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Alignment specs - please critique

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Old 07-01-2010 | 07:44 PM
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Originally Posted by Paul902
Steve, Fly, Adam, yes I'll need to watch the inside rears and consider a tire I can flip. I am currently running PS2s at 39 psi hot. There is so much inside tread left it hurts!

In the end I went with -1.8. front with -0*01' toe (just toed out a touch) and -2.0 rear with KT at 2.5 units. It seems a bit more darty on the street but corners better. I haven't gone hard yet in part because I lowered the car another 10mm and was caught out that the rear M030 end links would not work so I drove home with the rear sway bar in the front...trunk.

Thanks all for the advice and opinions!
Sounds like a good aggressive alignment to me! I also should mention that my viscous coupler is fried so I have a C4S that is RWD which helps give me a better balanced car. You call it darty...I call it lively! That tire pressure seems about right...I've had tires with a stiff sidewall I was able to run 38 hot and then my Hankooks now I have to run 40-42 hot due to rollover. Play with upping the pressure just for fun and chalk the sidewalls to see the difference in rollover. The new alignment will also help. Good luck!
Old 07-01-2010 | 08:36 PM
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Also note that ESPECIALLY on lowered cars, the KT setting is critical to making the car handle well on the track.. A lot of shops say they know how to adjust the KT, but many actually are not experts at it (I don't think the 996 and later cars have the KT setting)..

The alignment guy I used I used actually replaced my rear shocks with dummies (nothing inside and no coil over) just so he could measure the alignment changes of the rear tires under full shock compression and full shock decompression. He then adjusted KT to give the least wheel toe-in/out and camber change over the full motion range of the shock.. It was not cheap, but the car sure handled better after he was done !
Old 07-01-2010 | 10:37 PM
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Originally Posted by flatsixforme
You call it darty...I call it lively! That tire pressure seems about right...
Actually, I like the word lively better than darty to describe it. The ride is just a bit more involving than before. For my pressure, I came to 39 by testing with a pyrometer. Now with the new alignment I'd like to measure it again, but as you say, chalk can tell you a fair amount.
Old 07-01-2010 | 10:41 PM
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Steve, very interesting about the dummy dampers for setting KT. I haven't ever heard anyone do that before. I have no idea what my previous setting was, but I'm curious to see how this setup will feel on the track. Going early August.
Old 07-02-2010 | 02:51 AM
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Originally Posted by Paul902
I am currently running PS2s at 39 psi hot. There is so much inside tread left it hurts!

In the end I went with -1.8. front with -0*01' toe (just toed out a touch) and -2.0 rear with KT at 2.5 units. It seems a bit more darty on the street but corners better. I haven't gone hard yet in part because I lowered the car another 10mm and was caught out that the rear M030 end links would not work so I drove home with the rear sway bar in the front...trunk.
Paul - nice setup . Going with RS or Tarett rear drop links? If you get the Taretts (very nice), suggest you get the rubber boots for the heim joints. Do you have a pyrometer so you can adjust your hot pressures with your new alignment?

Originally Posted by Paul902
Steve, very interesting about the dummy dampers for setting KT. I haven't ever heard anyone do that before. I have no idea what my previous setting was, but I'm curious to see how this setup will feel on the track. Going early August.
It's called 'mapping' the suspension, certainly more critical in cars that are relatively softly sprung and hence will have more suspension travel.

And yes, please call me Bruce.
Old 07-02-2010 | 10:40 AM
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Originally Posted by jdistefa
Paul - nice setup . Going with RS or Tarett rear drop links? If you get the Taretts (very nice), suggest you get the rubber boots for the heim joints. Do you have a pyrometer so you can adjust your hot pressures with your new alignment?


It's called 'mapping' the suspension, certainly more critical in cars that are relatively softly sprung and hence will have more suspension travel.

And yes, please call me Bruce.
Hello, Mr. Dickinson,

Not sure on the drop links...need to do a bit of research first. Had I realized earlier I would have grabbed your RS links, but c'est la vie.

I had borrowed a probe type pyrometer when I did this for the previous settings. Don't have one myself. A few guys I know have the IR type, but it might be time to invest in a probe unit. My suspension is definitely on the soft side (Row M030) as far as track cars go...
Old 07-02-2010 | 12:32 PM
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On the track, the pyrometer will likely tell you that you should have more camber than the stock suspension set-up will allow.. But for a combination street/track car, that is a compromise guys like us with dual purpose cars have to make... I did not want to install camber plates and run > - 2 degrees due to my street use and associated tire wear issues.
Old 07-02-2010 | 01:07 PM
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Originally Posted by Paul902
I am currently running PS2s at 39 psi hot. There is so much inside tread left it hurts!
That's interesting. I'm running between 35 and 36 hot on all four corners and my wear has been good. Granted, my camber settings are only slightly on the side of "aggressive" but that pressure put's my wear right at the marks on 285's and 225's (or 235's) almost regardless of brand.
Old 07-10-2010 | 10:30 AM
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I think 2.8 front and 2.4 rear camber should do the trick. All you need is a set of JRZ and some monoballs and you should be ready to go.

Tire wear isn't really an issue, you should be looking at heat cycles

You need to keep up with the Jonses right? :P
Old 07-10-2010 | 03:14 PM
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The jonses in my neighbourhood are a tough bunch to keep up with!




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