240Z / 260Z Offset and Wheel Pattern

[Ron Earp]

I'm not a wheel guru at all. I've simply purchased old wheels from David Spillman, Steve Parrish, and others to run my Z.

But, I'd like to get some new Spinwerks Z wheels in a 15" flavor. The car seems more predictable and happier with 15" wheels.

Spinwerks wants to know the wheel pattern and offset. I think the pattern is four on 113, but does anyone know what offset I need for the wheels?

Thanks,
Ron

[pballance]

4 x 114.3 spacing. 4.5" backspace . IIRC that = 0" offset.

[Ron Earp]

Oppps, meant 114 - had it right at Daytona when someone asked....

4.5" backspace? How wide of a wheel do you have?

[pballance]

7" as I recall......

I also use spacers in the front but I will have to measure them.

[mom'sZ]

Paul: I think (according to a chart I have) that a 4.5" backspace would be +12 offset on a 7" wheel. I have 4" backspace on my 15" x 7" wheels and that is 0 offset. They stick out kind of far but are still legal (not past fender lip). On my 280 with 15"s I'm pretty sure I have room front and back to fit 4.5" backspace wheels, which would tuck them up under the fender lips more, but I've heard track width is important for the front in terms of Zcar handling. That the more front track width you run the better the car handles. Spacers on the front would / could be a good tuning tool. here is the web site that I got the offset - backspacing chart from
https://www.rsracing.com/tech-wheel.html
Edit: I thought I should just add that I think most Zcar racers run the 4.5" backspace.

[betamotorsports]

4.5" of backspace is good. It lets you run wider spacers in front.