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Calling RX7 Carl....

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Old Apr 9, 2005 | 07:13 PM
  #1  
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Calling RX7 Carl....

A while back, you outlined a modification to the rear control arm bushings on a 1st gen to lessen the oversteer problem. I recall it was drilling the stock rubber bushings, then greasing the pivots and using lock nuts, and you were selling the lock nuts.

I need a set.

Also, for autocross, what would you recommend for a front sway bar? Currently I'm using the stock bar with urethane end links and frame bushings. The car will push in very tight low speed turns under any power, and at higher speeds, say coming out of a long sweeper onto a straight, the rear will step out. I am using Energy Suspension urethane bushings on the rear all through, allegedly since they are 'three part' (two soft bushings sandwiching a hard urethane donut) they are supposed to not bind, but I'm having my doubts, hence the request for the lock nuts. I'm running a stock clutch type limited slip and Kumho 205-60-13's on Circle 13x7's with 4" backspacing, 175 inch pound rear and 350 inch pound fronts, Tokico Illuminas full hard in the front and full soft in the rear (that seems to help the oversteer, which is why I'm interested in the front bar and softening up the rear bushings as much as possible) and I have a stock rear sway bar but it's disconnected on one side. I get my best grip with 34 PSI all the way around.

Suspension settings: 3 1/2 degrees negative camber and 4.5 degrees caster with 1/4" toe out in the front (Ground Control's recommendation), I have set the ride height to GC's recommendation but the car's never been cornerweighted (nobody in this pissant burg owns any scales).

TIA.
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Old Apr 9, 2005 | 07:26 PM
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not tryong to be mean, but wouldn't it have been better to just PM him?
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Old Apr 9, 2005 | 10:22 PM
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Yea, but now he can get lots of opinions on his question.
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Old Apr 10, 2005 | 12:30 AM
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LOL

Last edited by diabolical1; Apr 10, 2005 at 12:32 AM.
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Old Apr 10, 2005 | 03:13 PM
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or just visit his website and read the writeup


http://pbandjracing.com/rear_suspension.htm
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Old Apr 10, 2005 | 03:57 PM
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^^ That's what I was looking for! But I still need the locknuts, no one im my town seems to be able to come up with the thread pitch it requires.
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Old Apr 14, 2005 | 08:22 PM
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HI! emailed you about the nuts.

I have no internet at work anymore so my time on the comp is really limited.

As for the tight in condition. What tension rod bushings do you have? If they are harder than stock, I'd reduce your toe-in to 1/8". And are those tire pressures hot? Im not familiar with the Kumhos sorry. You might wanna try dropping the pressure. Whats the recommende pressure for that weight car?

For the loose off. Again, possible too high a tire pressure. Also limited suspension compliance (binding) (from those hard link bushings, especially in the short uppers) will cause that.

If the car is that bad with the sway bar connected, then you probably do have a roll compliance issue with the rear suspension. Is it a "snap oversteer" type of problem? Or is it more progressive?
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Old Apr 26, 2005 | 09:23 AM
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Originally Posted by diabolical1
not tryong to be mean, but wouldn't it have been better to just PM him?
I'm glad he did not. This is good info that I did not even know about.
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