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Raise front end 1/4"...re-alignment?

The car was aligned and corner balanced recently. My ride height is set at:

Front right: 23.75"
Rear right: 23.9"
Front left: 24.2"
Rear left: 24"

It's great for the track but I'm getting tired of dodging road kill or washing fur off my spoiler (so far I haven't created any roadkill but it's just a matter of time)! Some recent post-holloween pumpkin carnage was also removed from my spoiler last week.

Can I dial up my front end "evenly" about 1/4 -1/2" without messing up the alignment? I would dial it back down for track days, etc. I've gotten mixed answers so thought I'd check with you guys.

Thanks for your help,

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Old 11-08-2002, 05:56 AM
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Everything on an alignment is interrelated. You can not drop it down for track days without changing things. Decide what's most important, set it that way and leave it.
Old 11-08-2002, 06:43 AM
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raising the front will increase toe in and reduce negative camber on the front. both of those things could be considered beneficial on the street. I would think only a quarter to half inch difference wouldn't make the change very large. I wouldn't think it would be a problem. Just remember how much you turn the adjustment screws.
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Old 11-08-2002, 07:13 AM
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It will also effect the corner balancing of the car.
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Old 11-08-2002, 07:56 AM
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Yes, it will affect corner balance. My thought is that as long as the two screws in the front are adjusted equally the only change should be to shift a little weight to the back and then if they are adjusted back to the original position for track days they should go back to the original balance.
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Old 11-08-2002, 08:09 AM
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I really like what Steve is saying...by raising the front of the car evenly, I "improve" the alignment characteristics for street driving (while also reducing the threat of damage to my spoiler). For DE, I can simply dial the front end back down the same number of turns to achieve my current track alignment (and corner balance).

This seems to good to be true....
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Old 11-08-2002, 08:25 AM
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Mike,
Correct me if I'm wrong, and please take this as just my opinion, but with those measurements it would appear that your car is sitting too low overall in the front, regardless of use, in relation to the rear ride height.

While measuring from the tips of the fender lips is less than completely accurate given the variations from car to car,(even side to side on the same car) I seem to recall that Bruce Anderson's recs (again, just another opinion...) were that the front ride height should be 1/2" to 3/4" higher in the front than the rear when measured at the fenders in order to give the car a proper (approximately 1 degree?) amount of "nose down" rake. While counterintuitive, this is because the top of the rear fender tips are not parallel to the fronts.

With your measurements, IMO, your car may have too much front rake. I would pick a height that you can live with on the street, corner balance/align and use it for the track as well.

Good luck,
Tim
Old 11-08-2002, 10:02 AM
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Mike;
FYI - It is possible to set McPherson strut suspensions too low, ground clearance aside. The geometry of McPh struts goes into a bad zone if the lower arm is lower on the inside then the outside. Keep in mind that this might happen while under braking and turning into a corner, so ideally you want at a height such that your lower arm is flat or better yet slightly higher on the inside.

If you lower a McPh strut too low, the roll center goes below the track surface which starts to cause some strange jacking affects to happen. You might want to keep this in mind as you set your alignment.
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Last edited by jluetjen; 11-08-2002 at 10:45 AM..
Old 11-08-2002, 10:40 AM
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Cool

I agree with Tim. Go half an inch higher in front vs. rear to get a one degree nose-down attitude. Are those figures with a full tank? What camber do you have in front now? Also, too low in front means possible bottoming out on the struts while cornering
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Last edited by Gunter; 11-08-2002 at 10:49 AM..
Old 11-08-2002, 10:46 AM
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I don't think raising it 1/4 inch would be enough to really affect your alignment much,

but I would think that as soon as you turn one of those screws, your corner balance will be shot.
Old 11-08-2002, 11:12 AM
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Here are my alignment settings:

Rear camber -2.0, -2.0
Rear Toe +.08, +.10

Front camber -1.3, -1.3
Front caster +5.6, +5.6
Front Toe +.11, +.11

This is with a full tank. I've had no bottoming or weird handling problems at all. Hope this helps.

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Old 11-08-2002, 11:57 AM
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