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Discussion Starter #1
I dont know if anybody can give me guidance here, but ive got a '74 Alfa GTV with Alfaholics fast road C package. At VIR yesterday I had the car weighed to see how she sits. The numbers are, with me in the drivers seat...2413lbs total, Left Front 747lbs, Right Front 614lbs, Left Rear 529 and Right Rear 523lbs. SO by my reading the front left is pushing down too hard, so I should remove some of the washers ive got between the lower control arm and spring pan on the left side so as to compress that spring more. Does that sound right? I think ive got about 1/4 inch stack of washers in there, so I could reduce that and that would help balance the front end, right?
 

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Rockie, unfortunately, there isn't any good way to move weight from the left front on a street car. It is always going to be the heavy corner with you in the driver's seat. If you haven't already, you can definitely improve things by moving the battery to the right rear of the car.

As for corner-weighting the car with your current set up, here is how to think about it. Any time you "jack up" a corner, you transfer weight to that corner AND the opposite corner. So if you remove a washer from the right front, you will add weight to the right front and the left rear. Ideally, you would like to have the sum of the RF and LR weights to equal the sum of the LF and RR. You currently have 47.4% of the weight on the RF and LR, so you could benefit from moving a little bit of weight.

Keep in mind that in the effort to get your corner weights right, you can easily mess up your ride height. Remove too many washers from the RF and the car will be visibly lower on the LF. I typically try to get the front ride height equal on each side, and then move the corner weights around by adjusting the rear springs. But that is a lot harder to do on a street car.

Finally, don't forget that to do the corner weights right, you need to first disconnect the front and rear sway bars. Then, after everything is set, reattach the bars, adjusting them so that there is no preload with you in the car. That is, if you have adjustable sway bar links.

I usually try to get the race car to within about 1/2 of a percent on the cross-weights. But some of my buddies make fun of me while reminding that no race track is perfectly flat!
 

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Discussion Starter #3 (Edited)
[QUOTE=
As for corner-weighting the car with your current set up, here is how to think about it. Any time you "jack up" a corner, you transfer weight to that corner AND the opposite corner. So if you remove a washer from the right front, you will add weight to the right front and the left rear.

Genericwood-

Im not sure I follow exactly....ive got 133lbs more weight on the Left Front, so youre saying jack up the right front to compensate. I suppose lowering the left front would do the same? it seems counterintuitive, since I read to think of it like a chair with one chair leg is too long. If ive got too much weight on the frontleft, then jacking the front left spring tighter would make it sit more level. The car sits about 1/2 inch lower on the left front, so removing washers from the LF springpan would raise that corner and keep this corner from pushing into the ground so much...

If I follow your directions...I guess I can acomplish removing weight from the left front by adding washers to the leftfront springpan, thereby lowering that corner?
 

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Rocky, your chair analogy is a good way to visualize it. But you are thinking about it backwards. When you remove washers from a spring pan, you are raising the spring perch and that corner of the car. This causes that corner of the car to take on more of the total weight of the car, along with it's opposite corner. If you had a race car with springs on threaded coil-over shocks, it would be really easy. To increase a corner weight, you would just thread the spring perch higher on the shock. To reduce it, you would thread the perch down.

The fact that the left front is already noticeably lower suggests to me that you should do any balancing at the rear of the car. Putting a spacer under the left rear spring would shift weight to the LR and RF, getting you closer to balanced cross weights.

My '66 GTV race car is under weight, so I have to run a LOT of ballast. Corner weighting is made much easier when you have 150 pounds of lead to put wherever you want it! It is especially helpful because I weight 240 pounds.
 

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Discussion Starter #5
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Forgive my Dislexia...I added about 1/8 inch of washers lowering the LF springpan yesterday, and how the FL sits lower than the right by almost 5/8 to 3/4 inch. Maybe I would be better as you say to put the LF as it was, and add a shim to the left rear, but I was pretty closed to balanced accross the rear before I started. How thick of a shim on the LR would you guess as a starting point? I cant remeasure corner weights until I go to the track again anyway.
 

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Maybe I would be better as you say to put the LF as it was, and add a shim to the left rear, but I was pretty closed to balanced accross the rear before I started.
Just remember that you can't really change the overall left to right balance by shimming springs. You started with 52.8% on the left side, and that is pretty close to what you will end up with, unless you start moving components. So either the front, the rear or both are going to be imbalanced from left to right. That is absolutely normal on an unballasted car with the driver sitting to one side.

With the LF quite a bit heavier than the RF (unavoidable!), the LR has to be heavier than the RR to get the cross weights correct. So don't worry about the LR and RR being balanced. Your LR/RF are 127 pounds lighter than the RR/LF. So to balance perfectly, you need to move 63.5 pounds from the RR/LF to the LR/RF. And the LR shim would help you do that. A wild guess would say maybe an 1/8" spacer would do it? On the other hand, you may want to level up the front end and then figure out what is required at the rear.
 
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