Rear Tyre Clearance

[richardz]

I have recently put on wider wheels/tyres (17x11 with 315 Goodyears) on my 95 convertible with soft FE1 suspension. The tyres hit the outer rear guard lip on corners and road dips. There is just under 3 inch vertical clearance with no one in the car. Do I 1) adjust the spring end bolt length for more vertical clearance 2) change to different shocks 3) change the rear spring 4) play with spring spacers or 5) some or all of the above. The service manual indicates 2 different springs (yellow/green code) is this right and if so which one is stiffer? It would make my dentist happier if this was fixed as I would not have to grit my teeth whenever I see a road dip coming - and there are plenty down here.

 

[c4cruiser]

Which 11" wheels did you get for the rear?? There are 2 different 17x11 wheels, each having a different offset. The wheel used on the rear of the ZR-1 has a 56mm offset and the 11" wheel used on the rear of the Grand Sport had a 50mm offset.

If your rear tires stick out about 1" from the edge of the wheelwell, that would indicate the ZR-1 offset. If it's more like a 1/4" , that would be the GS offset.

These wheels are pretty pricey to replace so I would recommend a stiffer shock to help control the body. The FE1 springs are pretty soft so going to the Z07 springs may help some, but that could cost as much as replacing the rear wheels. Although the stiffer springs and shocks may work, you will most likely become your dentists best friend and he could even finally be able to buy that new Mercedes he's always wanted

I would not really consider raising the ride height as that may very well change the handling characteristics in a negative way. If you decide on springs, the front and rears should be matched as a set. Don't mix a HD rear spring with a soft front one.

 

[VeTTeKraZy]

If your car isn't lowered, and your shocks are original (8 years old), it's likely your shocks are toast.

I had to replace the shocks on my 96, everytime I hit a "small" bump in the road the car would react violently and practically pull the steering wheel out of my hands! Horrible!

 

[Tuna]

I tend to agree with VeTTeKraZy on this one - shocks.

I have the ZR1 offset wheels on my 92 and the tires stick out. It is an FX3/FE1 car and the tires do not rub the fenders. It is at the delivered ride height.

 

[Hotred94]

I also have 315s on my 94, and they will hit the fenders. The danger is not that you will mess up a tire when this happens, it is that you will split your rear body panel with a bad jolt. Here is what I recommend. 1. Put on new shocks (I use KYB gas). 2. Make sure all the rear end spring spacers are on the top of the spring. 3. Adjust your tire bumpers down a whole bunch (you'll need to experment with your setup but I put in 4 fat washers). 4. Avoid potholes; that's why they made vettes handle.

Good luck!

 

[richardz]

Thanks all,

The offset for the wheels are correct (I got them from CWS) and the ride height is standard. I like the solution with 1) shocks 2) re-arranged spring spacers 3) suspension bumper adjustment. The car has done 36K miles so I will do all of the above. It takes a week or so to get stuff so I will let you know how it went.