Wheel offset question

951mat · #1 (**permalink**) 06-11-2006, 08:04 PM

I'm looking for 17x9" track wheels for a lonestar. I have 3.75" from the hub face to the inside of the fender lip on the front of the car. If the wheel is
10" wide, I think I need +/- 6.25" backspace to clear easily. (10-6.25=3.75") Ford makes wheels in 5.98 and 6.12" backspace. 6.12 is close, but not quite. I think they would work well anyway w/ no rubbing.

My question is can a wheels backspace be machined to increase it ever so slighty by about an eight to a quarter inch? This would let me choose from a 5.98" backspace as well.

mat

jarendall · #2 (**permalink**) 06-12-2006, 12:05 PM

I have read posts where someone said that American Racing will build the Shelby Cobra wheels with the offset you want, all of these wheels are custom built, I think you have to contact them to order the wheels

Rick Parker · #3 (**permalink**) 06-12-2006, 12:16 PM

Yes, most can be machined a minor amount. Be aware of potential caliper interferance with the spokes with the finished item.

392cobra · #4 (**permalink**) 06-12-2006, 02:03 PM

What year is your LSC ? It makes a big difference on the rear.

there was a change in the frame.2002 will just,barely,accept a 6.25" backspace.

951mat · #5 (**permalink**) 06-12-2006, 02:32 PM

My car was built in 1999. My current rear wheel is 6.25" bs and is a 17x9x275. I assumed it clears easily, but hadn't looked too closely as I was more concerned about the fronts clearing the fender lip. I know 17x8s would be simpler up front, but I want to try 9s.

Is my math right regarding the backspace?

Mat

392cobra · #6 (**permalink**) 06-12-2006, 03:42 PM

The LSC I was writing about is a '99 as well.He had to notch his frame and wheelwell to get a 17x11 (315x35 tire) with 6.25" backspacing to fit.He could had done it without the frame work but he wanted the tire centered in the wheelwell. He had to shorten the 4-links as well.

As far as the front...Have you checked the clearances with the wheel turned lock to lock ? The tire loaded and unloaded ?

Front Side and Back Side Settings

Front side is the distance from the front edge of the wheel back to where it contacts the hub (or drum). Back side is the distance from the back edge of the wheel in to where the wheel contacts the hub (or drum). These two dimensions added together will be approximately 1" wider than the designated wheel width. Wheel width is measured at the tire bead seat and does not include the flanges where balance weights clip on.

Figuring the Offsets

The best way to figure out what front and back side settings to order for your car, is to follow these steps:

Install a mock up wheel and tire on the vehicle.
Analyze and measure how much you would like the tire to move out or back on the front side of the tire and write down the dimension.
Measure how much you would like to change the backside of the tire position. Write down that dimension.
Remove the wheel and tire from the vehicle.
Measure the front side setting of the mock up and add it to the change you earlier recorded.
Measure the back side setting (rim edge) of the mock up and add or subtract that dimension to the change you wanted. These final dimensions will tell you what front side and back side settings you will want on your new Team III Wheels.
A straight edge on the brake/hub face can also be used to measure clearances in the wheel house to give approximate front and back side dimensions. Don't forget tire bulge and tire-to-fender clearance. Contact Team III Wheels if you have further questions – (510) 895-8880.

951mat · #7 (**permalink**) 06-12-2006, 06:16 PM

I did go lock to lock on the ground and didn't see any problems w/ my 17x9 x 6.25 bs wheel. I'd like the 6.12" cobra wheel which I think would be slightly better.

Eventually I'll like a set of 17 x 10s x 295 probably for the street. Don't want to notch anything but I do want to center the wheel in the wheel well. Did you friend have to shorten the drive shaft too? Does lonestar have those shortened rear links, or do I have to do that myself. Looks to me like the axle has to move about 1.25 inches foward. This may be a winter time project.
Thanks for any help.

Mat

392cobra · #8 (**permalink**) 06-12-2006, 06:46 PM

Because of the rear part of the frame being redesigned,the links from the newer frames are too long as well.
He took them to a machine shop to be cut and tapped.Pretty cheap from what he said.
He did have to have the driveshaft shortened too. 1" I think.

After he got the axle squared in the chassis,I went over and set his pinion angle (very important) and the preload on the upper right link.

While he was at it he got rid of those piece of junk rod ends that LSC supplies.

He is a very happy camper with it.