smparr

Once again, my rear left wheel cover came loose, jammed in the skirt, and then flew off on the highway before I could pull over! Luckily it did not damage the skirt and the valve stem, and I was able to pull off and recover it. I currently have a set of 1978 98 Wire Covers on it because the originals clicked and rattled, and I actually like the wire look. (I have the nice originals in a box in the attic. One of those had also flown off once too, by the way!) I've never had an issue with the other three. I kind of want to replace the steelies and covers with wheels anyway. Are there any actual wire wheels or Chrome Wheels that fit the '70 98's? I saw the 71-72 polycast SS IVs, but finding a decent set is a pipe dream. Would the later 77-85 Delta 88 chrome wheels or 1965-76 Buick 5 spokes work on a '70 98? Or maybe the Coker Wires for Cadillac and Buick? I'm know the stock steelies are 15"X6"/5"X5"'s. I'm not sure of the backspacing. I'm open to any suggestions that are stock sized, just tired of chasing wheel covers down the road.

Thanks,
Steve

joe_padavano

Your car uses a 5 x 5" wheel bolt pattern. Offset (not backspacing) needs to be as close to zero as possible. Backspacing to achieve that will depend on wheel width. I've got 15x7 with -0.25" offset on the front and 15x8.5 with -1" offset on the back of my 1967 Delta 88, only because the American Racing TTO wheels I wanted didn't come in zero offset. They fit fine.

smparr

So, would a 15x6 wheel with 3" backspace be the same as Zero offset?

OLDSter Ralph

Does this help ?

joe_padavano

Perfect diagram. Note that the lip thickness is added to the backspacing, so a 6" wide wheel with zero offset would have about 3.25" to 3.5" backspace, depending on the wheel material and lip configuration (aluminum wheels tend to have thicker lips than do steel).

smparr

Okay, so they aren't necessarily equal. Thank you, the picture does help.

OLDSter Ralph

That diagram is clear and makes sense of things. Keep in mind that tires will be wider at their widest spot, so the Backspace measurement is merely a reference, as far as I am concerned.
Save the diagram on your computer for further use.

Olds64

Don't forget to consider center bore diameter and center cap depth if you buy aftermarket wheels. I called Cragar to ask about these dimensions on a set of wheels I was considering for my 71 98 and they refused to provide me with these measurements. So I bought a different brand of wheel.

If you want wire rims or knock-offs then you should check out Tru Spoke:

https://www.truespoke.com/

joe_padavano

Most aftermarket wheels are lug-centric and come with oversize center bores to enable them to fit a wide variety of models.

Olds64

Good point; however, it's too easy to measure twice before spending money on wheels that may not fit. Especially if you spend $1000+ per Dayton wheel.

smparr

Has anyone tried a five spoke road wheel from a 1970 Buick Electra? They should be the same right?

joe_padavano

Lots of people have used them. Olds centers bolt right on. Unfortunately, they still look like Buick wheels.

smparr

I know they still look like Buick wheels but they don't fly off! Well, unless something goes horribly wrong. LOL

smparr

Joe, Which Olds centers bolt right on? SSI, SSII, or SSIII?

smparr

I went over to the Buick forum and now I'm more confused. Pre 1971 15x6/5x5 road wheels have a register ring that makes a 2 3/4" hub opening, 1971-80 does not have a ring and is 3". The stock steel wheels on the 98 right now have a 3" opening for the rotor/drum hubs. Does that mean Olds used a 3" hub size for big cars in 70?