67 Camaro rear diff help

[gixxer1k]

I'm ready to order a rear diff for my car. I have a 67 Camaro with dse mini tub. How wide should I go to install rims with a nice size lip? Should I measure from the face of the brake rotor. Thanks for your help

[exwestracer]

You cannot figure this out without knowing the size tire and wheel width you are going to run...

Start with the left to right fender lip width. This can be found by hanging a plumb bob from the fender lip pinch weld and making a mark on the floor. Do the same thing on the other side and measure in between the marks. It's probably somewhere in the neighborhood of 70".

Subtract 3" (1 1/2 per side) for outside tire clearance (note: you may need a lot more, depending on tire diameter). This will be the tire "bulge to bulge" width. Once you know the wheel width and offset you want to run, subtract the outer dimension of the wheels.

Let's say you have an 12" wide tire, a 10" wheel, and the offset is +1"... That means from the outside bead of the rim, the bolt face is 4" in. WHEW!

OK, so if we start with 70" available space, subtract clearance (3"total) we are at 67" tire bulge to bulge.

Then subtract the 1" from the tire bulge to rim bead and the 4" outer wheel dimension. That's 5" each side or 10" total, so your rotor face to face dimension on the rear axle would be 57".

Obviously, you need to figure all this out for YOUR car, and YOUR tire/wheel combo...but that's it in a nutshell. Don't forget to check if the tire will FIT all the way out in the fender opening.

[neki67]

http://www.rimsntires.com/specs.jsp

[TheJDMan]

I recommend you buy your wheels/tires first then order the rear end to fit the wheels the way you want them to fit the car. I have DSE mini-tubs and I'm running 18x12 Forgeline rear wheels with 335 tires. I purchased the wheels and tires first then mocked them up under the car to determine the exact width I needed. I ended up with a 57" wheel mount to wheel mount rear end housing. You can do all the funny measuring but you will likely not end up with as nice a fit as you would buying the wheels/tires first.

[exwestracer]

IMO, those 18s are perfect on a 1st gen... Nice car, Steve.

[TheJDMan]

Thanks Ray,
Your opinion means a lot to me!