autoxgt

Just got back from the alignment shop.
The initial measurements were taken with the car empty with 32 psi cold in each tire and 1/4 tank of fuel.
The final measurements were taken with the same tire pressure and fuel but with me in the car (251 lbs).
We played around with the adjustments to see what we could get and basically the rear camber is full out (+) and the front camber is full in (-). We backed out some caster to gain an extra -0.15 in front camber.
Hopefully this will reduce the ridiculous amount of under-steer I had before. The shop that did the alignment is just a tire shop so they usually just align within factory specs. The guy was surprised at how much the settings changed with me in the car.

autoxgt

There is some rear toe but not much. The original was +.28 and the current is +.17.

I couldn't decide if it was worth the extra camber in the front or the extra caster. I contemplated going to +5.0 caster to see if I could get to -1.5+ camber. I was also on the fence about the amount of rear toe since the minimum camber adjustment is still -0.5 over the fronts.

I can bring it back any time in the next 30 days to adjust it if I'm not completely happy with it. I have a local event on 12/8 so I will see if how it works for me. Considering the bump in front camber, it should be more neutral than it was before.

I plan on taking it to a proper suspension guy once I get the coilovers on it. I just wanted an immediate fix to my under-steer until then.

TeamRX8

iTrader: (25)

sorry my bad, that had rear alignment ahead of front alignment so I was looking at the wrong axle end

40w8

Autoxgt,

You got a not bad stock alignment, and it'll still understeer.

Those shops usually don't let you interact, but with that final front right camber of -1.45, and initial left rear of -1.45 which I would have left, and matched the right rear to that -1.45.

My 8 has those 3 at -1.65 deg and it corners on rails without snapping into oversteer.

Our car has very good suspension, and the long length of wheel base helps keep the car running straight (understeer).

That's why short SUV's are so good at turning (flipping). I always buy a long wheel base car or PU, and sort the handling later.

40w8

My alignment tech guy couldn't get rear camber lower than -1.65 on one so I had him put the other one the same.

autoxgt

That's kind of what happened to me. The settings attainable form side to side didn't match at all so we maxed out one corner than matched the other.
The rear corner that started at -2.0 wouldn't go lower than -1.78.
The left front wouldn't go above -1.17 with anything above +6.0 caster.
I tried talking the guy into releasing the preload on the front and rear control arm bushings and shaking the car around to see if we could get more neutral camber setting front to rear.
We were at just -1.22/-1.23 @ +5.85 caster with 0.01+/- toe on the fronts and -1.78 with +0.20 toe on the rears until I sat in the car.
The camber and toe jumped once loaded.
The RF went to -0.81 with -.04 toe and the LF went to -1.72 with +.06 toe.
The RR went to -1.54 with +.03 toe and the LR went to -1.99 with +.17 toe.
I may be a little off on the numbers because I didn't record them but the tech said "Holy cow...Maybe we aught to set it up with you in the car." So we did and that changed the attainable settings again.

The tech at the tire shop is not a suspension guy and is used to matching setting to the factory recommendations with an empty car.
The car definitely "feels" better and I can tell that the rear is rotating easier compared to how it used to "feel".

I know it will still under-steer but 4-6 psi difference in tire pressure front to rear should balance out the grip.

Unfortunately we didn't check the initial settings with me in the car to see where they were at under load.

40w8

Everytime I go to the track my decision on psi changes; just like it should.

When my tire was new and soft 46 hot front and 43 hot rear seemed to be just right, and I got scrub right up to the tip of arrows in front, and barely in back.

Next track day I'd try to recreate that since I don't keep changing parts, and I finally decided that I like all four tires the same pressure.

The funny thing is that the 3 less in rear seemed to make it understeer which I didn't expect.

40w8

The suspension camber changes a lot when the suspension flexes so I don't know if sitting in the car helps even though I did.

You can make it give the better # while you're in the car, but when you're out and it's checked again it'll be lower.

The main thing is: I turned down the rear neg camber as much as it would go, and turned up the front neg camber as much as it would go, so I got all I could for a $130. alignment and quit.

autoxgt

I would think that a higher psi bias to the rear would induce more over-steer and more bias to the front would induce under-steer once the tires are brought out of optimal temp range or pushed at the limit of grip.
That is why I was running 10-12 psi higher in the rear with the old alignment, which seemed to work.
I don't get to build much temp in the tires since we run for about 2 minutes on a tight autoX course on asphalt at night besides the fact that they are 300 treadwear street tires.
I will probably have 5-6 sessions on 12/8 so I should be able to find a decent tire pressure balance.

TeamRX8

iTrader: (25)

The key to high front camber settings on the front with a stock suspension is to put the front up on jack stands, loosen all of the front control arm mounting bolts, unhook the front sway bar, use a jack to heavily pre-load the suspension as much as possible, then super tighten the control arm bolts back up. Do each side one at a time, then hook the front bar back after both sides are done.

You can do the opposite in the rear to get less camber. The amount of preload you do or don't use allows you to fine tuneit as may be necessary within the extreme limits that can be obtained, in addition to setting chassis rake.


.

autoxgt

I figured the factory bushings had something to do with the variance in attainable settings between cars.
The guy looked at me funny when I suggested releasing the bushing pre-load to see if it would change anything. I don't think it was because he was busy either. (I was the only car there)
He also gave me a weird look when I talked about off-set bushings in the fronts to gain camber.

40w8

^So I read your 24f 36r psi wrong, but anyone running that isn't any where near fine tuning with air. That kind of air setup would work on a rear heavy car like a Porsche 911, etc.

Our 8 seems to like close to the same camber all around, and the midrange adjustment of camber gives 1+ deg more in the rears for spin out protection.

When I autocrossed a 73 RX3, I would set the tires after a run at about 44f, and same or 42 -40 rear.

autoxgt

I wasn't fine tuning. I was making a major gap to correct a major imbalance while at the track.
Now that the camber is closer, I will have to fine tune the air pressures to get it where I want it.

EricB

iTrader: (7)

Ive looked through the past few pages and cant make sense of what a good setting is to go with.

Its hugely car dependent, but what is a good baseline to start with?/ try to get as close as possible to?
90% daily,9%mountain driving, 1% autox
Im not concerned with increased tire wear. I havnt gotten an alignment since i dropped my car on the sprints and my camber is all wonky..
Id personally like a safer setup so I dont start sliding. I havnt had enough seat time to perfect a controllable slide.

The place near me will just input stock values unless i tell them what to shoot for.

40th anny Bilstein shocks
Sprint springs Front drop 2"Front rate 187 - 202 lb Rear Drop 2"Rear rate 135 - 147 lb
all other suspension pieces are oem

I do however have 25mm spacers.

There is limitations on how little camber angle i can get due to rubbing. But ill go as close as possible without having issues.

Thanks guys!

autoxgt

The closer you're front and rear camber are to each other, the more balanced the grip will be until you exceed the tires limits.

More (negative) rear camber and the car will tend to understeer (push)

More (negative) front camber and the car will tend to oversteer (drift)

Front caster (positive) will affect the tires natural ability to stay strait. Return to center after a turn and maintain center at speed. Front caster adjustments will affect front camber settings. More (positive) caster =Less (negative) camber.

Toe out (negative) affects turn-in response while toe in (positive) affects stability.

The factory settings have a huge bias toward rear end stability (safe). For my '06 the recommended settings call for:

Front:
Camber -0.10 +/- 1.0 so anywhere from +0.9 to -1.10
Caster +6.47 +/- 1.0 so anywhere from +7.47 to +5.47
Total toe +0.18 +/- 0.35 so anywhere from +0.53 to -0.17

Rear:
Camber -1.40 +/- 1.0 so anywhere from -0.4 to -2.4
Total toe +0.27 +/- 0.33 so anywhere from +0.6 to -.06

There is a wide variance between cars. I suspect it has to do with factory tolerance stacking and maybe bushing/mount pre-load as well as ball joint/tie rod misalignments.

When I did my alignment on my completely stock car, I had the tech pull the rears out as far as he could (less negative) to a matched setting and push the fronts in as far as he could (more negative) to a matched setting. I had him back off the caster (less positive) to gain some extra camber in the front. I had him 0 the toe in the front and leave a slight toe in (positive) the rear.

What I ended up with is:

Front:
Camber -1.35
Caster +5.50
Toe 0.0

Rear:
Camber -1.85
Toe +.17

I will probably take it back in and remove a little more front caster (less positive) to +5.0 to see if I can gain a little more (negative) front camber.
I am also going to add a little more toe in (positive) in the rear to near factory +.25

You're car being lowered will probably run closer to -2.0 camber in the front and -2.5 in the rear. Since our cars have a near 50/50 weight balance I would try to even that out first front to rear.

Pull the rears out (less negative) and push the fronts in (more negative) and see where the balance is. The stickier the tire you have the more camber (negative) they will like when driven hard.

More caster will help the car track strait so as much as you can keep when you set the camber the better it will be. +5.0 may be the lowest you want to go.

0.0 to +0.2 (in) Toe in the front is better for street cars. Toe out in the front is great for autocross but it can cause the car to wander when driving on the highway.

+0.15 to +0.25 (in) toe in the rear will stabilize the rear but too much can chew up you're tires.

EricB

iTrader: (7)

^

so you suggest shooting as close to

Front:
Camber: -2
Caster: +5.0 caster
Toe: 0.0

Rear:
Camber: -2.5
Toe: +.17

I dont mind my tires getting worn. They are shitty all seasons right now but i plan on upgrading to some nice summers. star specs or re-11s.

this will be more of a oversteer setup more than a understeer setup correct? my driver mod isnt that high when it comes to sliding.

dannobre

iTrader: (3)

Why all the camber in the rear?

If you are going to run -2 in the front I would stick to -1.5 to -1.75 in the rear...zero toe in the front, and slight toe in in the rear. Try to max the caster with that camber in the front

Street driving it will wear inside..and on the track the outsides will wear ..so not too bad overall.

If the rear camber is -.5 or more above the front I found it will tend to oversteer more than I liked.

I am running -3 in the front and -2.25 in the rear..zero toe in the front and small toe in ( can't remember??" 3/32 I think)

autoxgt

Yes. With less front camber than the rear, you will understeer. Front will loose grip before rear if pushed past the limit.

The factory calls for over 1* more camber in the rear than the front.
I'm about .45* more (negative) in the rear and the car still understeers when I autocross it. I have 300 treadwear summer tires and a little more front camber would be nice but its what I got for a cheap alignment.

If you can, see if the shop will set the alignment with you in the car since the weight bias side to side will effect you're settings if they set it empty vs you in the car. I'm 250lbs so it was a pretty big shift once I got in.

EricB

iTrader: (7)

Okay will do, thankyou for the help. That first post explained everything clearly to me.


Because less camber in the rear will cause understeer? Thats easy to correct on track, but on a one lane mountain road, things get scary for me.

I havnt gotten an alignment after dropping my car, but the camber looks insane, not to mention the inside tire wear. Its gotten scary for me before. Id rather not go through with it again.

dannobre

iTrader: (3)

LOL...so you would rather have an oversteering car than a neutral one? I have found that higher rear camber than front biases to oversteer all the time..

And that -.5 or so less in the rear is more neutral.....

Each to his own I guess...but oversteer is easy to induce with driver imputs if you are neutral

And I would rather have a slight push that can be corrected easily..than having the rear come around that isn't

EricB

iTrader: (7)

okay, then

Front:
Camber: -2
Caster: +5.0 caster
Toe: 0.0

Rear:
Camber: -1.75
Toe: +.17

??

btw thanks for helping me.

autoxgt

It is probably more dependant on car mods and tires than anything else. Depending on how close the front and rear spring rates are to each other, how the shocks are valved to deal with the spring rates, how close the car rides to the bump stops, sway bar rates, tire size, tire temp range,ect.

I'm not discounting that driver mod is also a big contributing factor to how the car behaves but once you maximize the car set up, the drivers lack of particular skills will show up quickly.

I know that with -.45* more in the rear than the fronts on my completely stock '06, I have to really get on the power on corner exit to get any kind of oversteer. After my alignment, the car felt easier to turn/rotate but no quite enough to be overly worried about loosing the rear.

With stiffer springs and swaybars the amount of rear camber may be less due to less bodyroll.

EricB

iTrader: (7)

bilstein shocks - stiffer than regular s1 shocks
sprint springs Front drop 2"Front rate 187 - 202 lb Rear Drop 2"Rear rate 135 - 147 lb
(as far as springs go compared to how much they drop, sprints are very soft for how much low i am getting, someone told me 18x8 with a 25mm spacer and 245 tires will rub a little)
oem swaybars
25mm spacers
18x8 wheels
225 all season tires

I might buy a used set of swaybars if some pop up on the forums for a decent price.

autoxgt

The front camber at -2.0 should be fine. Set the caster as high as possible with out loosing camber. +5.5 to +5.75 are with in factory recommendations.

Rear camber at the same -2.0 to -2.3ish should be fine with +.17 to +.20 rear toe.

Going into a turn hot (entry) should allow some understeer to let you know that you are entering to fast. Around the apex and exit it should feel like it wants to rotate but unless you are pushing the throttle too hard you should be fine.

autoxgt

A rear swaybar that is stiffer than stock will induce more oversteer by itself. A matched set will keep the car balanced.