tire specs
Thread Starter
Heel & Toe
Joined: Jul 2005
Posts: 19
Likes: 0
tire specs
I have a 1992 coupe, the book says the original tire was a 275/40zr/17. it had when I bought it P245/45Z/17 89Y. Does this sound good or bad. advantage or disadvantage. I do not race ect. normal road driving. On it now are Goodyear Eagle F1.
Team Owner
Joined: Aug 2005
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From: Riverside County Southern California
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92 came from factory with 275/40ZR17 all around (GY GSC tires). You may install 285/40ZR17 all around. Maybe the previous owner was weak or a lady and he/she could not steer the tires. 
Burning Brakes
Joined: Oct 2004
Posts: 920
Likes: 1
From: Shelby Township Michigan
Some have put the smaller width tires on their cars due to the road surfaces they are driving on. Helps reduce the "slalom" affect from the road ruts.
I prefer the original set up using the 275/40 series tires. The overall diameter difference is only .2" and the overall circumference is only .6" difference.
Good luck,
Dino
I prefer the original set up using the 275/40 series tires. The overall diameter difference is only .2" and the overall circumference is only .6" difference.
Good luck,
Dino
Melting Slicks
Joined: May 2004
Posts: 2,286
Likes: 2
From: Stamping Ground KY
you best check to make sure the wheel widths are correct, you should have 17x9.5 all around. It's possible, but unlikely, that the previous owner downgraded the wheels for some reason.
I don't think the smaller tires would affect regular driving performance any. I agree with dino about the ruts.
The small difference in circumference means that you're speedometer isn't off by much.
I don't think the smaller tires would affect regular driving performance any. I agree with dino about the ruts.
The small difference in circumference means that you're speedometer isn't off by much.
Burning Brakes
Joined: Oct 2004
Posts: 920
Likes: 1
From: Shelby Township Michigan
Most OEM wheels have the sizes stamped or etched on the back side. If not, you can try to measure thru a wheel opening. A 9.5" wheel will measure over 10" from flange to flange.
Good luck,
Dino
Good luck,
Dino
Advanced
Joined: Aug 2003
Posts: 90
Likes: 1
From: Davidsonville MD
Also important is to make sure that the front and rear tires are the same diameter. The 255/285 OEM combo have the same diameter front and rear. The 275/275 OEM combo of course do, but they are slightly smaller in diameter than the 255/285 combo. The 275/315 combo have the same diameter front and rear.
So why is this important? Because the ABS works best if all the tires on the vehicle are the same diameter. That way the tone rings on each hub that send pulses to the ABS are sending approximately the same signal, and the ABS likes that. If you have different diameter tires, the ABS works harder and cannot work as well, because it is designed to try to make all the tires operate at the same speed. The same goes for the ASR; it doesn't work as well when the front and rear tires are different diameters.
So why is this important? Because the ABS works best if all the tires on the vehicle are the same diameter. That way the tone rings on each hub that send pulses to the ABS are sending approximately the same signal, and the ABS likes that. If you have different diameter tires, the ABS works harder and cannot work as well, because it is designed to try to make all the tires operate at the same speed. The same goes for the ASR; it doesn't work as well when the front and rear tires are different diameters.
