when you're trying to go fast you will want more camber in front than rear; the front tires are doing the turning/steering and you want the front tires to have as much grip as possible while turning to dial out understeer. Pretty much everyone tracking their Z is trying to reduce this car's understeer (bigass rear bar, more tire up front, etc)

for you, not tracking the car but with massively increased power . . . again. Get better tires. PS2 Cups or somethin.

You seem like a very angry person. So much written here with so little actual information. You seem so intently focused on bashing my request for help that you can't even read through the entire request and respond in an applicable manner. What are you doing on a site intended to help users help each other?

Speaking of toe settings, what are yours?

You have to consider the difference between street and track. At -2 my front tires wear even across the tire during heavy cornering and the setup for my car does the same on the rears at -3. At less than that, my tires wear severely on the outside edge. I'm running ksport coilovers so my car may roll differently than yours or anyone else's since it's half Nismo and half aftermarket. You just have to monitor your tires and the seat of your pants to find your happy dance. I think your original post is a good starting point for your driving habits. My two cents and happy driving to everyone!


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If I remember correctly, front toe is 1/16" out and rear is 1/16" in. fwiw mine is primarily an autox car where cornering grip is everything.

I'm guessing you have either way too much spring in the rear or too stiff of a sway bar in the rear or both. If you need -3° in the rear you have something else way out of whack. Our cars have a lot of dynamic camber gain in the rear so therefore a little negative camber goes a long way.

Stock Nismo sway bar and on coilovers so stock springs have been removed. She's been lowered at least an inch and a half also. Tire wear and lap times show it's where it needs to be, so like I said, everyone will be different.



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If you're still using the factory sway bars that's your issue. Put the stiffest front bar on (Hotchkis) and the softest rear bar (might also try no rear bar).

I think you have some mis-matched expectations here .............

480whp is a tough ask for any rubber ........... and there are a bunch of compromises to consider.

By standing the rear tyre up (less camber) you flatten the tread face to maximise grip potential, BUT the torque associated with 480rwhp is going to torture the tyre in lower gears (remember, a gearbox is a torque multiplier in lower gears ....).

When you launch the car, it will squat at the rear which induces more camber which lessens the size of the contact patch .........

BUT

when you tip it into a corner, the car rolls and you need some rear camber to ensure that the car does not fall-over on the outside tyre and reduce the contact patch size because the inside of the outside rear tyre becomes unweighted ...

So, before being prescriptive, consider whether you are asking seeking a unicorn ..... because the best solution might be to feather the throttle in low gears .... laying two black lines all the time becomes expensive in the end.

Rather than thinking that suspension alignment is the "fix", you need to re-think objectives because some solutions - like standing the rear tyres up some more - actually hurt other areas - like cornering grip.

The answer will be a combination because it is a system fix .... and by that I mean
1. Alignment to OEM specs as a starter so the car will still corner (maybe go "more" neg at the front to promote healthy turn-in
2. Sticky tyres that you replace regularly (rear at least)
3. Moderate your throttle inputs at low speeds/gears (or invest in an aftermarket Traction Control system which aligns torque to available grip)
4. Think about softening the rear in roll (no or softer rear bar) and giving the car a little less bump stiffness on the rear shocks to promote compliance to improve grip and a bit less rebound at the front to let more weight transfer to the rear. This is a dark art and depends on adjustable shocks. You "could" also look at less rear spring as a stiff rear spring does not promote rear grip

For point 4, you need to test and if this is not something you are comfortable doing, then an aftermarket TC system is the best option.

I was thinking about dropping one end of the rear sway bar next event just to see if she would keep all those horses from spinning the tires. I'll post the results.


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These are great points. I understood from the start that it would be a balance not the best of both worlds. The traction will definitely be improved by all the work i already did (lsd, whiteline bushings, spl camper and toe arms with solid bushings) so a moderate amount of camber should be fine in the rear. I'm gonna have to go back to softer on the rear stillen bar, i just changed it.

So after agonizing over different opinions I decided to pick some numbers that went along the middle of what everyone suggested.

Front: -2 Camber, 5 Caster, 0 Toe
Rear: -1.5 Camber, 1/16" total toe in (.134 degrees total toe in)

That's at least the specs I gave my alignment guy. This is what I got back as the best he could do: Alignment Printout

Transcript of what I ended up with:
Front: -1.7|-1.8 camber, 5|4.8 caster, .1|.08 degrees toe in (.18 degrees total toe in)
Rear: -1.9|-2 camber, .22|.28 degrees toe in (1/2" or .5 degrees total toe in)

Lots of excuses about not being able to get toe exactly where i want, i guess I need to do toe bolts front and back because even with SPL fuca, rear camber and rear traction arms I still somehow don't have enough adjust-ability.

Most notable is that the toe in in the rear is .5 degrees, which this calculator says is 1/2" total toe in? That's WAY too much right? That's even with .5 more negative camber than i wanted there too. My front is 3/32" in total as well when I wanted 0. This is frustrating after $1200 in SPL parts.

If you got the titanium fully adjustable rear traction, camber and toe arms, there is no reason why the 'alignment' guy could not have set everything to your spec. My question would be, is this a 'reputable' shop and does the 'alignment' guy know what he is doing? :stirthepot:


IMHO, I'd take it to someone else. SPL says their stuff is designed to give maximum adjustability for vehicles using what you have for coil overs. It appears that the shop you took it to was too lazy to do the job right. :twocents:

For the rear I only have the "camber" and "traction" arms as the toe arms said they're for if you go true coilover setup.. I figured since i could dial in camber anywhere i want with the arms the stock toe bolts would be good enough, sigh. In fact I'm pretty sure i still have SPC toe bolts in my garage i just didnt install them because i didn't think i'd need them.

The shop guys is pretty decent, but I wouldn't call him a master by any means. He's just the only shop close to me that can get my car on his alignment lift. everyone has too big a ramp going up and will rip my low Stillen front bumper off.

Wait if toe bolts only adjust 1 more degree of toe (which means only .5 degrees more out) That shouldn't really make a difference in getting me back towards 0 toe right? Naturally the car at stock camber should be able to go either toe in or toe out quite a bit so If im right in the middle of rear camber spec i should be able to easily hit toe spec.

**** i hate dealing with other mechanics. I wish i could do my alignment myself.