Need help with fitment

Looking to put 255/60 17 tires on my stock 1991 OCC. Want to maintain existing ride geometry and speedometer readings and don't want to use spacers or adapters. I came across these 17 x 8 wheels at Summit that seem to fit the bill. However, their fitment guide does not work for the OCC. Can a knowledgeable forum member look over the specs and tell me if they'll work for what I'm after? THX

https://www.summitracing.com/parts/brw-909s785345#overview

Not sure about the wheels, but a 255/60-17 tire works perfectly on ROH Impala SS clone wheels.

This tire's rolling radius is so close to the factory 15" setup that you won't see the difference on the speedometer.

Stock impala wheel has 5" backspacing. This one has 4.5" which will move the tire further inward which may give you a clearance problem on the springs or shocks. Take some measurements

The wheel has "0" offset. The OEM wheel for an Impala wheel has a "+6" offset. This will move the wheel 6 mm further out. It should still work, as long as you are not lowering the car (especially in the front). The tire will be very close to the inside of the fender on the rear. The Impala wheel is an 8.5 inch wide rim, so the difference will be about 1/4 inch a the sidewall. You can not use a spacer, because the spacer will make it closer to the body.

I believe the center bore is much larger than the stock wheels, and will make it difficult to center the wheel on the hub. You can get centering rings to match the hub and the wheel.

If you search for wheels that fit the Impala, you will find wheels that will be a direct fit.

Your choice will probably work fine, but you will have a track increase of 6 mm (1/4 inch) on each side, and your sidewall will be another inch or so closer to the body than a 225 tire on the stock 15X6 inch rim.

You can check here for fitment: http://www.rimsntires.com/specspro.jsp

Very helpful info, thanks to all. I have better than 2" of clearance to rear fender with stock tire/wheel combo. Will the new combo add 1/4 inch or add more than 1 3/4" , leaving just a 1/4"?

Also, will the tire center itself with the lugs or are the rings needed? Since the lug nuts are covered with this particular wheel, exposing the hub and rear drum doesn't matter from an appearance perspective.

You can try centering the wheel with the lugs, but it does not always work properly. I would suggest getting the rings to be safe. Not having the snug fit on the hub will also put higher (all) shear loads on the studs, instead of the axle hub.

The combination will add about 1 1/4 inch to the outside, and 3/4 inch to the inside. You should check the rear for lateral movement during cornering to be sure nothing touches. The bushings may be a little "loose" from wear, and age. The tire width at the sidewall is slightly more than the width of the tread. The rim will also allow the sidewall to balloon at different amounts for different width rims, and a taller tire will have slightly more of a balloon effect of the sidewall that is exaggerated with a wider rim.

Great point about loading. I will pursue a 3" center bore and use the 1991 Caprice as my search vehicle.

This forum has saved me beaucoup cash and possibly my neck. THX

I bought wheels here, and they were priced reasonably.:

https://www.bbwheelsonline.com