A little help please

[175rgr]

Hello all,

First off let me introduce myself. My name is Drew and I ended up buying an amazing car from an incredible guy here Jason(n77nxc).

I've been trying to chase down an issue with the front suspension and need a little bit of help.

The car has: SPC Upper control arms, CPP Lower Control Arms, Qa1 coilover conversion, DSE front sway bar and CPP C5 Spindles (AFX Copy).

While Jason had the car he was trying to figure out why he was chasing the front end around the road and why it had just horrible play/deadzone in the wheel. It was suggested that he buy a Turn one box but he never got around to doing it before i picked the car up.

I got the Turn one box installed yesterday and while it is 100% better the car still has front suspension issues and likes to behave a little twitchy. I still feel like im chasing the front end around but its just more manageable because of a tighter more precise box.

I had the alignment checked and rechecked, I'm currently running +5 caster, -.25 camber and 1/8th of toe.

The car steers pretty stiff due to the caster but nothing to crazy, it still has some deadzone in the middle of the wheel but not to the point where the box isn't doing any work. I've checked the input/output on the box and they work in conjuction perfectly, much better than the old box which was garbage.

What I have done thus far:

Rechecked all steering and suspension components for play and insured all attachment points are tight and torqued.
Checked each individual wheel for play by itself and checked it for any play through the linkage by watching the other wheel. Everything tight, no play found.

After going through the entire front suspension I could only bring myself to one conclusion. Something in this setup is not working correctly or not working correctly in conjunction with one of the other parts. So....

Does anyone have any ideas on the compatibility with CPP lowers, SCP Uppers and the CPP C5 (AFX) Spindle?

Does anyone have any other idea on what this issue could be?

Forgive me if my explanation is off I'm trying my best to put it into words without someone actually driving the car.

It's basically bump steering itself within the "deadzone" in the middle of the wheel. I can move the wheel ever so slightly going down a perfectly smooth road and the car will ever so slightly turn itself, but at speed the bumpsteer obviously occurs quicker in turn causing me to make bolder adjustments with the wheel. Not sure if that helps out.

I'm on the verge of pulling the trigger on a ridetech front control arm, tru turn, coilover setup, or a speedtech control arm setup or maybe a DSE control arm setup just to get all the parts from one manufacturer that were designed together.

I thought I would ask here for any ideas before I spent a bunch of money I didn't need to.

Thanks in advance.

Respectfully,

Drew

[NvrDun71]

Just a thought but are the springs on the hybrid QA1 coil over's seated correctly in the upper subframe spring pockets? Has a nut and bolt check been done on all front end and steering parts? All steering parts new and in good shape?

[175rgr]

Nut and bolt check has been done. I'll get in there and confirm the springs are seated correctly.

[dhutton]

If it were me I'd get the real AFX spindles. The geometry of those CPP spindles is not the same and I don't think they fix bump steer....

Give Speedtech a call. I am sure they can tell you the differences.

Don

[raustinss]

Try send a pm to Ron Sutton.... He's the man you need

[marolf101x]

Toe in, or toe out. . .you did not say.
Toe out will make it "wander" more.

What size tires?
What brand.
Wider front tires tend to "grab" any rut in the road and follow it.
Different brands cause different issues.

What we really need to know is exaclty when this happens.
If it happens when the car is travelling straight with little to no suspension movement. . .it's likely tires and/or alignment.

If it happens when the car is travelling straight just after hitting a bump. . .it's bumpsteer.

However, there are so many possible root causes it's difficult to say without looking at the vehicle. It could be a steering component, a ball joint, something in the rear end suspension that allows it to move ever so slightly and create rear-steer.

[175rgr]

Thanks for the help thus far!

Tires are:

245/45-18 NT555


It only does it when traveling straight down the road and it doesn't take much of a "bump" could just be a slight change in the road surface from one lane to another to make it move.

If you are familiar with some intersections that have the white "rumble" bars that you drive over to alert you to the traffic intersection, those will take the front of the car and push it left and right as you drive over them.

The qa1 springs are mounted correctly in the upper spring perch.

I'm going back through one final time to torque everything again after that im out of ideas.

[marolf101x]

Generally speaking. . .

if it wanders when going straight, no suspension movement. . .it's alignment, tires, or both

if it wanders when the suspension moves. . .it's a geometry issue.

Bumpsteer is easy to check.
-lift the car off the ground
-remove the shock and spring
-place the suspension back at ride height
-using a toe plate, or anything flat against the rotor, compress the suspension and use a tape measure to measure from the front of one rotor to the fron of the other, then the rear of one to the rear of the other.
-write down both front and rear measurements; subract the two
-ride height is your "Zero" number, deviation from that number is your bumpsteer
It's pretty crude, but it's nearly free and only takes an hour or so.

what rear suspension is under this thing?
have you had it on a 4 wheel alignment rack (with a good alignment guy) to make sure the rear is installed square and true?

[Ben@SpeedTech]

Feel free to call us any time M-F 8:00-5:00 mountain time at 435-628-4300. We're happy to listen and help you work out issues, sometimes harder to do by typing back and forth. We can go over the advantages of the AFX spindle and help determine if it meets your needs as well as discuss possible suspension packages without sales pressure, we're here to help.

[175rgr]

Sorry I haven't been replying very quick things are getting pretty busy at work.


It only wanders under suspension movement.

It has been on a good alignment rack with a good alignment guy, but i did not have him check the rear to make sure it was trued up and all was good.

The rear has hotckis drop springs with koni shocks, nothing special.

If I get a chance in the next few days I'll give you guys at speedtech a call.

I've added a few photos below of where everything sits while it is on the ground, and a shot of the current ride height. If it helps.

Current Ride Height


Passenger Front

Driver Front

Driver Rear

Passenger Rear