Widest 17" Rear Wheel and Tire combo for 70 Cuda

[7Dcuda]

I did a search before posting this and couldn't find an answer for this exact question.  I'd like to know what is the widest 17" wheel width and the widest tire size that can be used on a stock 70 Cuda without having to do any alterations?  ...Anyone???
 

[73Chally]

Safest bet would be 8" or 9" wheels with 275 tires, but others have used bigger, up to 10" wheels and I believe 295 tires, but the lack of consistency in assembling the rearends and suspensions can cause some combos to work on some cars and not on others.  Your best bet is to get a tire fitment tool that will allow you to mount it on the hub and set whatever wheel/tire size you want, and spin it to check for clearance.  You want minimum 1/4" to 1/2" clearance around all components/wheel lips to allow for tire flex when driving.

[tommyg29]

I have a 71 cuda and a lot of my research tells me a 275/50 (of which there is little selection) or a 275/40 will fit with the right backspace. Some have claimed bigger, but 275 should fit most if not all cars. I have 5-3/8" clearance from the brake drum mounting surface to the closest point of the leafspring, so I'm going with a 4.5" backspace on a 17x9.5" torque thrust wheel

[Kapteenikosmos]

I have 17x9.5" with 5.5" backspacing on my 73 challenger. The tires are 275/50 (I only found two reasonable manufacturers for these, Nitto and Falken).

I have a standard width e-body rear with 1" spring relocation kit from Dr Diff. The perches were move inboard that one inch. I have plenty of room on the leaf spring side, something like an inch and a half or even more. On the fender side it's getting bit tight. The clearance between the lip is about one finger at max. I haven't driven the car yet so I cannot tell if it rubs or not with a load and while cornering, time will tell.

If it rubs, I'll put an b-body rear end under the car and it will solve that problem.