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Wheel alignment, settings, problems and questions :)

Old 07-19-04, 04:45 AM
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Wheel alignment, settings, problems and questions :)

I wanted to get my car aligned before heading out to the track again yesterday (hey, its always nice to improve on your previous best time )

I wanted to set it up with a bit toe-in front and rear and -1.5 camber front and -1.3 camber rear.

When we got to measure the alignment (without me in the car) I saw the following:

- front toe is ok
- front camber is POSITIVE !! (probably settles into 0 with me in the car)
- rear camber is negative, around -1deg or less on both corners
- rear right toe is positive (probably due to bad right toe-link)
- rear left toe is negative

Due to rusted alignment screws in the front we aborted the alignment, and I will need to take my car to the mechanic so he can heat those screws up and loosen them.

Now I'm asking is -1.5fr and -1.3rr a good camber setting for track use ?

Another question - what problems are caused with messed like suspension settings like I have ?

Thing is that my car really feels nervous in some corners and has tendency to oversteer. Can this maybe be cured a bit with front strut brace ?

But on the other hand - if I manage to sort my camber in front, I will get more grip in front and car will have tendency to oversteer even more, no ?

I was running 35psi hot on front tires and 30psi hot in rear tires 225/50/16, stock suspension.
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Old 07-19-04, 09:04 AM
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if you want to go fast and have a car that is easy to drive on the limit you will need to start a process rather than find one magic suspension setting. i raced for 22 seasons and am familiar w the process...

buy a pyrometer. you can find an adequete one for around $100. optimized track settings don't work really well on the street... (generally too much camber) a pyrometer will tell you what camber you need and air pressure too.

BTW, 30 hot front and 28 hot rear is about right. i have posted lots on the subject in the suspension forum so just search thru my posts and good luck.

as to settings..... a nice start for the street and track is 1.2 degrees neg camber fr and rear. less than an 1/8th toe in front and rear. w the above tire pressures. adjust trim w tire pressure.

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Old 07-19-04, 09:19 AM
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Smile



I like the Pettit Long Track specs. They work well for the street and track (which is about what you are trying to set). Then, when you get some stiffer springs you'll be all set!
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Old 07-19-04, 11:06 AM
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Yes Mahjik, Pettit Long Track specs look like a nice starting point.

My car feels nervous at the limit and doesnt give me the confidence I need.
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Old 07-19-04, 11:11 AM
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Howard - those hot tire pressures would be even lower then what I use on the street and would make me ride on my tires sidewalls through turns. Why would you suggest such low pressures on stock 225/50/16 tyre ?
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Old 07-19-04, 11:27 AM
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Originally Posted by cruiser
Howard - those hot tire pressures would be even lower then what I use on the street and would make me ride on my tires sidewalls through turns. Why would you suggest such low pressures on stock 225/50/16 tyre ?
What kind of tires are you currently using?
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Old 07-19-04, 12:05 PM
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Still on the 3years old Dunlop SP9000. Normal high performance street tires.
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Old 07-19-04, 12:55 PM
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Originally Posted by cruiser
Still on the 3years old Dunlop SP9000. Normal high performance street tires.
Well, IMO, it sounds like you are trying to solve a different problem than just what your alignment will solve. Howard has MUCH more experience than I do, so hopefully he'll jump in.

The tire pressures seem a little high for me. I used to run the street tires about 32 hot. I never tracked my car without having a front strut tower brace or on the stock springs so I can't compare the stock equipment with the aftermarket stuff. However, being were I am now; if I were you, here's what I would do:

1. Get the alignment set with the Pettit Long track specs
2. Upgrade the springs to something like the Eibachs or RSR Race Springs
3. Purchase a used set of stock rims and throw some VictoRacers on them

I'm sure a front strut bar helps some, but I'm not sure to what degree you'll see the improvement. The other 3 things above would probably make a better improvment to your car than the strut bar right now.
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Old 07-19-04, 01:33 PM
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I have the front strut bar, I must've badly expressed myself in previous post. I just wonder if stock strut bar is adjustable in any way and if it brings anything to handling ?

Btw. what about H&R springs ? They are progressive, right ?
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Old 07-19-04, 01:54 PM
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good beginning track susp setup for stock size wheels and tires. -1.5 camber front with a little toe, +6 caster or as much as you can get evenly on both sides, -.05 rear camber and neutral toe. Front tires will of course wear a bit on the inside during normal street driving.

I like to see pressures come up to about 42 to 44lbs when hot or I just rip the tires to pieces especially if they are street tires. I would start at about 30lbs on a hot day and see where they go and check the wear pattern when you come in. Tire pressure will very with the type of tires and alignment you have.
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Old 07-19-04, 02:01 PM
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Cruiser,

I got my car aligned last week. It was probably in a similar state as yours. I now have something close to the Pettit long track specs. I have not had a lot of time in the car yet, but my first impression is that the car is much more "tossable". By that, I mean that the car seems to flow better from one turn to the next. It just seems a little more user friendly. Howards air pressures sound a little low to me, but I am willing to try them at my next event. I am currently running Bridgestone 750's in a 245/45 size on stock rims. I ran 35/33 psi at the last event (autocross), and was thinking it was too high. I had a serious understeer problem.
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Old 07-19-04, 07:02 PM
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Originally Posted by cruiser
- rear right toe is positive (probably due to bad right toe-link)
This will cause oversteer on left-hand corners.
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Old 07-20-04, 01:00 AM
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Originally Posted by Eagle7
This will cause oversteer on left-hand corners.
And this is a track with mostly left-handers. No wonder those M3's were infront, lol

Thanks!
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Old 07-20-04, 05:14 AM
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Ready for takeoff

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Old 07-20-04, 09:39 AM
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Thumbs up

Originally Posted by cruiser
Ready for takeoff

Very nice pic! No helmet?
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Old 07-20-04, 10:52 AM
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No helmets required for now.
And with my height, I doubt I could squeeze one between my head and the roof

I really like the pic also. FD in its natural environment
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Old 08-02-04, 12:16 PM
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Hey fellas,
I have an '85 GSL. Stock 13" wheels with Sumi's 215/50/13. I have the ground control setup.

http://www.ground-control.com/?D=29b...85f81bae188263

Tokico “Illumina 5”,
Springs “Coil-Over kit”, 300/175 lbs./in.
Camber / Caster plates

I also have the bushings and the larger front sway bar.

I do autoxing and tracks when I can afford it. What should I set my camber/caster/toe to? It's also a daily driver so it needs to be safe at interstate speeds. I'm not worried too much about tire wear but needs to be able to handle rain, the interstate and traffic.
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Old 08-02-04, 12:25 PM
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Bob,

Since you have adjustable camber plates, you can easily change your settings at the track. I used to run around 3 degrees neg camber on my FB at autocrosses. I had 225/50/15 R1 tires all the way around (flared fenders) and the car was very low. That worked pretty well for me.
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Old 08-02-04, 12:31 PM
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Adam,
Maybe you can adjust it track side but I can't. I'll end up with +3* on one side and -3* on the other. The toe will be about +12" and -1". And I'm not sure what caster even does.
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Old 08-02-04, 01:19 PM
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Bob,

Of course, adjusting the camber will effect the other adjustments slightly. I suggest that you mark your camber plates for "street" and "race" settings. Use a brightly colored nail polish, or something else that won't come off easily. My camber plates were easily adjustable by jacking up the front of the car. I don't know why yours would be any different.
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Old 08-02-04, 03:42 PM
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Oh, it's not the adjustment that would be difficult. It would be the knucklehead turning the wrench that would be the problem.

Of course setting it up correctly and then marking everything would make it easier!!
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Old 08-02-04, 03:55 PM
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Knuckheads are always a problem. After years of trying, I have been unable to repair mine
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Old 08-02-04, 03:55 PM
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Originally Posted by adam c
Bob,

My camber plates were easily adjustable by jacking up the front of the car. I don't know why yours would be any different.
I'm not sure but I don't think the car would have to be on a jack. It should move fairly easy without. I certainly wouldn't have to lift the car because the springs aren't engaged when the shocks extend. There's literally 4 or 5 inches of travel with the perches turned all the way down and the car on stands.
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Old 08-02-04, 04:47 PM
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You should give it a try. Its not likely that you will be able to move the top of the tower freely without jacking the car up, and taking at least some of the load off the suspension.
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Old 08-03-04, 01:56 PM
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If I use a big enough hammer I shouldn't even have to loosen the bolts.
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