How to: Lower the C7
 

One of the vendors already did it. They say its similar to the c6. I am not familiar with either. I plan on doing it this weekend, I could do a write up, but I need the info / how to myself first, then I can document as I go and post up. Someone can link me to the thread or pm me that would be great.

Our kit will be out in a couple of days.
Justin

What is a kit needed for? Just wanted to drop with the stock bolts. Think I found it.

:lol:

That is a pretty inappropriate thread title for this thread. I was expecting instructions and pictures.

So what do folks do when they lower the car??? Guess what I am asking I get my ratchet on the bolts and count the number of turns I make to make sure each side of the axle is changed around the same amount?

Or do people just slam it down as far as they can? I mean do I just adjust the bolts as far as they will allow?

Or with all the variables in a suspension any I being too precise?

If you have one of the C7's that seems to sit high, you can lower it a bit to make it look better. You can count the turns, or measure and repeat. It takes a bit of driving for the suspension to settle after you do it.

You can use a floor jack and one jack stand. Jack up the car with the puck on the corner you want to adjust. Then put a rubber cushion on the leaf and a jackstand under it. Lower the car down so the jackstand pushes up on the leaf spring. The lowering bolt can be turned with a 10 mm wrench. Most cars only need 1/2" or 3/4" to look much better. Once you get some miles on the car you could have the alignment checked, it's not a bad idea anyway since the tires are expensive and factory alignments are not always perfect. Many have said that droping the car a bit on stock bolts does not affect the alignment much, if any.

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It appears some C7'ss must have been set @ the lower setting.

all the ones i've seen come through work (4 Z51s) look like 4x4s IMO. i'd like to see them lowered

I just finished lowering my Z51. I guess the results vary. I dropped mine as far as it would go. After a short drive, the measured results were 5/8" lower in front and 1-1/8" in the rear.

I'm pretty slow, and it took me about 2-1/2 hours to do it. The rear was the bitch, as I could only get about 1/8 turn with each try of the box end 10mm wrench. A ratcheting one is the ticket.

The front went easier with the tires removed as I could get about 1/2 turn. Remember to get the spring jacked up or the bolt won't turn at all. Look under the spring opposite the bolt head and you can tell when the spring is wound all the way. Mine stopped about 1/16" from full bottom.

Jacking up the spring will test your ingenuity if you don't have a bottle jack. I made some 2 x 4 chunks of wood that worked ok and used jackstands and a floor jack. Remember to jack the spring as far out to the outside as possible for maximum flex. Other than that things were pretty easy. Looks so much better. The body of the car at the front a-pillar now measures 5-1/4". From the factory, it was 6". That's the main part of the body, not counting the bolts and nuts that hang down below that.

When jacking the spring, the car came off the jack stand fairly high before it started to move, so I guess that's normal, either that or put 8 adults in the car for ballast.

Front fender lip at the wheel center, highest point, was 27-1/2" to the ground and after was 26-7/8"; rear measured 29-1/2" and after was 28-3/8. These numbers should help a baseline person maybe.

The spring pre-load adjustments can be used to corner-weight the car and that by using a weight scale under each tire.

More likely, just measure before beginning and then after lowering keep the front and rear heights in proportion and level the car side-to-side.

Now suppose the car is lowered the maximum but the right rear is lower than the left rear. And so the right rear needs increased spring pre-load to level side-to-side. Increased spring preload on the right rear raises the right rear but also pushes down on the left front and so there's the puzzle
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Does lowering the car change the ride of the car? Mark is stiffer or rougher? Picking my new C7 up this Friday an want to maybe lower it a little. thanks

Good information. Saved it for future reference. :thumbs:

this is a good thread that has pictures to help walk you through the steps along with some other good info that should answer most of your questions.
https://www.corvetteforum.com/c7-gen...nd-photos.html

Changes in spring pre-load don't physically change the spring and therefor the spring rate doesn't change. But the force range of the spring that is being used does change. And so less spring pre-load is a softer suspension while more spring pre-load is a stiffer suspension.

Here's a chart showing some stock spring with no pre-load:

http://www.sportrider.com/tech/146_9.../photo_01.html

Here's a chart showing showing a higher rate spring as compared to the first chart:

http://www.sportrider.com/tech/146_9.../photo_02.html

And here's a chart showing the stock spring with pre-load as compared to the first chart:

http://www.sportrider.com/tech/146_9.../photo_03.html


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Having lowered several C6's and now my C7, no difference in ride at all. You are not changing springs, spring rates or spring/suspension travel, just the relationship of the car body to the spring. If you don't greatly change just one corner, I believe you would be hard pressed to notice any handling change.

this is same as c5s and c6s