[ZeeOhSix]

Can the Z06 be lowered from the stock ride heigth an inch front and rear without getting a 4-wheel alignment??

I'm assuming it can be put to the lowest position the adjuster bolts will allow it without realignment (gives you less than an inch I think).

What's the concensis on how much lowering is allowed before realignment of the wheels is required?

 

[N4C5S]

It's split 50/50. Half say they realigned and it was off. Half say they have thousands of miles with no alignment and no wear.

But, for the price of an alignment, can ya argue? /phpBB/images/smiles/icon_smile.gif If you do have it done, make sure they have the *Z06* specs.

JC

 

[JimGreen]

I have alignment tools, so when I lowered my Z06, I checked before and after each step. On my car, the rear could be lowered 1" and it stayed within specs, although with slightly more negative camber. Lowering the front 1" adds about 0.7 to 0.8 degree of negative camber, which was too much. In fact, it started off uneven left to right (but still within spec). I had to remove the upper control arm from the frame to be able to get out the adjusting bolt, so I added appropriate sized washers between the frame and A-arm until the camber came back to about 0.6 ro 0.7 degree negative both sides. When you take out negative camber at the top, the toe-in becomes much higher, so I then had to adjust that too.

When you adjust camber by adding shims at the top or adjusting the eccentrics at the bottom, be sure you change the front and rear ends of the A-arm the *same* amount, or you will change the caster.

The bottom line is that you will need to have the alignment adjusted, no way to avoid it. This is also a good time to tidy up a sloppy factory alignment. I would not drive the car long without doing this, because the tires are very expensive, and bad alignment causes greatly increased tire ware.

 

[JBsC5]

Go with the 15 mm maximum drop on bolts that GM recommends on ZO6 as per members of this site that answered that question for me and you should be in spec for high performance alignment maximum..

Of course its always smart to do alignment after a short period of time..but as many report not necessary..

Id suggest following the gm performance guideline on lowering amount...

Not because I know better..but because I don't..BTW..Im very pleased with the 14mm drop and its subtle effect on looks and improved cornering..

Much nicer all around..took the highboy look away..and flatter through the S's..

no problem with ride what so ever..smooth as silk..No shock absorber or bushing issues either.

This is not a flame to others who went lower..I'm sure they know more than me..

All I am saying is that I am glad I did the 14mm's for my personal application..(Instead of 4 fingers between tires and wheelwells..its 3..)

I would do it again in a heartbeat and would recommend it to anyone who is looking for something but doesn't want a drastic change..

I would consider it a nice balance for the street..

(PS..Some might say its not enough..but this is just my personal choice)

Good luck..there is no wrong decision just different expectations.

 

[hcvone]

I have seen some cars that were lowered that were still in spec, but then others that were way off.

 

[c4c5specialist]

Hi there,
Any time there is any movement in any suspension component, or any part is undone, and then retorqued, an alignment is done.
There is no question, as even when I install an exhaust, and the rear lower pinch bolts are removed to aid in the removal of the rear sway bar, some settings change.
There is NO reason to take chances, as when you change ride height, you change your settings. Its that simple.
Best to all, c4c5

 

[ZeeOhSix]

Thanks for some great inputs guys. I've noticed the rear seems to sit alittle higher than the front anyway, so I'll probably just lowrer the rear to match the front, or take the suggestion to just go the 15mm lowering max with the bolts. I just want the air gap between the tires and fender lips to be matched, and follow the tire's circumference evenly. Sounds like the 15mm drop will do that /phpBB/images/smiles/icon_biggrin.gif.

From what JimGreen said, it sounds like just lowering the rear alittle would not effect the rear wheel alignmenet very much, and it would probably still remain within the alignment range. /phpBB/images/smiles/icon_cool.gif

 

[DJWorm]

Three pearls to remember:

1. Whenever you make any suspension change, adjustment and/or component change ALWAYS....ALWAYS check the alignment specs.

2. Always align the vehicle with a half tank of gas.

3. Always align the vehicle with the driver in the drivers seat.

 

[JBsC5]

This is just my opinion..I would maintain the front rear height ratio..of course take measurements on all four sides before you start so you have a baseline..

So if you change the front 15mms..do the same amount in the back..

Could I be wrong..you bet...but I would imagine it would be a safe bet...

Suspension geometry and vehicle dynamics in various situations is way beyond my understanding so I just try to tweak what GM gave us..

Lets face it..the zo6 right off the showroom flow is truly one of the finest handling machines ever built..as reported by experts and owners alike..I'd just tweak it..

Only because..I'm not really sure of all the variables that can exist..

BTW..I hired International Motor Performance shop to lower my car..they only charged about an hour or so labor..which was certainly worth it..they accidently turned the front bolt the wrong way...it was not too big a deal..a pia for me as I had to drive back....but not too bad as they just threw it back on the lift when I went back to correct the error..also..it takes about a day or so for the front to finally complete its lowering process..

Good luck and I can assure you that if you stay within GM's performance street guidelines..you'll be satisfied when your finished.


After driving around for a few weeks but before you get an alignment if you decide to do that as suggested by c4c5specialist....you can always change the suspension settings further if you so desire.

Good luck with whatever you decide.

You have a great car!!!!!

Enjoy.

 

[ZeeOhSix]

On 2001-08-12 22:44, JBsC5 spewed forth this drivel:

Good luck and I can assure you that if you stay within GM's performance street guidelines..you'll be satisfied when your finished.

Where are the GM performance street specs listed .... in the owner's manual?

 

[JBsC5]

I got the information from a ZO6vette.com member on a lowering thread..I don't remember which thread but I believe it to be on zo6vette.com.



I would assume it was in video or owners manual. Thats what the gentlemen who posted said.

If you decide to go more drastic..I would imagine it would be fine..


I wanted to to do this in a mild approach because of the area I travel. I am pleased with the results as I am sure the guys who slammed their cars..

Different strokes for different folks.

 

[JBsC5]

I brought up the thread on GM's recommendation for lowering..

I hope this helps. Check it out.

Good luck.

 

[JimGreen]

The GM specs for alignment are in the GM (Helm, Inc.) service manuals. There is also a good set of "performance" alignment specs on the Mallett web site under instructions for installing their lowering kit.

Adjusting alignment is no big deal. All you need is a flat and level garage floor, a camber gauge, and an optical toe gauge. (The measure-the-difference toe gagues work, but a Corvette is too low to use this type -- works great on pickups.) If you don't have alignment tools, borrow a set from a racer friend.

Having said that, you can measure all the alignment settings before you start, and see how well GM did at the factory. Then lower the car to your tastes and see what changes. Very educational.

If you don't understand what alignment is and what to change, there are many good race-car books that explain all the theory and practice. It's not rocket science. With alignment tools, if you make a mistake it will be immediately evident, and you can go back and correct your mistake.

P.S. I have a Dunlop optical toe gauge and a knock-off of a Dunlop camber gauge made by Performance Marketing of California. (The camber gauge also measures caster.) I have had these for 25 years since my racing days. They were a little pricy, but have come in handy again and again, and can be paid for with 5-6 alignments at current prices.