Miata wheel offset options?

I am on the cusp of "Hella-Flush" and fender flares.

Seeing as this is Miata suspension, how much wheel offset can I get away with if it means I can leave the tin alone?

Would a change from 205-55-16 to 205-50-16 help? The current 205-55-16 seems to overhang the rim quite a bit. (7" rim)

The common Miata widths of 7.5/+42 and 8/+36 clear stock suspension with no questions asked. So that's a backspacing of at least 5.4 inches that you can run without hitting anything inboard. My 7.5 inch wide wheels with a 205/50/15 tire mounted are right at 6 inches backspacing to the tire sidewall and don't rub anything. Closest point is front swaybar at full lock. What is your offset now?

I wonder if OEM ND wheels would help you since they are 4x100mm and have a high 55mm offset. And it looks like the base model has 6.5" wide wheels and runs 195 series tires, so that would help too.

I've never run anything higher than 38mm offset,7" wide on my NB, but that suggests you could easily go to a 6" wide wheel and 50 mm. (if I did that right) The inner edge of the wheel would be in the same place. The problem is going to be finding a wheel that fits and suits your eye. There are lots of 6.5" wheels around, but 38mm is pretty typical. Contact some of the WOSCA guys and see how a set of the Miata 16" wheels look and fit, or I could come up and you could try mine before the snow flies.

RedGT wrote: The common Miata widths of 7.5/+42 and 8/+36 clear stock suspension with no questions asked. So that's a backspacing of at least 5.4 inches that you can run without hitting anything inboard. My 7.5 inch wide wheels with a 205/50/15 tire mounted are right at 6 inches backspacing to the tire sidewall and don't rub anything. Closest point is front swaybar at full lock. What is your offset now?

And 9/36+ will rub the control arm (15" 6UL) before full lock. So the answer is probably somewhere between +36 9" and 8", converted to whatever width you intend to run.

A shorter tire would probably help. Why aren't you using 23" tires? They look to small in the wheel wells?

What is the offset of those wheels? Any reason you want 16"? 15" would at least give you more clearance. I have a set of OEM 14" wheels (I'm in london), but I don't have anything else of use.

What he said. I don't know the look you are going for, but if the above picture is at ride height, going to a 15" wheel with a 205/50 or 225/45 tire will shorten the tire diameter by 2" so you'd gain an inch of clearance to the wheel well. Combined with pulling the tire and wheel face in from the fender a bit with an offset change I think the look would work very well on an older body style car like that. This also lets you choose from 5,000 different 15" wheel widths and offsets.

Overall diameter has a big effect on the look of a car, I'd keep the big feets.

NA/NB Miatas can handle right about 6.25" of backspacing, BTW. The suggestion to look at ND wheels is a good one. Since that's a developing market, maybe you should put off the decision as late as possible in order to see what shows up.

Keith Tanner wrote: Overall diameter has a big effect on the look of a car, I'd keep the big feets. NA/NB Miatas can handle right about 6.25" of backspacing, BTW. The suggestion to look at ND wheels is a good one. Since that's a developing market, maybe you should put off the decision as late as possible in order to see what shows up.

Keith is right, I don't have to sort this today. But I do need to start looking for a solution for when I get there. Originally I did not object to the need to add fender flares, kinda figured it was a given. However, as I progress, and seeing as I am close to getting a tire under the Volvo, I have taken to the idea of preserving the P1800 body-lines. ( Could also just be I am getting tired of tin-work).

So, first things first, I need to figure out what the offset of these wheels have and go looking for an alternative with more offset Or is it less offset? I can never keep that bit straight.

I will post some pics of the car with a set of ROTAS that I had on the Protege. They are 15". I did try the Miata Daisys and they just looked dumb!

All else being equal, increasing the offset will increase the backspacing.

15" is what I would go for, with a similar sidewall to that picture. Tirerack has a pretty good selector for backspacing and such.

http://www.tirerack.com/wheels/results.jsp?&autoMake=Mazda&autoModel=Miata&autoYear=1996&autoModClar=

I would not go to a small overall diameter. The Volvo isn't designed around it.

Here's what happens when you bolt on undersized tires, visually.

Stock at stock ride height (24.3" OD)

Slightly oversize, lowered (25" OD)

Undersize, lowered (23" OD)

In reply to NOHOME:
Pete, the offset is normally cast into the hub area of the wheel. What brand are the wheels in your picture?

I just went out to the garage and measured the backspacing on two sets of wheels for my MINI. Both are 5.75 inches. The stock ones are 6.5x16, and my summer wheels are 7x16 Rota RBs. For what it's worth , I think a Volvo looks good on RBs, almost any car does. Tire Rack lists Miata and MINI wheels at the same offsets, but my stock MINI wheels have more back space than the stock Miata wheels. Some stock MINIs might set in a little more on your car.

That's photochopped!!!!1!1!11!!! Lol. Just kidding.

In reply to Keith Tanner:

I disagree some on the OD size. The 205/55-16 diameter essentially matches the OE tires for a 1800ES, which had 15" wheels stock. The "default" tires most 1800E & ES (those cars have slightly wider stock wheels than the earlier cars) owners buy is 195/65-15.

I've been involved with 1800's for awhile now. Most owners run stock wheels (they tend to be a stodgy bunch), but I'll admit few aftermarket wheels look "right" on an ES. BBS, Panasports, 240 Turbo... And can easily look cartoonish with anything 17" or larger. Even 17's are tricky. Volvo Pegasus wheels don't look bad. Personally, given the switch to 4x100 pattern, I'd probably go with Panasports.

Also bare in mind, the OE wheels are quite a bit more "inset" than current cars (the track is much more narrow). The fenders roll under the car in a more gradual way. If you want to run wheels that are closer to the edge of the fenders, you'll want to install some type of mud flap. Otherwise, normal road debris will beat the piss out of the paint in short order.

Ian - some of the guys here were suggesting Miata sizes of 205/50-15 or 195/50-15. That's considerably smaller than the 24.9" 205/55-16 you mentioned. It would look all kind of wrong.

I don't care about wheels, they're just the things that fill the hole in the middle of the tire. In this case, you need to nail the tire OD first, then figure out how much shiny you want in the middle of your rubber.

Sorry to hijack but what bbs wheel is that in the first post?

Keith Tanner wrote: Ian - some of the guys here were suggesting Miata sizes of 205/50-15 or 195/50-15. That's considerably smaller than the 24.9" 205/55-16 you mentioned. It would look all kind of wrong. I don't care about wheels, they're just the things that fill the hole in the middle of the tire. In this case, you need to nail the tire OD first, then figure out how much shiny you want in the middle of your rubber.

Am I the only guy that doesn't really like low-profile tires? I dig the meaty rubber look.

Stampie wrote: Sorry to hijack but what bbs wheel is that in the first post?

You mean this one?

Not sure of the exact model name, but if I Google BBS RS wheel it has some that look like it. I bought used of Kajiji with the main criteria being round 16" by 7" wide and 4x 100mm bolt pattern. Helps that I really liked the design and the brand.

BBS RX.

Cool thanks guys.

In reply to Keith Tanner:

OK - misunderstood your post.

Something to remember is he doesn't really need Miata sized tires. In theory, the torque from the SBF should easily turn a larger diameter tire. Plus, there is the effective torque multiplication of it being an automatic.

I have seen 195/60-15 tires fitted to an 1800. Those don't look too bad, although not my preference.