I have a 2003 ZO6 and I have lowered it (some of you have seen pictures of my updates). Removed BOLTS in the front and lowered in the rear on longer bolts.

I am seriously considering getting SWAY BARS. Curious what others here would recommend and/or have done.

Thanks in advance.

BTW, if any of you have the specifications on the sway bars and the comparisons to others on the market that would be great.

I posted this up in the ZO6 Discussion area, but figured I would get some good tips here also.

Micah

 

Here is a link to a chart that has the relative stiffness of the stock and some of the other sway bars that you could put on your car.

http://www.pfadtracing.com/photos/da...Comparison.jpg

Unfortunately adding stiffer sway bars to your car is basically worthless.

The reason for that is that if you have longer bolts in the rear with stock shocks the rear shocks are very close to bottoming if they aren't already. Since you are basically sitting on the bump stops there is little or no motion and the sway bars aren't going to make any difference. Also the jammed up rear suspension won't hold it's alignment. If you hit much of a bump the bottomed out shock will wedge the rear alignment excentrics out and you will be headed back to the alignment shop.

The maximum amount that you should lower a C5 is about 3/4 of an inch and you can do more than that with the stock bolts. More than that and the handling will suffer because the suspension geometry is also out of whack.

Sorry if it doesn't look a nasty, but before you can start to work with sway bars you need to get the car up to where the suspension will start to work again.

 

Thanks for the info. I am not going to do anything with my SWAY BARS, but I am going to look into COIL OVERS. If I could find a decent set for a decent price, I will do it.

Again thanks.

Micah

 

awesome post, helped me to as i also have my Z slammed on a Zip Kit.

 

You have to cut the bushings to get more than 3/4 right?

 

No, if you lower it all the way on stock bolts, without touching the bushings, you have gone too far. You can lower it in the front to within about one or two threads from bottoming out the stock bolts and still keep the geometry ok. In the back you will typically see about two threads on one side and about 4 to 5 threads on the other.

 

hmmm,

I followed the write ups in the DIY sticky Rear has 2 threads over the top of the nut, fronts were moved counter clockwise until it stopped and then back 1/4 turn like in this write up.
http://www.frankhunt.com/FRANK/hobbi...5_Lowering.htm

did I go to far?

 

No, you are probably ok if you have Z51 or Z07 springs. If you have base springs you are probably a bit lower than you should be.

I wish the idiot who did such a nice writeup would take it down. If you follow it you will indeed lower the car, but you will absolutely screw up the corner weights and balance of the car. These cars aren't level and if you turn the screws like they are describing you will end up with a mess. Also you should never measure from the fender lips. The fender lips are plastic that is just hung on the car and are all over the place. You should measure with the factory tools, or measure from just ahead and behind of the front and rear jacking points on a FLAT surface.

If your car is stock it was set properly from the factory and the height is right RELATIVE TO THE CHASSIS, which is the important part. If you lower the car from stock, turn the adjustment screws in equal increments from side to side. That is turn the front screws an equal amount from side to side. In the front it also helps to turn the screws in full turn increments. This keeps the orientation of the front pads the same and the car won't take as long to settle out. Turning them until they bottom and then back 1/4 of a turn assumes the car and the spring are level and is not the right way to do it. Same thing for the rear, turn them equal amounts from side to side, but you don't need to turn them in full turn increments. You will find that typically one screw is about 2 or three threads different from the other. THAT IS NORMAL. If you turn them to the same length you will screw up the balance of the car.

If you have already gone in and messed with the bolts you have lost the setup that the factory put into the car in the first place and to get it right you should have the car corner weighted. If you don't want to do that you can get close by finding a flat surface, (and no most garage floors aren't nearly flat enough) like an alignment rack, and measuring so that the front jacking point is between 4.25 and 4.5 inches from the ground and equal on each side, the rear is 1/2 an inch taller.

 

It is a z51, man I wish that there had been one post like yours within the hundreds saying that it was perfectly good to go to lower the car like that. Not one person said it was a bad idea until the day after I done it.
Great

 

99 vert- ZO6 springs and sway bars, 18" wheels all around.

I followed the various stickys and posts like this one

http://www.frankhunt.com/FRANK/hobbi...5_Lowering.htm

but I'm still having a problem: When lowering, after I unload the spring, I still have a great deal of resistance when turning the adjustment screw either way. It feels like I'm fighting the cushion. Is the cushion supposed to be loose when I unload the spring? Is the metal washer between the cushion and spring supposed to be loose or is it threaded or is it attached to the cushion?

Any comments appreciated.

 

With the suspension hanging did you make sure and put a jack just under the spring itself? Many of the threads here say that sometimes if it wont turn after jacking the spring it may need a shot of WD40 or PB blast

 

What do you mean setup the chassis from the factory? I'm sure they have a ride height setup, but that would be it. No corner balancing thats for sure. I would think that most guys that don't what or need corner balancing, should just find a ride height they like within the factory specs, then level left to right.

Steve A.

 

Meaning measure at the frame and not the fenders. You have to be sure you are on a totaly level surface, not your garage floor in most cases.

 

Yep - used a wood block to position the lift point as far outboard as possible on the spring in the A arm opening and used WD 40 several times above and below the spring.

Is this procedure in the Service Manual?

 

The factory has a set of tools and they quickly get the car set to the right ride height, and, while the car isn't corner weighted all that well it isn't too bad and it still drives fine. Most street drivers wouldn't feel the difference between a car that is corner weighted properly and one that isn't so if you aren't racing the car just setting it to a proper ride height at the jacking points is close enough. If you are really serious and/or are racing the car, getting it corner weighted is a good thing, since it's a lot nicer to have the car turn the same in both directions.

I've been an instructor at a lot of drivers schools and got to drive some cars that were lowered by somebody who didn't know what they were doing, and really had the corner weights screwed up. It was amazing how much the car would push turning one direction and how loose it was going the other way, or if the car was lowered too much how it was LOOSE EVERYWHERE, and the owner couldn't understand why he was getting waxed by cars that were way up in the air compared to his...

I have a friend who I set up his car by phone from 2,000 miles away. Gave him all the setup specs and he went out and hammered his autocross competitions, who were, incidentally, driving a car that had been one of the top running cars in the country when driven by an autocross master. He comes back and says "I'm beating these guys, but my car is a lot higher than theirs, shouldn't I lower it more and then I'd be faster???" My answer was.. "NO LEAVE IT ALONE, the reason you're faster is that they are too low!!!" He kept calling me every couple of weeks with the same question, but he's managed to leave it alone and continues to regularly beat the guys with the lower car.

We've always been told that lower cars handle better, and in theory that's true, but when you take into consideration things like camber curves and real world suspension, often, lowering reaches a point where it just doesn't pay off any more.

 

thanks "Solofast" for the post. By the way I measured my car and the front is 4 3/8" The rear is 4 1/4" Not sure if I want to raise the back. This is for autocross only.

Steve A.

 

I've found that with the rear ride height that low that the car wouldn't put down power very well coming off of corners. This was with custom Koni's that are shorter than the stock shocks so bottoming wasn't an issue. We did this on a test day and jacked it back up and the bite came back. Easy enough to try on back to back runs. You can change the rear ride height a couple of turns between runs if you had to. Test days are your friend....

 

Actually before I had these coilovers, I did some testing on my old suspension. What you described is exactly what happened to me. I went real low and the back was all over the place. I almost couldn't drive it. I think I'm going to raise the car to 4 7/16" all the way around. That should get me in the ball park.

thanks,

 

Where are you measuring the 4 7/16"?

 

I'm pretty sure it's right in front of where the rear jacking puck goes..on the frame.