17 inch tire sizes for 71 RR

I found some nice used wheels/tires for my 71 RR. My question is what size tires can I run on them...17x9 rear and 17x8 front. These tires are likely a bit small but will work for now.

I don't know your answer (somebody here probably does). There are charts online that show various tire's height + width. fyi-all 235/15's (for example) are really close in size, but vary slightly brand-to-brand.

Anyway...you can probably find out on this site what are the largest 15" tires that fit on a '71 with those width rims you have. Then, determine those tire's heights + widths from online 15" tire charts. Next, compare that height & width vs. online 17" tire charts and you will have your answer.

"Basically", the wheel well doesn't change (obviously), so you'll basically be putting the same "max" size tires on the car, but with shorter sidewalls (bigger wheel).

This site is my go too tool when I have customers wanting to change tire size. It will even give you speedo estimates of your going bigger or smaller

https://www.tacomaworld.com/tirecalc

Depending on offset 235/45 maybe 245/45 front. 295/40 possibly 305/45 rear. what sizes are on them now? Best way to determine is to look up the dimensions on the current tires and then get the total clearance you have with them mounted before interference( easier on rears). Than you can search on Summit site by tire dimensions.

Tires are 225/45/17 and 275/50/17.