Paranoid about wheel size

[cwilson]

I know I'm probably over analyzing this, but according to A&C, the recommended sizes for the wheels are as follows:

Front: 15x8 4.5" backspacing
Rear: 15x10 4" backspacing

I saw in an old post that someone was running 15x7 3.75" backspacing and said that the tire/wheel combo stuck out about .5". On the rear he was running 15x10 3.75" and the wheel was tucked under about .5". I may be having trouble with my addition/subtraction, but shouldn't the opposite be true.

The reason I'm wondering is that I ordered a set based on the recommended setting, but was told the best that could be done for the front was 4.25" backspacing, which would push the wheel out .25". This didn't seem like a big deal to me until I looked at the above wheel sizes. If a 15x7 3.75" sticks out .5", wouldn't a 15x8 4.5 stick out .75" and a 4.25" backspacing stick out 1".

Am I calculating something wrong? Maybe in misunderstood the original post.

[blykins]

You got it backwards.

The more backspace you have, the more the wheel will be tucked under the fender well.

The backspace is the distance from the rear rim of the wheel to the mounting flange. If you increase that distance, you decrease the distance from the mounting flange to the front rim because the overall width of the wheel stays constant.

[blykins]

This may help you a little bit.....

[blykins]

Remember, a 9.5" wheel is actually around 10.5" wide at its widest points. The more backspace you have, the less of a front "dish" the wheel will have. Inversely, the less backspace you have, the deeper the wheel will look, but the further it will stick out from the axle flange.

I went through all of this before when ordering my wheels. I wanted knockoffs, but the backspaces that were available would still make them stick out past my fenders...

I went with a PSE wheel....15x9.5 with a 4.5" backspace.

Check out this post for pics.

http://www.clubcobra.com/forums/show...ght=PSE+wheels

[cwilson]

I agree with you. That is how I thought it should work. What was causing my confusion is the post that referenced the 15x7 3.75" and 15x10 3.75" that seemed to contradict what I thought and what you said. Thanks, I'll rest easier, a quarter inch should make too much difference.

[Roscoe]

I have PSE GT 40 wheels, 15 x 7.5 with 4.5 backspacing and 15 x 9.5 with 4" backspacing. I did have a small issue with the drivers side rear slightly rubbing on hard turns. I installed a 1/4" spacer and that was that.

Roscoe