Topic: Wheel Size
in Forum: C3 Engines, Driveline and Handling
Already a Member?
Click Here to Login
Not yet a Member?
Click Here to Register for Free!
SPONSOR AD:: (Our Sponsors help support C3VR)
First off...Welcome to the C3VR Forum! This is a great place to learn and help each other!
I'm not a 100% sure on an answer for your question, but I believe the biggest tire size that came from the factory on stock 8 x 15 inch rims for your '77 was a GR70-15. I don't know what the metric equivalent would be for that. The tires you are running now is a pretty wide "sneaker." I guess if the tires aren't rubbing or showing abnormal tire wear, then I don't see a major problem. My '81 came through the factory with P255/60R15, which isn't all that much smaller. The standard tire was a P225/70R15. So it's not like it's causing a lot of stress on the suspension. But if your suspension is old or original and loose, I would highly recommend that you go through the entire front and rear suspension. Balljoints, springs, A-arm bushings, etc., "the whole 9 yards."
Sarge
I'm not a 100% sure on an answer for your question, but I believe the biggest tire size that came from the factory on stock 8 x 15 inch rims for your '77 was a GR70-15. I don't know what the metric equivalent would be for that. The tires you are running now is a pretty wide "sneaker." I guess if the tires aren't rubbing or showing abnormal tire wear, then I don't see a major problem. My '81 came through the factory with P255/60R15, which isn't all that much smaller. The standard tire was a P225/70R15. So it's not like it's causing a lot of stress on the suspension. But if your suspension is old or original and loose, I would highly recommend that you go through the entire front and rear suspension. Balljoints, springs, A-arm bushings, etc., "the whole 9 yards."


Grand Blanc, MI - USA
Joined: 8/7/2002
Posts: 544
Vette(s): 1979, 350sb, as my kids affectionately call it "shit brown" Corvette purchased in 1996. 84,000+ miles. Not a show car, but I love her just the same.
Everytime I see a post from Pozz33 all that shows in the post are X's, and an update line. What's the deal?


Fabulous site, I'm thrilled that I found it. Sarge, I have a stock 80 L82 and want to put new tires on it. I see your's had 225/60's on it. I am looking for performance and width. Is this size my best bet? I have 225/70's now. Anyone? Thanks!
Andrew
Andrew

Former Member
Send PM
BRADENTON, FL - USA
Joined: 8/4/2002
Posts: 669
Vette(s): 1972 convertible 350 auto trans, delux int, air, ps, pb, t/t wheel, pw, 79,000 org miles Rare one year only color
here's a link for tire size conversions. remember changing the height will change your speedometer readings.
http://www.miata.net/garage/tirecalc.html new link fixed
|UPDATED|2/4/2003 7:24:37 PM|/UPDATED|
http://www.miata.net/garage/tirecalc.html new link fixed
|UPDATED|2/4/2003 7:24:37 PM|/UPDATED|
|IMG|http://www.c3vr.com/member_uploads/1301_1400/1333/br80.jpg |/IMG|
Former Member
Send PM
Castle Rock, CO - USA
Joined: 4/21/2002
Posts: 179
Vette(s): 1973 T-Top
1993 Coupe
Hi All,
On all of my vettes I have put 255/60-15 tires. This was the largest tire available on vettes from the factory in 1981 and 82. (Earlier maybe) On cars earlier than this, you will experience slight tire rub in a hard right turn (steering wheel locked to the right). The rub occurs on the frame, not bodywork but the tire comes very close to the body and I don't think a larger tire would clear the fender in all conditions.
Alex
On all of my vettes I have put 255/60-15 tires. This was the largest tire available on vettes from the factory in 1981 and 82. (Earlier maybe) On cars earlier than this, you will experience slight tire rub in a hard right turn (steering wheel locked to the right). The rub occurs on the frame, not bodywork but the tire comes very close to the body and I don't think a larger tire would clear the fender in all conditions.
Alex

Alex,
I think I'm sold on the 255/60's for my 80 L82. Now, I'm also going to order a new speedometer. I don't like the stock one that only goes to 80 mph. Is there something that needs to be done to the new one before it's installed so that it reads accurately with the new tires? Sorry from all the dumb questions. I really think this place is a temendous asset to a new "old" Vette owner! Andrew
I think I'm sold on the 255/60's for my 80 L82. Now, I'm also going to order a new speedometer. I don't like the stock one that only goes to 80 mph. Is there something that needs to be done to the new one before it's installed so that it reads accurately with the new tires? Sorry from all the dumb questions. I really think this place is a temendous asset to a new "old" Vette owner! Andrew

Former Member
Send PM
BRADENTON, FL - USA
Joined: 8/4/2002
Posts: 669
Vette(s): 1972 convertible 350 auto trans, delux int, air, ps, pb, t/t wheel, pw, 79,000 org miles Rare one year only color
try this link http://www.s-series.org/htm/calc/calcs.htm seems the one i posted above is now dead. you figure the tire diameters of your stock tires and your new ones. going from 225/70-15 to 255/60-15 will result in a 4 tenth of an inch smaller diameter and will only change your speedometer 1 mph slower that actual speed at 60 mph. not worth changing the speedometer gear in my opinion.
PS i have removed whitewalls in this photo and have replaced them with 255-60-15 BF Goodrich RWL new updated photos to follow
|UPDATED|12/8/2002 10:46:24 AM|/UPDATED|
PS i have removed whitewalls in this photo and have replaced them with 255-60-15 BF Goodrich RWL new updated photos to follow
|UPDATED|12/8/2002 10:46:24 AM|/UPDATED|
|IMG|http://www.c3vr.com/member_uploads/1301_1400/1333/br80.jpg |/IMG|
in Forum: C3 Engines, Driveline and Handling
SPONSOR AD: (Our Sponsors help support C3VR)