Rear end width

llama man · #1 (**permalink**) 02-13-2007, 05:53 PM

I have a stock-width Ford 9" rear end that I need to narrowed down. I will be running Halibrand Cobra II 9 1/2" wide rear wheels with adapter plates for pins. What is the optimal width overall - to the outside of the tire - to fit the wheel wells? Given that dimension I will be able to cut down the axles and housing to fit.
Thanks in advance.

Rick Parker · #2 (**permalink**) 02-13-2007, 08:47 PM

Do you have the Cobra Body? Do you have the wheels and tires?
One way to determine the length is to put the tires on the rims and put them in the wheel wells (without axle assy in vehicle), adjust each one, be sure it is vertical and then measure the distance from the mounting surfaces of the wheels from side to side. Then go to one of the axle manufacturer sites and apply the formula shown to determine YOUR finished dimension. Like this:http://www.currieenterprises.com/ces...mrearends.aspx
The maker of your body/kit may be able to provide the dimension for you based on their recommended tire sizing. The finished length will vary depending on wheel offset.

496fe · #3 (**permalink**) 02-13-2007, 10:49 PM

Better still - if you already have the wheels, pin-drive adaptors, and brakes, bolt it all to the wheels. Then set the wheels where you like in the wells and measure what would be flange to flange.

Take your time now. The B&B body is a Street body, which is narrower than the Comp or SC bodies.

My rear end was 50" flange to flange with pin-drive Vintage Wheels, but I had them widened so they look much deeper than stock. The Vintage Wheels website has helpful info also.

The bigger challenge is the front end if you are going to use pin drives. Again, the B&B body is quite narrow and Mustang II suspension is quite wide. I can show you how to make the front track narrower if you like. I think it is worth the work because the B&B body is a good shape.

Clois Harlan · #4 (**permalink**) 02-14-2007, 07:07 AM

I just measured all that this weekend. If you have a 3 1/2" backspace on your rear wheels you will need a 50" (flange to flange) rearend. BUT, re-check your front wheels fit inside your wheel wells. Mine stuck out a full 2" with either Trigo or Vintage knock offs. The fix is to buy $2000 worth of custom spindles and brakes from Cobraracing in Torance, CA or cut your upper and lower A Arms. I narrowed my rearend to 49 1/2" and the Vintage Wheels fit perfect on the rears. No such luck on the fronts with any of the available knock offs.

Clois