I went from a 16 inch to 17 inch rim and replaced a couple parts (tie rod). I had the car aligned to Pettits street specs and the car was "squirrly". I then took it back and had the setting set to close to stock but I believe the fellow doing the alignment changed the stock settings a bit...Still squirrly but not as bad. When I look at the car it appears to have a little bit on negative camber in the front.

I have the print out somewhere, I'll find it and print the specs.

Suggestions on alignment ?

Thanks.

 

Do you want performance or stability? All performance alignments I've driven are at least a little squirrely on the highway. The exception is a lot of toe-in or toe-out, where the scrubbing on the front tires tends to stabilize things a bit, but obviously that's not a good street setup.

The stock specs have negative camber front and back. IMHO, I think the Pettit short track setup is good for the street, or something bewteen that and stock recommendations.

Dave

 

Toe out = squirrely

Toe in = stability

A lot of either one will wear the tires quickly.

-Max

 

Chris, you need to find a performance shop that is used to setting up track cars to truly get a good alignment these days....if they don't regularly work with custom alignments and sports cars, and don't have a Hunter laser system....move on to somewhere else.

It does indeed sound like there is more toe-out than you are used to. Did they give you a print-out showing the final settings? If not, see my comments above.

 

I took it to a local high end tire/wheel shop that has a state of the art Hunter laser system. We set the car up with Pettits street spec's and the car was all over the road. I took it back and we tried different settings and it's still not right. I have 300 bucks in the alignment so far from the two trips which would be fine if the car was tracking correctly which it isn't.

I wiil find the print out and post it shortly.

 

It wanders with the shape of the a bit road and pulls the steering wheel a little, not bad but doesn't track like it should.

 

Chris, some of that hunt/seek comes with wider, lower-aspect ratio tires.... but too little caster, too much camber, or too little toe might all contribute.

What size/brand fronts did you put on?

 

Peter,
The fronts are 245/40/17's Goodyear Eagle F1 GSD3's.

I found the alignment sheet. It won't upload for me...If someone wants I can e-mail it to them???

 

Shoot it to me, though I don't know how much I can help if it's within the "normal" range. Could be the particular brand of tire (the size isn't too extreme), or maybe a bad bushing?

ptrhahn@yahoo.com

 

Nah, the bushings are perfect. The tire is also run by others I know and they have no problems.

Maybe you could post the specs ????

 

What was the caster set to? I'm running 7 degrees on this car and it feels more squirrely than on my last FD running 6 degrees.

On this car I'm also running more negative camber than I prefer. I'm running -1.4 up front and -1.2 in the rear. Car feels squirrely but I think that this is due more to the caster than the camber for me.

 

Here you go chris:

 

Thanks Peter.

 

I see almost no camber up front and toe-out at both front and rear. That is why the car is squirrelly.

Those settings are set toward understeer. I would bump the front camber up to at least -1 deg, put a little toe-in up front and rear (1/16" to 1/8", or 0.06 to 0.125). The toe should change your steering feel a bit.

 

Tyler,
Are the setting posted close to stock? Also, are the settings you suggest close to Pettit's street specs?

Thanks.

 

Chris,

I believe stock is 0 deg camber front, -1 deg rear with +/- zero toe.

Any kind of positive toe like what you are showing will make the car very twitchy on rutted roads and, IMO, is not acceptable for a non-dedicated track/auto-x car.

For a street driven FD, I strongly recommend something like the following (front/rear):

camber: -1 to -1.5/-0.5 to -1
caster: 6-7 deg
toe: -1/16" to -1/8" front and rear (toe-in)
thrust angle (rear): 0

These values come from the experience of myself and others, as well as from Pettit's Long Track settings.

 

Most alignment shops show toe in as a positive value on their readouts. Typically if the toe value is greater than zero (green) then you in fact have toe in.

They do this because when sane people talk about toe they always mean zero or less. Only the nutball race people ever run toe out

I'd make a quick call to the shop to verify this though.

Any car with wide low profile tires on the front will hunt. Any negative camber in the front makes it worse. Any toe out on top of that make it much worse. My car has negative 2 degrees of camber in the front and 1/16" of toe out. When braking hard I find every rut in the pavement

 

Well, that's a damn good point Damon. I didn't think of that....maybe my getting older brain just crossed wires and he actually has toe-in.....well, back to the drawing board.

 

Whether or not they are using a Hunter Laser machine is irrelivant. It is the person doing the alignment that makes it good.

The best alignment person in our state still uses measuring sticks and bubble guages.

 

Toe out on the rear, i hope not,
While a proper alignment (and person) is critical you might also consider having a set of toe plates, after you get the car where you feel its good you can lean the plates on and do a quick home/track verifiable checkup, if you bump something (or get bumped?) it gives you data for a quick checkup. Well worth the $70.+- for a pair.....not surprising but they seem to always be quite acurate with the shop printouts when we do our baseline readings......

 

Your tire and wheel selection has a huge effect on how the car tracks on public roads because of "sideslip". This is the natural tendancy of the tire to pull one way or the other and is agravated by rutts or grooves in the road surface. My fd would pull from side to side (hunt) when I was on the brakes unless the road was very smooth. The more agressive your tire selection is the more this will be a problem.
As far as the alignment goes there is a big difference between "track" settings and "street" settings. For the street I set my car up with :

camber frt. 0.00 to +.3 deg
rear -.5 to -.75 deg

Caster +6.5 deg

Toe frt. + .06 deg
rear +.20 deg
These settings will help make the car more stable without wearing the tires off. For a mostly street driven car the front camber and rear toe have the most effect on how stable it feels. Also, if you have lowered the car you may have bumpsteer problems. A set of adjustable outer tie rod ends can help correct this.