What’s the best size tire to run on a 86 gt I was thinking a 215 up front and a 235 in The rear. Here is a picture of the rims

Rims will get cleaned up and resurfaced before going on the car but want to do everything all in one shot

I run 215/45s and 235/45s on my 88s.
Are all four wheels the same size? If that's the case, and you want to be able to rotate them, you can also run 225/45s on all four.
If you are going for maximum performance, staggered will be better.

In order to not upset the speedometer or FDR accuracy; I used 17" tires that had nearly identical outer diameters. I used 225 x 45-17 rear and 205 x 45-17 front. The wheels are 7.5" wide/35mm offset and are lighter than stock The car handles great but it does ride rougher than it did on the OEM 15" tires. To soften the ride on my next restoration I may go with 16" tires that have a taller side wall

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quote Originally posted by Dennis LaGrua: In order to not upset the speedometer or FDR accuracy; I used 17" tires that had nearly identical outer diameters. I used 225 x 45-17 rear and 205 x 45-17 front. The wheels are 7.5" wide/35mm offset and are lighter than stock The car handles great but it does ride rougher than it did on the OEM 15" tires. To soften the ride on my next restoration I may go with 16" tires that have a taller side wall

to address the ride, go with 245x54-17 on rear and 215x45-17 on front. works well with the 17 by 7.5 by 35mm ofset. its the most you can go on stock rear springs and front wheel well space.