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Running a first gen without a sway bar for Time Attack

Old 06-02-08, 09:51 AM
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Running a first gen without a sway bar for Time Attack

I was running time attack and lapping yesteday without a rear sway bar, going by the first gen guys that auto-X most of time, that is makre the car steer better. Was this a wrong approach for a road circuit as it involves higher speed? My problem at the track was I was getting a whole bunch of mixtures of oversteer, understeer happing in the same corners. I know my tire pressure adjustments had probably something to do with that, but what kind of a difference would i be seeing normally by going with a rear bar? A more oversteered prediction?
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Old 06-02-08, 10:59 AM
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The removal of the rear sway bar softens the rear end. This makes the rear end bite much better, especially at higher speeds. The 1st gen without the bar will roll a lot on turn in, take a set and hold until you finish the corner. With the bar mine would start to set, jack a bit, get skittish, then settle, jack, skittish, etc. Basically forced me to correct all through the corner. Keep in mind this is on a Spec 7 class car, with 350 inch-pound springs up front and 175 inch pound springs out back.
Running a bone stock 1st gen we've also pulled the rear bar to get a softer rear with much the same effect. (You can either firm the front or soften the rear for better rear bite.)

To get the car handling as good as possible I'd stiffen the front a bit, put in as much negative camber as I could and go through the watts link making sure it pivots smoothly.

My $0.02

-Trent
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Old 06-02-08, 11:09 AM
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I couldn't reccomend enough to remove the rear sway bar from a 1st gen driven on the track. Very few fast 1st gens use a rear bar, and the addition of a 1 1/8" front bar really helps out.

It's not uncommon to use a rear bar in autocrossing because of all the tight low speed corners and the need to rotate the car so it'll point towards the corner.

Then there's the whole discussion on the rear geometry being all outta wack from the factory...
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Old 06-02-08, 11:37 PM
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I prefer mine with no rear bar. With the bar the car oversteers all over the place.
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Old 06-03-08, 12:28 AM
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When I was running stock suspension, I pulled mine after a snap oversteer incident (later found it was due to low tire pressure in one tire). Running without the rear bar, well I couldn't really tell a difference.

Later, I installed a RB front bar which made a huge difference in the handling and behaviour of the car. After about a month with that, I reinstalled the rear bar. I think that really put the finishing touches on the car. It is very well balanced now, and even if you do get a bit of a slide going it is very controllable.

I now have a Respeed front swaybar, and an ISC Racing adjustable rear bar on the stiffest setting. Very nice!
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Old 06-03-08, 08:11 AM
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Cool, I'm probably going to pick up the RESpeed front bar, not sure what to do about the rear yet. Hopefully Respeed can do a tubular one also.
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Old 06-16-08, 07:01 PM
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I say try it both ways and see what you like instead of doing what others tell you. I personally like it much better with the rear bar, and if you do the math it should handle more predictively with the rear bar installed. With the rear bar it takes more G forces for the car to reach the infinate roll point. yes it might slide around little more, but it greatly reduces SNAP oversteer. I say controlable oversteer is much better than great traction then snap oversteer.
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Old 06-16-08, 10:50 PM
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Alright .. well the bar can go in there fairly easily anyways. I'll take it with me to the track and try it out there. Thanks for all the suggestions though. I want to see how it handles with just the big front bar though.
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Old 06-17-08, 06:41 AM
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As long as you don't get too much understeer with the heavy front bar you should be happy, but if you want a little more ability to kick the back end around then you'll want the rear bar back on. Either way, you're going to see an unbelievable difference with the heavy bar up front. Made my car feel brand new.

I just ran my first race using the Respeed bar up front with the ISC Racing bar in the back (set on the stiffest setting). Pure sex!

Porsches and Miatas hate me.
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Old 06-17-08, 09:17 AM
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Cool, good to know that i'll like my car even more
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