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For those of you who own a C5. I bought a set of Michelin Pilot sport tires on sunday I have larger wheels in the rear on my 99 so I thought why not get larger tires??? Heck the car doesent hookup anyways so what would it hurt.

So I bought 295/30ZR/18 and had then installed. Well when I left the tire store my car's computer went nuts..... The traction control was turning on every 8-10 seconds and I could not drive over 45mph. Turns out the side walls were just a hair shorter compared to the 275/40ZR/18 I was replacing, there for the rear axle was turning faster due to the smaller diameter tire.
As a result the rear axle sensor and trans sensor were not reading the same road speed and when that happens the traction control turns on.

I was lucky Big O tires took them back and in return sold me a complete set of Continental Contri Sport2's for $900.00 out the door mounted and balanced.
 

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The the first time I have ever heard of that, pretty interesting. Plus, it's cool the tire shop took care of you. :thumbsup:
 

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JWOLIN said:
For those of you who own a C5. I bought a set of Michelin Pilot sport tires on sunday I have larger wheels in the rear on my 99 so I thought why not get larger tires??? Heck the car doesent hookup anyways so what would it hurt.

So I bought 295/30ZR/18 and had then installed. Well when I left the tire store my car's computer went nuts..... The traction control was turning on every 8-10 seconds and I could not drive over 45mph. Turns out the side walls were just a hair shorter compared to the 275/40ZR/18 I was replacing, there for the rear axle was turning faster due to the smaller diameter tire.
As a result the rear axle sensor and trans sensor were not reading the same road speed and when that happens the traction control turns on.

I was lucky Big O tires took them back and in return sold me a complete set of Continental Contri Sport2's for $900.00 out the door mounted and balanced.


I forget the exact percentage but I believe that any variation in wheelspeed greater than 10% (after compensation for the built in front to back variation) will set off codes.
 

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ALWAYS try to make sure the overall diameter is the same. There are several online calculators, and Tire Rack should be able to help you out too.
 

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I have run a number of different size, and the TC alway learns the new sizes. But then I have had other friends that went through what you did. MY 2k C-5 had a hard time even with stock sizes now that I think of it.
 

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actually it is a very common problem when the rear tire diameter does not retain the smae diamter variance when compared to the front .....


the rear tire diameter is apporox. 1" taller than the front. This is done to maintain proper sidewall deflection rates front to rear since the front wheel is 1" shorter than the rear
 

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Humans and Computers

"Logical is a very natural state to be in if you're a computer. Computers communicate with their programs and with other computers logically and they are perfectly happy with this arrangement. Computer users are not very logical. In fact they are anti-logical, and sometimes do things that the computer simply doesn't understand. Because humans are so unbelievably illogical, computers refuse to except that humans are their creators."

From: The Life of a Computer Arbitrator
by Doug Chick


Traction Control Computers--->:nuts: <---Owner's Freedon of Choice in Tires

:partyon:
 

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DC Crew
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Re: Humans and Computers

SilverBear said:
"Logical is a very natural state to be in if you're a computer. Computers communicate with their programs and with other computers logically and they are perfectly happy with this arrangement. Computer users are not very logical. In fact they are anti-logical, and sometimes do things that the computer simply doesn't understand. Because humans are so unbelievably illogical, computers refuse to except that humans are their creators."

From: The Life of a Computer Arbitrator
by Doug Chick


Traction Control Computers--->:nuts: <---Owner's Freedon of Choice in Tires

:partyon:
Yea.... how can you run 205-15" tires on gold wire wheels if you are going to piss off the TC?
 

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Tire Size changes and Active Handling SYS

Patrick said:
I have not heard of that before. Very interesting.
Well IF you read the informative (but long) posts... you'd know:

Bosch 5.3 301 Revisited:

"Something to keep in mind concerning the Corvette active handling system is that changing the tire/wheel size can upset the operation of the Bosch 5.3 system. If someone has installed a different size tire or wheel, the wheel/tire combo may not work well with the stock calibration of the active handling system."

http://www.digitalcorvettes.com/forums/showthread.php?s=&threadid=14738

C'ya again I'm sure... :bang :bang :bang
D
 

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Active Handling

Is there a way to reset the Active Handling calibration? I had to have an OEM tire repaired (big-ass screw). Now I'm alerted to Active Handling being activated at speeds above 70mph. I need to replace the run flats, too. Very little tread. Could that set off my AH?
 

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I agree with Luke,the front and rear tires have to have the 1" diference in height,the computer compairs front to rear revolutions,i put the same size tires as you,but i changed the front also.Kept the 1" difference and all is well.(it has a slight give or take to include tire wear).
You can even run 19s on all four corners,but you would have to use a 30 series profile in the front and a 35 in the rear.From the same tire manufacturer.
Or 35 series 19 inch front...40 series rear same manufacturer.Make sense.
I'm suprised that such a small change set it of though,could be a coincidance,try to pull the codes,some codes are for active handling,and some codes are for the VSS -Vehicle speed sensor.

Just for compairision reasons.I went from
Front- 245/45/17s ...to 265/40/17..
rear -275/40/18s.....to 295/35/18s...not a problem for me.
 

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I always thought that is why Predetor has that
program built into their unit. So you can change
tire size and not go through all that BS.
 

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So when I replace the tires on my Z to 305/35 ZR18 nitto 555r will I have any problems?
 

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Re: Active Handling

Vettemeister said:
Is there a way to reset the Active Handling calibration? I had to have an OEM tire repaired (big-ass screw). Now I'm alerted to Active Handling being activated at speeds above 70mph. I need to replace the run flats, too. Very little tread. Could that set off my AH?
C5Doug said:
I always thought that is why Predetor has that
program built into their unit. So you can change
tire size and not go through all that BS.
The computer can be re-calibrated:

Predator

C'ya
D
 

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what do u recomend on a 91 vert

unclephilly said:
Thank gawd you didn't get Firestone. I had a pair and let me tell you THEY SUCKED!
:huh:
 
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