Hello everyone,

I have a 94 with the stock 9.5 sawblades on the rear and 8.5 on the front.

Is there any potential problems with putting 9.5 wheels on the front as well? Are there enough handling benefits to make it worth doing this?

Thanks

 

I think the ability to rotate tires makes it worth it. Face it, vette tires aint cheap. Wider fronts will reduce understeer and it'll tend to follow road ruts more, but keep it properly aligned and it'll be no problem.

 

I almost went to 9.5's all around also but ended up keeping the 8.5's up front. The shop that I go to says that the 275/40's up front really make the car push through tight turns and is harder for daily driving like u-turns and such. I even dropped from a 255/45 to a 245/45 up front and really feel some good grip around the normal 90 degree turns I take everyday. The wider tires up front will only help you through very high speed turns. I'm glad I didn't go with the wider tires up front...

 

I do not know your answer, I have a 95 with the same 8.5/9.5 with base suspension. The 94 ZO7 has 9.5s all around but with 40/75 tires front and rear I did not check the other changes, I would think to further improve you would need the rest of the package, which I would like to do myself, but its way down on the list.

N7

 

Go ahead - the only thing you may notice is a little more wandering or pull in some of the road ruts.

The 91-92's had 9.5's on all 4 corners.

 

My 94 Z07 has them on all four corners, it's no problem what-so-ever. It's NO harder to drive in regular situations than any thing else I have driven, and the benefits of being able to rotate your tires is worth something. I say go for it.

 

Keep in mind that in 94 the 9.5" wheels on all 4 corners only came with the Z07 suspension which also had stiffer springs and bigger sway bars. Think of all this working together as a system.

I have a 93 coupe with the FE1 suspension and run 9.5" wheels on all 4 corners when I autocross. It does help the car turn in better but I found that the back gets a little loose on me. I drive to the events on the 9.5" wheels and street tires and have not found it to be as bad as I had anticipated but am mindful of the setup and am typically not too aggressive with it.

My recommendation would be that if you do it be very mindful of how the car handles until you've driven it enough to get a good feel for it.

 

And when astock says driven it a little bit, he doesn't mean 1000 miles of going to the grocery store. He probably means driving it a little harder in turns, curves, etc., still in a safe manner so that anything that happens, you can catch it or correct for it.

If you think about it, even with the base FE1 suspension vs. the Z07 or whatever else came with 9.5" wheels up front, by going to a larger wheel and possibly a larger tire up front, you are potentially increasing front end traction. Not always, but much of the time that is what will occur.

Therefore, the resultant "feel", and fact may be that you decrease rear traction. Maybe not, but it might feel that way with a newfound, higher cornering ability of the front end. Playing with suspension and traction is a very tricky business and usually best left to racers. So much depends on a whole bunch of factors that computers now help make the decisions.

That said, however, there's probably no downside to your going to 9.5" wheels up front, slightly wider tires up front, possibly even matching the size you have in the rear, and doing the rotation suggested, if that's even possible. With many wider tires, the only "rotation" possible is front to back and that does very little to even out wear or prolong tire life. It is only when you can do the modified X that you gain increased tire life through rotation.

Good luck and don't be worried about going to larger front wheels and larger front tires.

 

Yup, that's what I meant ... thanks.

That's a great summary of everything I've read about C4 setup and why I advise a bit of caution. When I go to the track (instead of autocross) I make sure to use the stock 8.5" wheels up front so I don't get caught. Tail happy is bad when there's concrete around.

A good alingment will go a long way as well.

You can also buy a symmetric tread directional tire so you can swap them on the wheels after about half their life.

 

I'll have to politely disagree because I wear out rears twice as fast as fronts. I'm pretty mild on the throttle too. If I could swap front to rear, the fronts could take half that wear, which would increase tire life alot.

 

I see the terms "understeer" and "C4" used together occaisonally and am confused.

I have the stock 255/45 front tires sizes on my C4 and have never, repeat never, experienced understeer.
I have autocrossed the car, and not infrequently drive very spiritedly on the local mountain roads in the company of other Corvette Forum members.
I deal with oversteer often , but not one time has the front end pushed.
Under what conditions do you guys who have experienced this phenomena get understeer??

So as not to jack the thread; 9.5's will work fine on the front.

Larry
code5coupe

 

I on the other hand will off you one caution, depending on where you drive.

My 95A4 came stock with 9.5" on all 4 corners because it has the Z07 & FX3.

On my daily drive I travel hiways that have experienced a lot of very heavy truck traffic and as a result there are rutts in all of the lanes. You don't normally notice these ruts in regular cars and in fact you can hardly see them BUT with those wide tires in the front 275-40-17 the front end of the car "yanks" in and out of the ruts. To someone driving behind me it looks like I am weaving from one side of the lane to the other & back again.

I'm used to it now and it doesn't bother me too much but it did take a while to get used to.

 

I'm with Mr. Peabody. My 90 has the same sizes as his and really no problem.The rut thing is really weird when you first run into it but it has only happpened to me on long trips. Local roads do better for me.

 

I rarely notice it on the street or the track where the turn radii are bigger and more "sweeping".

I first noticed the car's "push pig" tendency when I started autocrossing. Of course I was bone stock on street tires with a factory spec alignment. Tire width up front is only one of the things that goes into understeer. Others are suspension setup, stiffness (camber brace, x-brace etc) and alignment. My understeer has improved as I improved each of those other things.

Autocross course setup goes into it as well. On a longer course with more sweepers I don't notice as much as on shorter tighter courses.

 

I also used to experience it during tight autox going into a corner hot. Now it's more of an even drift....or it actually turns in now. Of course, there are methods to counter the understeer, but it's much easier now.

 

Put one of your rears(9.5) on the front to check if the offset is right before you buy any.
I was also thinking about doing this.