tire question
Thread Starter
Burning Brakes
Joined: Jan 2006
Posts: 1,019
Likes: 18
From: St. Louis MO
tire question
I have a 1980 vette. It has old Goodyear GT tires that are a 60 series. It tends to get pulled by road lines in the pavement. I need to replace these old Goodyear's due to age and I was looking at 70 series tires. Would that make a lot of difference in my ride?
Race Director
Joined: May 2006
Posts: 18,729
Likes: 2,579
70 series has a higher sidewall so the ride would be softer but the outside diameter has to be the same otherwise your speedometer will be off. If the 60 series tires are more than 10 years old just replacing them with new 60 series will soften the ride.
Advanced
Joined: Oct 2014
Posts: 55
Likes: 1
From: Woodland Park CO
Because the OD is the same, sidewall height will be the same. 60's are wider with more air volume so the ride will be somewhat smoother and increased footprint should improve handling slightly. Regardless, new tires are needed. Use the recommended air pressure on the door not the tire maximum. You can go +- 10% air pressure, lower for smoother, increase for mileage/handing if you want. Play with it some to your liking. Keep the same pressure fronts / different for rears and you can dial in some oversteer and understeer. Doing this may help groove wander.
I'm going from 70's to 60's on my 78.
I'm going from 70's to 60's on my 78.
