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Discussion Starter #1 (Edited)
First off, I want to apologize off the bat if any of the answers to my questions are available in searchable threads. I'm barley learning my way around a car and sometimes get confused "decoding" directions because I'm not fully literate in tire sizes, rim sizes and car's in general just yet.

With that out of the way, I was hoping you guys could provide me with a few answers to questions I have. I want to lower my 1996 Caprice but also would like to increase the rim sizes to a 20-22". My questions are:

- How would I go about doing this? I have the stock Impala wheels on currently. If I lowered my vehicle with the stock rims on, then purchased new rims would I have to "re-adjust" anything? What would I have to re-adjust?

- Where would I take my car to get professionally lowered?

- Would the lowering or rim size increase put unnecessary stress on anything else in my car? Is there a "right way" to avoid this?

- Would staggering my rims put unnecessary stress on anything else in my car?

Thank you in advance.


- Mark
 

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If I lowered my vehicle with the stock rims on, then purchased new rims would I have to "re-adjust" anything? What would I have to re-adjust?

If you lower your car (or raise it with big rims) you will have to re-align the front end to keep the camber correct. You will also have to loosen and re-torque all the control arm bushings since they are now twisted out of proper position. You will also have to deal with the messed-up geometry of the driveshaft, since the universal joints at the transmission and differential are now unnaturally angled and will be more likely to wear out/break.

- Would the lowering or rim size increase put unnecessary stress on anything else in my car?

Yes. The balljoints will be at abnormal angles and more likely to wear out or break. The car's suspension will not be in the range it was designed for and will be more likely to bottom out on bumps. You will have to re-calibrate the speedometer for new tire diameter. With big rims, they will be more likely to get damaged when you hit bumps or potholes, gas mileage will be worse because of the increased weight of the rims, the car will be slower and will take more distance to stop.

If you're relatively new to owning your car, I think you'd be better off spending the time and money to make sure the basics are okay--things like cooling system, suspension and steering, tune-up parts, brakes--stuff like that.
 

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If I lowered my vehicle with the stock rims on, then purchased new rims would I have to "re-adjust" anything? What would I have to re-adjust?

If you lower your car (or raise it with big rims) you will have to re-align the front end to keep the camber correct. You will also have to loosen and re-torque all the control arm bushings since they are now twisted out of proper position. You will also have to deal with the messed-up geometry of the driveshaft, since the universal joints at the transmission and differential are now unnaturally angled and will be more likely to wear out/break.

- Would the lowering or rim size increase put unnecessary stress on anything else in my car?

Yes. The balljoints will be at abnormal angles and more likely to wear out or break. The car's suspension will not be in the range it was designed for and will be more likely to bottom out on bumps. You will have to re-calibrate the speedometer for new tire diameter. With big rims, they will be more likely to get damaged when you hit bumps or potholes, gas mileage will be worse because of the increased weight of the rims, the car will be slower and will take more distance to stop.

If you're relatively new to owning your car, I think you'd be better off spending the time and money to make sure the basics are okay--things like cooling system, suspension and steering, tune-up parts, brakes--stuff like that.


WOW. While some of the above is true---just barely but true, just do it and have fun with your car
 

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I have lowered my car, and there are a few things you have to consider. If you are going to just put lowering springs on the car, it is relatively easy. The only major issues will be tire clearance, camber on the front, and springs falling out at the rear. If you are going to use drop spindles in the front, you should have the front end aligned, but you will not have to make the camber adjustment for the spring lowering. You will have to check for tire clearance because the drop spindles move your wheel out about 1/3 to 1/2 inch.

Front tire clearance is only a problem if you get wide tires. A 27 inch 255 tire (same as a stock Imp tire) will not give you any problems until you get really low (2 1/2-3 inch from stock Caprice height). Rears are a little more forgiving in width up to 275. You can stagger the rims and it will not hurt anything as long as the rims have the original offset. I believe it is -6mm. The distance from the outside of the backside of the rim to the contact surface should be about 1/2 inch more than 1/2 of the width of the rim. For example a 9 inch wide rim would have an offset of 5 inches (9" divided by 2 +1/2") from the back of the rim

You will have negative camber in the front when you lower it with springs. Measure the front axle center line (take the dust cap off) to the bottom of the fender vertically before you do anything, and write it down. Once you have lowered it with springs, measure it again to find the drop (you have the drop without tire variables). You have to remove 0.030 in shim thickness from all alignment stacks for each 1/2 inch of drop to correct for the negative camber. If you do not, it will wear the insides of your tires excessively, and quickly. For example, if you drop it 2 inches that will require the removal of 0.120 of shim thickness.

The rear springs from most manufacturers are shorter than the OEM springs. If you do not put a drop shock (short) on the rear, when you jack the car to change tires, the springs will fall out, because they do not touch the top spring perch when the suspensions drops. You can use your original shocks if you have a 3-4 inch piece of exhaust pipe welded to the center of the top perch. It keeps the spring aligned so that it lands on the spring perch when you lower the car again. You should also consider using a tiewrap to hold the spring on the axle perch to keep it from slipping off when the car is jacked.

Mechanically you will not hurt the car by dropping it. Depending on who many miles are on the front components, and while you have it apart, you might consider new bushings and ball joints just to replace any unknown worn out parts, and give it a fresh feeling suspension. You can buy complete new arms with BJs and bushings from Rock Auto for less than having yours rebuilt, unless you are using upgraded aftermarket wear parts. Always tighten the bushing bolts when the car has full weight on the suspension to avoid stress on them which would shorten their life substantially. Because of the limited access to the underside after lowering, you may have to have it on a rack to tighten them. While I had my car on jackstands with the wheels off, I jacked up the respective arm until the frame lifted off of a jackstand then tightened the bolts. The rear is similar to the front for the bushings, but you do not have completely separate action for each side. I would also update wear parts for the drop spindles as well.
 
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