NoOne

Figures...I get the brakes pretty much straightened out. The Wildwood H's were mostly upto the task for the day. The new alignment worked out well and I had an instructor in the car with me for our 3rd session.

At Grattan driving hard 1/2 the track and not quite as hard the other 1/2 to listen to the instructor I turned 1:36 compared to Z06's with slicks around the 1:31 mark.

I was going to go for another hot lap but decided to pull in.

I get out of the car and see the passenger rear is sitting really low. The drivers side is ok but the tire is up in the wheel well on the passenger side.

We jack up the car and find the leaf spring about 3" from the passenger side bracket is splitered and broken.

Anyone seen this before?

I dont' know when it broke but the guy with me said he thought something was wrong with my diff because the car seemed to oversteer an aweful lot.

Its a Z06 bar...so now I need another but I'm more concerned about why it broke. Alignment was as suggested here, 0 toe and -.75 camber.

I was really happy with the car and thought after practice I could shave a second or two off of the that 1:36.

I'll have more detailed photo's tommorow, have to run back upto the track with a trailer to get the car.

At least its a simple fix but would like to know some idea's on its cause.

Thanks,

Z11409

Plastic springs delaminate once and a while--order a custom spring from Vette Products

Bill Dearborn

Especially if something damaged them first.

Bill

John Shiels

I heard chemicals may affect them also.

NoOne

I called Vette Products...still deciding what I might do.

Is there any way shape or form an alignment can effect this?

I just had it done a few days before hand.

About a week ago we were driving to work during some 'spirited' driving when on decel from a speed involving 3 digital and no decimals I'd hear a clunk from the rear, a HARD clunk. Did this 3 times and never again.

I thought maybe one of my cutouts was hanging off and banging the floor pan.

Put it up on a hoist, inspected everything, no problems. Drove it over 700 miles and never heard it again but maybe that was the start of this.

I inspected the rear suspension last night while bleeding the brakes and all that, no obvious problems.

I wish I knew when on the track it happened, but just saw it after the session.

One more question though...basically the car is sitting on the jounce bumpers in the shock. How can I prop it up?

I am going to trailer it but even on the trailer there is going to be suspesnion motion and over Michigan roads on a 140 mile trip I don't want to beat the hell out of the shocks and upper shock mounts since they will now take all of the load.

Not to mention with my tire size if there is even a .5 inch of movement I'm going to start banging the wheel well and possibly doing body damage.

We were thinking of cutting some blocks of wood to prop up the rear suspension a bit. I'd rather put some distance between the body and the tires.

Any idea's?

Good thing is, the brakes held and after a few laps with the instructor there was a huge improvement and I was much more confident with the car.

UstaB-GS549

I can't imagine an aligment breaking a spring. I think the composite springs are sensitive to chemicals and scratching or notching.

Sorry about your predicament. Something relatively soft to block up frame at rear by tie down slots?

stairman

you said something about your cutouts, do you mean exhaust cutouts, if so and you are dumping your exhaust before the rear spring, you melted the spring, I have seen it several times.

jra140

There's no way the alignment caused the spring to break. There are plenty of people running way more camber (myself included) that haven't had any issues. I'd say it just delaminated on its own, or had an impact in that spot that weakened it.

On another note, I see you're running Wilwood H's. How many Grattan days do you get out of the pads/rotors? Just curious.

Don't worry about towing the car home on the jouce bumper. When Corvettes (and every other car produced) are on car haulers or railcars getting shipped from the manufacturing plant to the dealer, they tie them down on the jounce bumpers all the time. Yes, it's a lot of load, but it won't hurt anything.

NoOne

I didn't want to imply the alignment did it, was just wondering if it could have helped it...

My exhaust cutouts are quite a bit ahead of the spring but it is in the 'path' of the exhaust gas so its a more likely possability.

The H pads worked well for the short time I was actually on the track. Alot of that had to do with the instructor though, I was braking far far less than before and not pulling off as much speed to make corners on the wrong line.

They did what I wanted them to do which is drag me down from 135mph on the straight to a reasonable speed for the turn and they did it everytime without tapering...so far...

Here is one more question...how tough is this spring change?

I have two ideas...one bring it home and fix it which involves alot of jockeying to get it on the trailer, get the trailer, 4 hour round trip, more like 5 towing or getting a new spring and fixing it at the track.

If I were to jack up the car, unload the spring, it just 'slides' out correct, slide the new one in, mark the bolts ahead of time and set the height somewhat close, drive it home and then set it up right?



Thanks

John Shiels

my bet also I had a muffler come loose and it melted the rear fascia of the car bad.

DALE C

The cutouts did it the only springs I have ever seen break have been from exhaust heat

99BlackZ51

A T1 Z06 at the June Sprints last weekend had the exhaust break loose in front of the rear spring and then the spring broke half way through the race.