Corner Balance / Ride Height question

[BFT3.2]

Ok corner balance experts, I have a odd question that I probably already know the answer to. My '88 has it's entire suspension rebuilt with 22/30 TB, revalved Bilsteins, Rebel bushings etc. etc. It's been lowered slightly below Euro height, aligned, corner balanced and corners like it's on rails, track and street. Has never showed the slightest over or under steer on the track since the rebuild. I know.. not driving fast enough.

I've recently had to make a temporary move until December and the roads here can be crap along with many steep driveways that Im constantly bottoming my front tow hooks on. Because I used the Rebel concentric washers on my front bolt of the A-arms the hooks sit much lower then my front spoiler. I know the permanent solutions but my question is if in equal turns of the front adjusters raise the front say a 1/2 to 3/4", how much could that theoreticaly effect handling on the street, if at all? If it did I'd imagine it would be pushing? Later or when tracking I would lower them back down the exact amount of turns.

Just came to me right now, would I lose my front alignment doing this?

Thanks and sorry for the long winded question.

[Discseven]

BF... I tried a few different front height settings just to experience difference in handling/cornering---a recommended experiment if you like that sort of infogathering. I did continuously adjust front toe as I recall. DIY with a "C" configured copper tube setup. Wheels have to be aligned to start with... equal turns on each side when adjusting. Flat, smooth pavement required. Measuring delta between forward and rear of rim to see toe. Obviously nothing to do with camber.

[Flieger]

The corner balance will stay the same if you raise both fronts exactly the same amount.

Alignment will change. Toe is about 0.375 degrees/inch and camber is about 1 degree/inch change when starting from stock ride height.

[stlrj]

Originally Posted by BFT3.2

It's been lowered slightly below Euro height, aligned, corner balanced and corners like it's on rails, track and street. Has never showed the slightest over or under steer on the track since the rebuild. I know.. not driving fast enough.

Could you post the resulting alignment printout in order to compare before and after?

[Trackrash]

I actually do this on my car. I marked my bolts after I adjusted my alignment and balance.

I adjust my bolts from this point about 1/2 a turn to raise the front for around town driving. I have not noticed any problems. However, I only put a few thousand miles a year on the car presently.

Probably up to one turn would be acceptable. You will notice that the front height will change some between a full and empty tank of gas, so some adjustments shouldn't make much difference.

[Jesse16]

Agree with Gordon. No height measurement or situation is ever completely static (car full or luggage and gas is much lower). You could adjust temporarily and likely never know the difference. Eventually tires might wear different and in a performance situation, it won't be as good.

[ClickClickBoom]

If your ride heights are the same, go out and brake to threshold, if neither front wheel is locking consistently, your balance is close. I have intercomp scales and have done 20 or 30 corner balances to date on 2 cars. I can corner balance the front with the braking method to about 30 lbs difference. Confirmed with the scales afterword. Mess with the rear and it's a different basket of ice cream.

[BFT3.2]

Thanks for all your input guys, really appreciate it.

My take away is that if I raise the fronts the exact amount of turns equaling about 1/2-3/4" rise, my toe will only change less then 0.375 degree. A amount I assume that would not have a drastic effect if I didn't re-align for it, as it's only for a couple months of occasional driving. Since Im raising, would that lead to a toe out? Im currently at zero toe.

@Stlrj, I won't be having it re-aligned so won't have a before/after.

@Trackrash -I'll crank them both 1 full turn and see how much of a raise I get. I've been driving around with no more then 5 gallons in the tank to keep the front up. Sick of going to the gas station. lol

@ClickClickBoom -I'll try some threshold braking before and after and see if anything changes.

[J-Mac]

Up = toe in..

[BFT3.2]

Originally Posted by J-Mac

Up = toe in..

ahh, thanks J

[ClickClickBoom]

Just did a corner balance, my threshold braking method was about 15lbs L-R front difference. I am back to about 6 lbs front difference. I adjust a couple of turns on the side of the road and re-check the braking. Bring it home and check the heights and adjust if necessary. It took more time to drag the scales out and jack the car than it took do recorner it. Bout 30 minutes from scales under the bench to back in storage. I bought them on eBay, was the only bidder, one of the best tool values yet! If you are changing less than an inch in ride height, don't worry about the toe, unless you are already at one extreme or another.
Think about the relationship between the steering rack and the tie rod angles, raising the rack causes the outside end of the tie rods to droop, and swing towards the center of the car, ding, more toe. If your rack is below the tie rods, raising the rack would cause less toe.

[Flieger]

corner balance scales will pay for themselves with all the flat spotted tires the other method will involve.

[ClickClickBoom]

Originally Posted by Flieger

corner balance scales will pay for themselves with all the flat spotted tires the other method will involve.

Vast difference, working up to heavy braking, if the tires are gone because of a few momentary lock ups, practice makes perfect. I can tell initial setup with a medium braking effort and adjust to less than 30 lbs, with maybe one 1/2 second lock up.
I agree on scales, I use both methods depending on what's happening. I imagine once my suspension set up is finally tuned, the scales wil go into dust collector mode, again!

[BFT3.2]

Originally Posted by ClickClickBoom

Think about the relationship between the steering rack and the tie rod angles, raising the rack causes the outside end of the tie rods to droop, and swing towards the center of the car, ding, more toe. If your rack is below the tie rods, raising the rack would cause less toe.

Makes total sense once you visualize it like that. Thanks

[ClickClickBoom]

Originally Posted by BFT3.2

Makes total sense once you visualize it like that. Thanks

Just finished my suspension upgrade, my poor floor jack is exhausted! Never thought I would be this deep into suspension design/modification. The PCar is wonderfully (mis)adjustable, but a little messing about, and it starts coming together. I stared at the Sander t-bars and other kit for more than 2 years, partly because other stuff was on deck, and partly from the unknown factor.
Cheers
Eric

[BFT3.2]

Originally Posted by Trackrash

I actually do this on my car. I marked my bolts after I adjusted my alignment and balance.

I adjust my bolts from this point about 1/2 a turn to raise the front for around town driving. I have not noticed any problems. However, I only put a few thousand miles a year on the car presently.

Probably up to one turn would be acceptable. You will notice that the front height will change some between a full and empty tank of gas, so some adjustments shouldn't make much difference.

Gordon, just a measurement fyi, I just raised both fronts two full turns and gained just over a quarter inch or about 9mm. I'll run it like this for a little and see if it's enough to minimize/eliminate my tow hooks occasionaly scraping. I took your advice and marked the bolts with a white paint pen.

*Update: After driving her about 30 miles, the 9mm rise has grown to about 18mm or 3/4". Didn't feel any adverse effect from the toe changing ever so slightly (under 0.375 degree). Works for now..