Well, in my never ending quest for dirt cheap wider wheels I wrote my yearly email to Diamond Racing Wheels. They still aren't doing the offsets we need, but they were prompt and very nice.

=====================
Aaron,
The maximum back space we make in the 15x7 4x130 is 4" or zero offset
because the center is dished backward like a regular RWD wheel.

Sorry but I don't think we will be able to help you.

Bill

On Wed, Mar 2, 2011 at 11:36 PM, Aaron McKinnon <mckinnon@caltech.edu> wrote:
> > I'm after a 15" rim, 7" wide, 4x130 bolt patter, 4-7/8" back spacing. I
> > could always add spacers if you can only do 5" back spacing. This is for a
> > narrow bodied Porsche 914 on DOT-R's in autocross. Car was the PCA CP class
> > winner last year and I'd like to take it up a notch.
> >
> > Let me know.
> >
> > Thanks.
> >
> > -Aaron

Diamond Racing wheels are heavy. We've got a set for our 24 Hours of Lemons Opel GT car in 15x7... they as tough as iron and every bit as heavy!

Got a photo?

I find it hard to believe that there isn't enough space on the barrel to slide the center out an inch.

Here's what I would do. Buy a set, grind the welds off the back of the center, build a jig to fix the center where I wanted it and reweld the center. There just steel wheels. I've done it before.

Sorry it was pre-internet and I have no photos.

Edit: I think I may have had to turn the wheel around, weld up the valve stem hole and re-drill the stem hole on the new outer side of the wheel.

I've got a set of stock 914 steelies I plan on doing this to if I can ever find wider hoops.

Back in the day (late 80's/Early 90's) we used to be able to purchase steel barrels with the centers unwelded. The local dirt track stock car guys had a source for these. I think I got a set once with wide 5 for VW. We built a wide body Ghia with VW headlights and used these wheels. I would check with the Dunebuggy shops to see if they have a source for these wide barrels with weld in centers. They will be for off road use.