That's the exact set up I was thinking of - now it's a definite!!
Lowering and Bigger Wheels = ?
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From: Southwestern Ontario Canada
Lowering and Bigger Wheels = ? I am going to lower my vert with Eibach Pro-Kit springs (listed as 1.5" front and 1.3" rear drop). At the same time I am looking at Z06 wheels 18x9.5 up front and 18x10.5 out back.
Am I going to have any issues with this set up?
Anyone got pics of this set up?
Am I going to have any issues with this set up?
Anyone got pics of this set up?
No issues really. I have been runing 275/40/18 for a long time with Michelin Pilot Sport. The rim width I have on the wheels is at 9.5 front and rear. The WS6 has the jounce bumber spacers in the rear to keep the rear wheels from hitting inside the wheel well. My 18's have never hit.
The front tires did touch a very little the front of the wheel well when turning the wheels all the way in (or out). That went away after about 5,000 miles when the tire wore down a bit.
Side view and underside of WS6/18" wheels
Here the rear jounce bumper spacer. It bolts above that rubber piece (triangle shaped) that is on the chasis right above the rear axle outside the springs. WS6 jounce bumpers at SLP
The front tires did touch a very little the front of the wheel well when turning the wheels all the way in (or out). That went away after about 5,000 miles when the tire wore down a bit.
Side view and underside of WS6/18" wheels
Here the rear jounce bumper spacer. It bolts above that rubber piece (triangle shaped) that is on the chasis right above the rear axle outside the springs. WS6 jounce bumpers at SLP
The prokit for the ls1 drop it to low for the back of the verts, IMO. I just installed the front springs and cut about 3/4 turn out of my org. back springs and looks much better. I will have to get some pics for you..and oh yea..big tires do fit..I'm now running 305 on the back without any problem, although I did cut out my bump stops.
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Verdad Gallardo What I meant before is no issues with 18" wheels. This car has 18" front and rear - 285/40/18 Michelin Pilot Sport. You're gonn be bummed when you install what you think lowers these cars 1.3" or so. It will be much lower and ride like a brick. The WS6 verts are heavier then a coupe, the car everyone tested spring height on. I know, I have been through 3 sets now and have wasted lots of $.
The best setup with 18" wheels is to keep the stock front springs and get Koni struts. Koni's have a upper and lower spring perch. By using the lower spring perch you actually lower the front about 3/4". That with the fact you get another 1/2" from a bigger wheel fills up the wheel opening, maintains ground clearance, and lowers the car.
On the rear of these cars springs from the factory are a variable rate of 130-180 lbs. The WS6 has a jounce spacer that keeps the axle from going up into the wheel well. It is there to stop the OEM 17" wheel from hitting up into the wheel well. You can see this part by looking through the top of your rear wheel. It's an aluminum spacer between the chasis and the rubber bumper that hits the axle. POINT HERE IS: The vert is heavier in the *** and these springs and can't go down enough (cus of the spacer) to get into the 180lbs part of the OEM spring. We bottom out more. Use the BMR rear coil springs. They lower the rear 1" and are rated at 145-170 lbs. This way you will bottom out less with a starting point of 145lbs. and lower the rear 1".
This is just some of the reason they are so much heavier. The frame sections outlined in blue are ONLY on a convertible. Basically they create a full frame under the car. There is also more metal inside the car under, behind, and to the sides of the rear seats.
Vert .vs Coupe chassis difference (pics)
The best setup with 18" wheels is to keep the stock front springs and get Koni struts. Koni's have a upper and lower spring perch. By using the lower spring perch you actually lower the front about 3/4". That with the fact you get another 1/2" from a bigger wheel fills up the wheel opening, maintains ground clearance, and lowers the car.
On the rear of these cars springs from the factory are a variable rate of 130-180 lbs. The WS6 has a jounce spacer that keeps the axle from going up into the wheel well. It is there to stop the OEM 17" wheel from hitting up into the wheel well. You can see this part by looking through the top of your rear wheel. It's an aluminum spacer between the chasis and the rubber bumper that hits the axle. POINT HERE IS: The vert is heavier in the *** and these springs and can't go down enough (cus of the spacer) to get into the 180lbs part of the OEM spring. We bottom out more. Use the BMR rear coil springs. They lower the rear 1" and are rated at 145-170 lbs. This way you will bottom out less with a starting point of 145lbs. and lower the rear 1".
This is just some of the reason they are so much heavier. The frame sections outlined in blue are ONLY on a convertible. Basically they create a full frame under the car. There is also more metal inside the car under, behind, and to the sides of the rear seats.
Vert .vs Coupe chassis difference (pics)
Originally Posted by UK-WS6
Hi there, I got a 2002 WS6 T/A 'vert
Standard 9.5 x 17 WS6 wheels
I was looking at the Eibach Sportline Springs - Pontiac Firebird V8 Convertible
Pontiac Firebird V8 Convertible
front/rear
1.8/1.8 $244.30
Will 1.8 front and rear be too low.
I don't have any plans for a wheel change
Graham
Standard 9.5 x 17 WS6 wheels
I was looking at the Eibach Sportline Springs - Pontiac Firebird V8 Convertible
Pontiac Firebird V8 Convertible
front/rear
1.8/1.8 $244.30
Will 1.8 front and rear be too low.
I don't have any plans for a wheel change
Graham
I've been down this road. My car, dropped that much, had basically no front susupension left. Not only was it not enjoyable to drive, no one really liked riding in it and all thought something was wrong with the car.
Here is a pic of my car lowered using Hyperco springs with a claimed drop of "1.25" that ended up being around 2". I talked to the President of Hyperco (best produced spring on the planet) and like many others he said they have never tested springs on verts. Notice how little suspension travel is left (the shaft of the shock not the coils).
Also notice that this does not have the OEM shock boot on (which has a bump stop built into it). That is the plastic tube looking thing that slips over the shock shaft to keep debris off of it (bleow pic). Inside that tube and at the top is a giant rubber washer about 1" thick.
THUMB IS ON SHOCK BOOT
This is an integral part of the front suspension. Many do not put this back on the car during a spring change because they are using cheap spring compressors that clamp on the outside of the spring, with prongs that go inside the coils. The shock boot hits the clamps so they just leave it off, or for other reasons I have no idea why.
UK WS6,
If I were you I would look on my front and rear coil springs. There will be a tag with the GM part # on it. You can use that to determine what spring rate is on your car now. Once you know that then go to this chart to see who makes the amount you might want to lower your car.
http://www.angelfire.com/my/fastcar/suspension.html
Remember that what you read on how much will drop a car, on a vert it will be more.
If I were you I would look on my front and rear coil springs. There will be a tag with the GM part # on it. You can use that to determine what spring rate is on your car now. Once you know that then go to this chart to see who makes the amount you might want to lower your car.
http://www.angelfire.com/my/fastcar/suspension.html
Remember that what you read on how much will drop a car, on a vert it will be more.
No one makes springs specific for a convertible, they just exclude it. No one has tested on verts.
Here is what Eibach does (Excludes vert) on their site.
That should tell you something right there.
Don't even think about buying a spring that says it will lower
a car 1.6 or 1.4"s if you own a vert.
Here is what Eibach does (Excludes vert) on their site.
That should tell you something right there.
Don't even think about buying a spring that says it will lower
a car 1.6 or 1.4"s if you own a vert.
PHP Code:
1998-2002 (Incl. Trans AM & Convertible)
Product Front Rear Comments Part Number
ANTI-ROLL-KIT 35mm 25mm 3831.320
PRO-KIT 1.2 in 1.2 in 3870.140
SPORTLINE KIT 1.6 in 1.4 in Excluding convertible 4.7038
Originally Posted by MiaSSmaro98
well u can slove the problem by buying coilovers w/ ur personal spring rate.and thst wat i think im goona do.any opions?
I'm also not interested in the way you have to modify the rear end or do welding for coil overs and using the shock mounting location for the new spring perch.
With the Global West weight jacks & shorter springs in the rear you just don't know what the real spring rate will end up being. Possibly could go through several sets of springs to find the right set up and keep from bottoming out. Verts have a heavy *** and they do not provide any data on what you're really getting.
Thread Starter
TECH Regular
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From: Southwestern Ontario Canada
So I'm keeping my stock 17" wheels but I want to lower my vert.
What is the best spring to use?
Who has pics? Who has comments on the ride/handling?
What is the best spring to use?
Who has pics? Who has comments on the ride/handling?
