Can someone tell me what the differences are between the suspension of both cars. I’m new to C4’s and in the process of buying a Z07 from a board member. Is the track width between the two different?
Thanks.

 

Track width is not meaningfully different. Any difference would be as a result of the GS's wider rear tires...which should have the centerline of the rear tire in the same place, but may not due to fitment.

 

So you’re saying their track width is about the same? I’ve heard pros and cons on the Z07 suspension, how does the GS compare?

 

One way to look at it is this:
Grand Sport (RPO Z16) was basically an appearance package except for 1 important feature. Grand Sports were all 6-speed manuals and thus came with the more powerful LT4 engine and slightly wider rear tires.Otherwise it's special paint, stripes and different style wheels.

Z07 is basically a handling and suspension package.... well actually there was no Z07 option for 96 instead they reverted back to calling it Z51. The Z51 package consisted of special shocks, front and rear springs and different bushings.

One could order a 96 Grand Sport and also order the Z51 suspension option.

Note that an easy way to see all of these different options by individual year is to invest $20.00 and buy yourself a copy of Mike Antonick's "Corvette Black Book"

 

It would help considerably if you posted a snapshot of the SPID label of the car you're considering. Without knowing that it's silly/foolish to attempt any comparisons of anything to a '96 GS The purchase of the 'Black Book' other than some interesting information you might use the $20 for some fuel.

 

Here’s a pic. It’s a ‘94

 

As Mr. Peabody said it is all about the handling.

Front sway bar is 30mm solid steel instead of the 24mm tubular or the 26mm tubular on ZR1 cars. BIG difference in handling.

Springs are 46% stiffer than even on the ZR1.

Steering ratio is quicker than standard.

Wishbones are slightly different, again to stiffen up the handling.

The ZO7 car was designed for the track or aggressive handling as GM stated. Many people did not like the additional stiffness of the ride even in the lowest setting of FX3 shock setting due to the items mentioned above. I never could push myself to find out exactly what the extreme limits of the handling package could do. But it will out handle the GS in stock trim but is not as fast or as good an investment as the GS. But it is amazing to feel how flat the ZO7 will corner at speed and I do miss that after selling my 92.

 

The regular 17x9.5 wheels have an offset of 56mm, whereas the Grand Sport 17x11s have 50mm offset. So the centerline of the GS wheels should be 6mm further out on each side, and the rear track would be 12mm different, I would think.

 

I’m going to be putting C6 Grand Sport wheels on it. I believe they will fit without any issues.

 

Ummm, you didn't tell us you were asking about a C6 Grand Sport! And no, they will not fit without issues. I'm guessing the car you're buying is newer than 1987 if it has the Z07 package? If so, it came with 17x9.5 et56 rear wheels. Depending on the year, it will have the same size up front or 17x8.5 et56. The C6 Grand Sport came with 18x9.5 et40 wheels up front. I believe they will fit with 275/35/18 tires, but with 16mm less offset they will sit that much further outboard than stock 17x9.5 et56 wheels or 29mm further outboard than 17x8.5 et56 fronts.

The rear C6 GS wheels are 19x12 et59. First things first: they have 8.82" backspacing, and that's about 0.82" too much. You will be hitting things on the inside. You'll need 7/8" or 21mm spacers/adapters to push the wheels out far enough to fit on the inside edge. But if you do that, they are going to poke outside the fender edges by about 1" on the outside edges. The only way to accommodate these would be by cutting the fender arches a lot bigger and then fitting real flares (not the stick-on 96 GS silliness), or to adapt a ZR1 rear body (if that's even possible). Aside from all that, the smallest tire that is approved for 19x12 wheels is a 325/30/19, but at 26.7" in diameter it's really too tall. A tire that tall might fit without rubbing if it were a lot narrower, but in this case it's going to be sticking out of the fender arches and will tear it up any time you go over a bump. You could stretch a 305/30/19 onto that wheel, but it's not the approved fitment still doesn't really solve the poke. The bottom line is that 12" wheels really don't fit on a stock C4 unless it's a ZR1, and especially not if they are 19s.