I am looking at buying some slotted mag wheels from a seller on the DPAN FB page.  He has provided the pictures below and has said they are 15x7.  It has always been my understanding and various wheel sites have shown that the true diameter of a wheel is the measurement of the rim itself.  Basically the wheel minus the raised lips for the tire bead or to look at it another way, the diameter of the hole of the tire that will fit on the wheel.  He shows an overall 15.25" diameter with a lip height of .75".  The math would work out to .75 X 2 = 1.5.  15.25 - 1.5 = 14.75.

When I measure the 14 x 5.5 wheels currently on my 240z, they have an edge to edge measurement of 15.25 as well.  So my question is this, is the wheel in the picture a 15 inch wheel or a 14 inch wheel?  

14".  Your assumptions are correct. What brand are they? Ansen Sprints?

He has not been able to find a manufacturer's mark or name cast or stamped in the aluminum.  The only items he has found so far is an inspector label. It indicates the name "H. Sugiyama" and the numbers 9 11 stamped in to the hub mounting surface on the back.

You may find more markings after cleaning the backside. They should look good after cleaning and polishing. I've always like the "look" of slotted wheels. 

Those are 14x7.

 

Thanks for all the info guys!  Glad I posted this up before I sent any money.  Since I already have a nice set of 14x5.5 slots on my 240z, I don't see the need to pick up a set of 14x7's right now.  If they were 15x7's I would be all over them as I have been looking for a set forever.  If anyone is interested in these you can look up Chris Caiazzi on FB.  These were posted on the DPAN FB page and the 240z 260z 280z Lovers page.

Glad you didn't spend money on that. I've been through the same thing with other people selling used wheels. Many people don't know how to measure them and advertise incorrect sizes.

The width is measured on the inside of the wheel where the tire bead seals to the rim. In general, the wheel lip thickness is "about" a half inch thick per side, so even if the only measurement you have access to is the outside dimension, you can usually infer about an inch narrower than that because of the lip thickness.

And as for the height... I use the middle of the lip where the tire bead makes contact. I'm not positive if that's the official measurement location or it it's really supposed to be the diameter of the hole in the center as you said, but those two locations result in measurements that are close enough that you can't make a mistake. The solutions are quantized.

are those wheels worth much? i have a set that are 14x6 that i am not going to use.

sorry for the hi jack

Well I'm no expert on the used wheel market, but since nobody else chimed in, I'll relay my experience.

I frequently see five slot wheels like that for maybe $200 or less for a set of four. Once or twice as low as $100 for a set. So it might be regional, but I think you could find (or sell) a decent (missing center caps, but no curb rash) set for around $200?

thanks