View Full Version : Track width ratios and their impact

09-13-2004, 10:08 PM
Today as I sat at the shell station filling up the chevelle I started wondering about the impact that taking out 1/8" of backspace per side on my rear rims would have on the handling characteristics of the car.

Tommorow I will mesure the front and rear track widths to provide some numbers for us to work with.

The reason for having the backspace changed is because I have more clearance to the outside then the inside and I am already running a 1/8" spacer. I plan on having the centers cut loose and re-welded with 1/4" less back space and then remove the spacers, but if there is an advantage to going more or less then I would consider doing so.

Anyhow just thought that I would throw it out there and see what you guys think. Seems to me that having a wider track in front would be the desirable situation, the questions is by how much.

For referance the car is on a 115" wheelbase. 1966 Malibu.

09-14-2004, 10:30 PM

09-14-2004, 11:16 PM
I have to write down an answer so I don't sound stupid. Give me a few days. I'm really slow....... :geek: Otherwise, I would have answered already. I do have an answer though. It may not be right, but it's an answer....

Oh yeah, why are you running the spacer, anyway? Is this on just the front? Or the rear as well?

09-15-2004, 07:24 AM
just in the rear, my rims have more backspace then I need.

Salt Racer
09-15-2004, 08:01 AM
I agree that front track should be slightly wider than rear for stability reason. But that's in ideal cases and/or open-wheel race cars.

There's only so much you can do with street-driven lowered closed-wheel cars, unless you flare the fenders or raise the wheel openings. I'd make the track as wide as you can go. Less the lateral load transfer, greater the lateral traction potential. Then balance out the handling with spring/sta bar rate.

09-15-2004, 08:20 AM
Umm... what he said.....

David Pozzi
09-18-2004, 08:21 PM
In general, wider track is better, it lessens weight transfer to the outside wheel, BUT 1/8" is not going to make any difference, I think you'd have to change track width by almost an inch per side to do anything noticeable, and even then you might not notice any significant difference.

Too much offset on the front can cause steering problems and the tire moves too much front to rear when turning causing kickback and rubbing problems.

Salt Racer
09-19-2004, 03:02 PM
David is correct. What I said was in regard to rear track width. Up front, I wouldn't consider using negative offset (ie, shallow BS) rims. I'll stick with neutral, or better yet, positive offset wheels to minimize scrub radius.

I checked the effect of 1/8" per side track increase on my spread sheet. As David suggested, it really doesn't have much effect (like 3 lbs reduction in lateral weight transfer). But I'd still make the rear track as wide as you can if you have to re-hoop the rims for some reasons. Every little bit counts.