Pete68
05-02-2023, 01:35 PM
Been doing research on wheels and tires. Here is my summary of many researched posts and articles, please let me know if anything is missing or seems off. (BS = Backspacing)
HIGH PERFORMANCE (Widest you can go without mods, or maybe just fender rolling and/or trimming)
Front
18X8.5 5X4.75 5.25BS with 235/40-18
Conservative front width could be 8 inch with 4.75” backspacing. Aggressive tire could be 245/40, conservative is 225/40.
Rear
18X9.5 5X4.75 5.5BS with 275/40-18
Aggressive tire could be 285/40. Aspect could be 35 for lower ride and less chance of rubbing.
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HARDCORE TRACK USE (Requires major vehicle modifications like Aftermarket subframe or steering assembly and Mini-tub set-up)
Front
18X10 5X4.75 5.75BS with 275/35-18
Rear
18X12 5X4.75 5.5BS with 315/30-18
Conservative wheel would be 11.5 with 5" backspacing. Aggressive tire: 335/30 works for 1969 but more difficult for 67/68. Backspacing based on 56" WMS to WMS rear axle.
____
Thanks for the input. Hopefully this will save us all some time.
HIGH PERFORMANCE (Widest you can go without mods, or maybe just fender rolling and/or trimming)
Front
18X8.5 5X4.75 5.25BS with 235/40-18
Conservative front width could be 8 inch with 4.75” backspacing. Aggressive tire could be 245/40, conservative is 225/40.
Rear
18X9.5 5X4.75 5.5BS with 275/40-18
Aggressive tire could be 285/40. Aspect could be 35 for lower ride and less chance of rubbing.
____
HARDCORE TRACK USE (Requires major vehicle modifications like Aftermarket subframe or steering assembly and Mini-tub set-up)
Front
18X10 5X4.75 5.75BS with 275/35-18
Rear
18X12 5X4.75 5.5BS with 315/30-18
Conservative wheel would be 11.5 with 5" backspacing. Aggressive tire: 335/30 works for 1969 but more difficult for 67/68. Backspacing based on 56" WMS to WMS rear axle.
____
Thanks for the input. Hopefully this will save us all some time.