Some one please Help. I ordered new Wheels and tires for my 95 Z28.
C6 rims 18x9.5 w/285/40/18 in back 18x8.5 in front w/ 255/45/18

Now my problem is: Anytime I have a hard weight transfer whether shifting lanes real fast or flooring the car from a stop my tires scrape right on top of the middle of the tire. Now if I drive the car nice or crank the wheel all the way I have no clearence issues or tires rubbing. The only thing I can think might be the problem is when I bought the car the previous owner had new Monroe sensitrack (Sp?) shocks put in. I've read that the dual valving technology is horrible for sports cars. Would new springs help or new shocks? I know motors well but not suspension. I see a lot of people with bigger wheels than I have and they don't seem to have problems. Any advice would be greatly appreciated

NOTE FROM MODERATOR - This is going to be a confusing thread, because it was posted in three separate threads on two different forums. I've "merged" all three threads, so that everyone who reads the question can see all the answers and info that was given in all the threads.

 

Those are some pretty big rears... I've run 285-35's with only a bit of edge scraping on hard corning... I've currently got 295 30's and they have not scraped at all yet.

 

Your problem is not "big wheels"..... its "big tires". You bought the wrong sizes. A 285/40-18 and a 255/45-18 are both 27" tires.... almost 1.5" larger than your stock tires. A better choice would have been 245/40-18 in the front and 285/35-18 in the back. The 27" tires will slow your car down, like installing lower numerical rear gears. It will also throw your speedo/odo off by more than 5% if your car left the factory with the 245/50-16 tires.

Your second issue may be the offset of the wheels. What is the offset of the front and rear wheels? If the offset isn't correct, the tire may not be sitting in the center of the wheel well.

 

Well I'm stuck w/ the wheel /tire size I have. I would think there still is a way I could set up my suspension to handle the 1.4 inch increase in size for my car. In theory wouldn't lowering the car by 1.5 inches be the same as increasing the wheel /tire size by 1.5 inches ? Plenty people do that w/out problems.

 

Well I'm stuck w/ the wheel /tire size I have.( 27.0 inches) I would think there still is a way I could set up my suspension to handle the 1.4 inch increase in tire size for my car. In theory wouldn't lowering the car by 1.5 inches be the same as increasing the wheel /tire size by 1.5 inches ? Plenty people do that w/out problems. If I added Bilstein Shocks and springs would that do the stop the tires from hitting the wheel well? I would hope that would help fix the problem and make the car ride better than compared to the Moroe Sensitracks shocks and 70,000 mile springs that did most of their time in storage.


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Opinions And Sugeest Help Please !

 

Some one please Help. I ordered new Wheels and tires for my 95 Z28.
C6 rims 18x9.5 w/285/40/18 in back 18x8.5 in front w/ 255/45/18

Now my problem is: Anytime I have a hard weight transfer whether shifting lanes real fast or flooring the car from a stop my tires scrape right on top of the middle of the tire. Now if I drive the car nice or crank the wheel all the way I have no clearence issues or tires rubbing. The only thing I can think might be the problem is when I bought the car the previous owner had new Monroe sensitrack (Sp?) shocks put in. I've read that the dual valving technology is horrible for sports cars. Would new springs help or new shocks? I know motors well but not suspension. I see a lot of people with bigger wheels than I have and they don't seem to have problems. Any advice would be greatly appreciated

 

Some one please Help. I ordered new Wheels and tires for my 95 Z28.
C6 rims 18x9.5 w/285/40/18 in back 18x8.5 in front w/ 255/45/18

Now my problem is: Anytime I have a hard weight transfer whether shifting lanes real fast or flooring the car from a stop my tires scrape right on top of the middle of the tire. Now if I drive the car nice or crank the wheel all the way I have no clearence issues or tires rubbing. The only thing I can think might be the problem is when I bought the car the previous owner had new Monroe sensitrack (Sp?) shocks put in. I've read that the dual valving technology is horrible for sports cars. Would new springs help or new shocks? I know motors well but not suspension. I see a lot of people with bigger wheels than I have and they don't seem to have problems. Any advice would be greatly appreciated

 

There is no simple solution... other than selling those tires on ebay and getting smaller diameter ones.

You could increase the height of your bounce stop... but that's dangerous... don't do it.

You could get coilovers with a high rate spring... then you could set the ride height to stock but the higher spring rate would limit travel, that would be reasonable but expensive.

You could take a hammer to the wheelwell and open it up some... but you probably won't get enough additional clearance to fix the problem.

I suggest you sell the tires and get one's that will fit.

 

Gonna move this one to general tech since your problem is tough to categorize easily. You might get better help there, too. Good luck!

 

what he said

the bigger tires do effectively raise the ride height of your vehicle and getting lowering springs would counteract that,

but it makes your poroblem worse, because the top of the tire gets closer to the inner fender it will scrape even more

you may be able to find tires with a smaller aspect ratio to effectively reduce the overall size of the wheel

you are probably better off getting a new setup

 

 

You've got three different threads going on the same topic.... this is not a good way to get answers. I'm going to merge all three in "General......"

I also resonded to your problem on another forum, telling you the tires were too big, and asking you for the "OFFSET" of the wheels. If I knew the offset of the wheels, I might be able to see if there is a solution, or whether the problem can not be solved.

But you ignored my request for the offset info, and came over here and started posting the porblems all over again.

If you want people to help you, you have to work with them by providing the info they request. Otherwise, you make the solution almost impossible. I'll back off from intruding in this one, because its not possible to help without the requested info.

Merging to "General.... " thread.

 

Jason....

He's already got three threads on the same subject. I moved an earlier one to "Suspension......" so he just reposted here.

I'm going to "merge" all three threads here on "General......"

 

I have 10 x 15 inch rims with 6 1/2 inch offset for the rears. On them I have 28 x 12 1/2 x 15 inch tires. I raised the height of the rear slightly with drag springs and had the rear fenders rolled. If I drive on the street they will still rub however they are fine at the track.

The fronts are also 28" tall and the tires definitely rub if I try and corner hard so I don't corner hard.

The real solution for you, because you care about street driving, is to install the appropriate size tires.