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kqw kqw is offline
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Factory Ride Height

I know many folks adjust ride height lower than factory spec's.

I had an alignment done recently and it was done correctly but; I now have more bump steer than I want.

The wife and I took a weekend trip up to Boston from Philadelphia and unless the road was smooth, I noticed bump steer from every rut in the road.

I do not want to get a bump steer kit to off set this action.

What EXACTLY is the factory ride height setting?

Thanks in advance....
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Last edited by kqw; 09-09-2004 at 06:39 AM..
Old 09-07-2004, 07:09 AM
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A search on 'ride AND height' will answer your question in no time. Your car is definiteley too high in the pic

Here's a pic to tempt you to go lower and fit a bump steer kit...
Old 09-07-2004, 08:30 AM
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The factory method for determining ride height compares the centerline of various suspension components. As a simplification, most use a ground-to-fender-lip measurement of 25.5" front, 25" rear ( the cutouts are different causing a bigger number for the front).

Wil
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Old 09-08-2004, 05:49 AM
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Thanks Will.
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Old 09-08-2004, 06:32 AM
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Re: Factory Ride Height

Quote:
Originally posted by kqw
I do not want to get a bump steer kit to off set this action.

What EXACTLY is the factory ride height setting?

are your tie rods parallel to the ground ?
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Old 09-08-2004, 06:34 AM
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Ronin..

No they are not thus the cause of the bump steer.

Thanks,
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Old 09-08-2004, 06:44 AM
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What are your reasons for not fitting the bump steer kit...best mod I ever did.
Old 09-08-2004, 06:47 AM
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Quote:
Originally posted by kqw


No they are not thus the cause of the bump steer.

then I figure you'll have to adjust ride height to get the rods parallel. You may also want to check if the rods are equal length on both sides. Un-equal will increase distortion.
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Old 09-08-2004, 07:02 AM
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Measure from the driveway up through the center of the wheel to where it touches the lip of the arch.

What is your current height?

What are your current tire & wheel sizes?
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Old 09-08-2004, 07:04 AM
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Current ride height: Front is 26" and the Rear is 25"

Tires:

205x55x16 Front

225x50x16 Rear

Tire pressure is at 33 F, 36 R

Thanks,
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Old 09-08-2004, 07:15 AM
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kqw,

I like these cars when the rear lip is @ the ht of the rear wheel, and then the nose is just slightly pointing down (about 1 degree).

Your rear tires are 24.9 " in dia, so I would go w/ Wil's suggestion, which is what I have on my car @ 25 1/2F, 25R.
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Old 09-08-2004, 08:19 AM
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Thanks Paul..

If set at 25.5f and 25r, will that eliminate the bump steer?

Thanks
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Old 09-08-2004, 08:30 AM
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If you set your car correctly at euro height, you should have little or no bump steer. The fender to the floor measurement is quite inaccurate though, so maybe do a search on the board for the proper way to measure it. You can also easily check that your tie rods are level.

Eddie
Old 09-08-2004, 08:52 AM
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FYI, the term "bump steer" is often confused with "I feel more bumps when I steer". Not so. Real bump steer is the term for excessive toe change as the suspension travels through the jounce and rebound range (wheel goes up and down). The car handles poorly (or at least not optimally) if you have this condition. It's caused by excessive low (or high) ride height without adequate compensation to the geometry.

Sherwood
Old 09-08-2004, 09:15 AM
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Quote:
Originally posted by kqw
Current ride height: Front is 26" and the Rear is 25"

Tires:

205x55x16 Front

225x50x16 Rear

Tire pressure is at 33 F, 36 R

Thanks,
You should not have steering geometry problems at these heights, but the front should be ~1/2" lower for proper (factory) rake/aerodynamics of the body.

Why do you have so much air in your front tires? That can't be helping the ride. You have stock tire sizes, use stock pressure on the street. 29F/34R. (Look at the sticker in your door jam).
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Old 09-08-2004, 09:58 AM
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Two things:
It should be a simple enough matter to re-adjust the front height. The screw is vertically mounted on the rear-most suspension pivot of the front suspension.....one full turn counter-clockwise ( worm's eye view) will lower the car 1/4". As you lower, toe will, I believe, get more positive....but for the amount you're adjusting, might not need to be readjusted.

At Euro ride height, you won't need bump steer rack spacers. They are only 12-13 mm thick, so if you lower by 12-13mm, that's all these are good for. most people , when they lower, go down more than that and theoretically would require fatter rack spacers...but they don't fit.

I was corrected by Chuck Mooreland that the tie rods being parallel to the ground is not the target.....it's being parallel to the lower control arm. Most of us ( me!) got confused over this because the lower control arm often is set parallel to ground, therefore a target of the tie-rods being parallel to ground seems proper...but for the wrong reason. Upshot? If your lower A-arm is slightly "down" towad the ball joint...better if you set the tie rod to same angle....but then not parallel to ground. Finally, NEVER set the lower control arm so that the inboard pivot point is lower than the outboard ( balljoint end) pivot point....if so you've gone too low...

I guess that's more than two things....

Wil
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Old 09-08-2004, 11:15 AM
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Thanks Dennis...

Re: tire pressure; I haven't run 29psi in front tires since 1987 when the car had Dunlop D40M2's.

But I thank you for the concern. My sticker in the engine compartment says 29F, 36R. Are you sure your's says 34R?

All I want is the car to run like it did BEFORE the alignment.

Will: thanks for the advice on lowering.
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Old 09-08-2004, 03:39 PM
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Let us know how the car feels @ the new height.
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Old 09-08-2004, 03:44 PM
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Paul, will do....

Thanks again folks.....
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Old 09-08-2004, 03:46 PM
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Quote:
Originally posted by Wil Ferch

I was corrected by Chuck Mooreland that the tie rods being parallel to the ground is not the target.....it's being parallel to the lower control arm. Most of us ( me!) got confused over this because the lower control arm often is set parallel to ground, therefore a target of the tie-rods being parallel to ground seems proper...but for the wrong reason. Upshot? If your lower A-arm is slightly "down" towad the ball joint...better if you set the tie rod to same angle....but then not parallel to ground.
ditto
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Old 09-08-2004, 03:49 PM
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