According to my 1970 Buick catalog, the Wildcat came standard with H78-15 tires, however according to another source, since my car has the optional rally wheels, my particular car would have come with L78-15 tires. According to tirerack.com, the modern replacement for these would be 225-75/R15 or 235-75/R15, respectively. I am not liking the options I have for 75 series tires, so I was thinking about moving to a 70 series tire on the same rims. I know this will reduce the height of my sidewall a bit and there would be an issue with the speedometer/odometer if either of these two instruments were working properly (they are way down on the list.....) but I was wondering what other issues may I encounter? Do I have to make any modifications to the suspension to maintain ride height? I'm hoping to have the 'Cat back on the road by this upcoming weekend, I'm just waiting on the shop to install the new headers, and new tires are next on the hit parade. Would appreciate any insight. JM
No need to worry at all about the suspension and ride height. You can always get the speedometer issues under control with a gear change once you know what tires you will use. An H78-15 was 28.36" tall with an 8.55" section width A P235/75R-15 is 28.29" tall A P235/75R-15 is 28.88" tall An L78-15 is 29.30" tall with an 8.85" section width How about a P255/70R-15 tire at 29.05" tall http://www.tirerack.com/tires/tires...88969&ef_id=V23tfQAAABx49xnp:20160626170134:s Honestly, you could go with any of those tires.
I wanted 70 series tires for my '68 Wildcat and the best fit I found is 235/70/15. They look and fit great.
