Still having stability issues

shadow85

Been having this issue for a long time.
Car will not track straight when I let go of the steering wheel, it feels like it always wants to pull to one side almost immediately, also sometimes more pronounced when I hit the brakes.

Cannot do hard launches because it almost instantly wants to fly into another direction off the line! Even with only a small amount of hard throttle it can feel like it wants to do that.

This problem only seems to happen randomly, some days the car feel like it will travel straight at cruise speeds and launch straight, some days I have no hope at all.

I have had 2 alighnments done from 2 different alignments centre in the past 6 months. The 2nd one they also installed brand new MCA street Ultimate coilover and set the softest setting on the back before they did the alignment. After I picked the car up from them, everything felt perfect and stable, but only for a few hours of driving which after it went back to crap again. They said they will look at the car again next week.

Just trying to get any opinions if anyone knows what the hell is going on before I take the car back to them.

Could it be something to do with any of my parts not functioning well?
I have added these parts all at the same time:
Z1 urethane motor and trans mounts
Whiteline diff bushin kit
Quaife LSD
Z1 Premium SS brake lines
Could it be that a long time ago my aggressive offset Meister S13P wheels on the front 19x9.5 +17 scraped the Akebono calipers for a little while, could that have done some damage to cause my current issue? Brakes pushing the wheel or something?

I have uploaded the latest alignment sheet.

OptionZero

Just off the bat a caster is over a degree different side to side

I can't remember - did you get the SPL FUCA?

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shadow85

Yes I have SPC front camber kit and eibach rear

2011 Nismo#91

Caster and rear tow setting are off.
Car Suspension Tuning Guide| Rapid-Racer.com..

OptionZero

You didn't read what i wrote

S P L F U C A

Your caster settings are clearly off, they shouldn't be over a degree different side to side. I don't know if something is wrong with your components or if your alignment techs are incompetent but you should talk to them about what there is such a delta between left/right front caster

The SPL Fuca (not the dumbass SPC ones) have a MUCH greater adjustment range with much better components. It is unclear if the components are the issue or your alignment shop but AGAIN, you should ask them about this

if your suspension adjustment in front is already maxed out, you're going to need to upgrade

then again, you should upgrade them anyways

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shadow85

Ok sorry just realised they are different things lol. Yes I have only the SPC front camber arms and eibach rear camber/toe kit.

And I will purchase what ever the hell is required to get this damm issue sorted lol

So if it is reccommended to install the SPL FUCA then I will go ahead and purchase that. So looking at my alignment sheet, is that the reason why my car is acting abnormal when trying to go straight?

Rusty

You have over one degree difference in caster. That will cause a pull. Which way is it pulling?

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Spooler

Yeap, he is toed out in the rear at a -0.1. Have your toe settings set this way. This will cause the car to not track straight when and if you start spinning the rear tires.

Front:
Left: 0.5
Right: 0.5

Rear:
Left: 0.9
Right: 0.9

Spooler

I missed that. Not good either.

cv129

And the tech did not go over the effect of the new alignment with you? The rear toe-out (instead of toe-in) is alarming, that a reasonably knowledgeable technician doesn’t give you any warning at all. Toe-out isn’t for everyone, certainly not the safest thing for a street car.

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Chuck33079

Shadow, I told you months ago you had an alignment that was AFU.


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OptionZero

He was definitely told. Had the same problem the last time he posted about his alignment:
Same issue with the castor

SPL catalog + better alignment tech

Are you going to some generic consumer alignment chain or a shop that actually does custom stuff for sports cars?

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BGTV8

Call Mark Povey at SA MotorSport Tyres (0409 288 380) and ask him for the name of a race alignment shop.

Please stay away from rear tow out - it creates dynamic instability under power and the car can get away from you real quick.

PM me if you want more personal info.

I'm in Vic but I do know a bunch of motorsport people in Adelaide and can connect you to the skills you need.

Eagle

Not all heroes wear capes, i think OptionZero and BGTV8 just saved the day

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redondoaveb

I was just looking at the alignment sheet on my old car and they had my rear toe at 0.15" and front toe at 0.10".

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