ThirdPedalNirvana

I hope I'm not doubling up on threads here, but I couldn't find a thread dedicated to this topic. As you know, those of us with non GSL-SE 1st Gens have a rough time when it comes to wheel & tire options. Mazda's stock alloys are nice and light, but 185/70 R13 doesn't give you many tire options for street driving. The 4x110 bolt pattern is so uncommon that you're either stuck waiting for an old used set of rims on eBay or you have to get Konig Rewinds- Wheels which look at home on the curvy MX-5, but which look positively ugly (imo) on the origami styling of the FB.


Konig Rewinds on a Miata



Konig Rewinds on an FB


I've also been burned by aftermarket alloys before on my 300zx (bending), and though Konig is a well known brand, I was drawn to getting steel wheels. So, I took the advice of people on this site and called Diamond Racing. First, I learned that they won't make the less expensive SC Series wheel in 4x110, only the Pro Street series. OK, $90 a wheel isn't too bad, but after tax & Shipping its more like $140 a wheel, or roughly the same cost as Konig Rewind Alloys. Then I learned that the lead time is about 5 weeks.

Now, I fully understand that the customization options of the Diamond Racing wheels makes them attractive to people who want a really aggressive upgrade- wide tires, wide stance, negative offset, etc. But I was looking to maintain the stock +17mm offset, and I only wanted 15"x6" wheels, virtually the same tire width. Furthermore, the tires on my RX-7 (since I purchased it a few months ago) were absolute trash. 3 different models. I drove down a windy road (part of my commute) after it rained, and even though I was barely breaking 15mph, I had to choose between braking and steering, because I couldn't do both at the same time. Checking the tire sidewalls, I saw that my rear tires were manufactured in 2009 (8 years old) and the front tires were manufactured in 1998 (19 years old! 19! I was 7 years old when those tires were made! What?!?!). Since my 300zx has to go into the body shop to fix some deer-in-the-road related damage, I knew I couldn't wait 5 weeks for diamond racing wheels. So I did some research, talked to my tire shop, and I am proud to say that (at the cost of some extra unsprung weight) I now have a set of 195/55 R15 Hankook v2 concept2 H457's on my RX-7. And I did so by spending less than $100 per corner on wheels, without buying any used parts. Here's what I did:

(1) Buy a set of 4x110 to 4x100 wheel hub adapters from UsaAdapters on eBay for $150. They are made in the united states and seem to be of good quality. The adapter's inner diameter is 60mm, while the hub's diameter is 59.1mm, so its very nearly hubcentric. However, the mounting between the wheel and the adapter is lugcentric. I was concerned about this, but my tire shop said that as long as the adapter is hubcentric, it's fine. What you don't want is a lugcentric adapter or spacer. I will update this thread if I have any issues with the adapter.

Hubcentric Adapter


(2) Buy some low profile lug bolts. I got 20 12x1.5 bolts from LugNutGuys on eBay for $26. The low profile bolt head keeps the entire lug bolt inside the 25mm thickness of the adapter.


low profile lug bolt



Adapter installed on front hub with low profile lug bolts.


(3) Buy a set of 2005 Chevy Cobalt Rims. No, I'm not joking. The Chevrolet Cobalt from 2005-2010 and the Pontiac G5 from 2007-2010 used 15"x6" steel wheels with a 4x100 bolt pattern and a whopping +42mm of offset. Subtract the 25mm of hub adapter, and you're left with the OEM +17mm offset. And the best part? They are available new from Doorman (model 939-100) on Amazon with free shipping for just $44 each.


Doorman 939-100 Steel Wheel

(4) For GSL Models: Remove the rear brake rotor retention screws. Some manufacturer's use these, some don't. Frankly, I've never seen a good reason why the lug bolts or nuts on your car can't sufficiently hold the brake rotor onto the hub. In the case of the screws on my car, they stuck out from the hub face so the hub adapter wouldn't fit with them on. Installing the hub adapter with the low profile lug bolts secured the rear brake rotor to the hub just fine.

Rotor retention bolt holes circled in red

The bottom line cost is $352, or $88 per wheel, to get to 15x6 wheels which can be left bare or use any number of generic wheel covers. Are there better looking options in 15x6 4x100? Yes. Are there lighter options in 15x6 4x100? Yes. But value wise, this is hard to beat. And if you do bend a rim, you only have to spend $44 for a replacement.

Wheels & Tires on!

There are a huge smattering of tire options available for 15x6 wheels. If you want to maintain the same outer tire diameter, the closest you can get is 195/55 R15, but you can do 195/50 or 185/60 or a few others. I am thrilled with my Hankooks, but coming from 19 year old tires I'd probably be thrilled with the grip 4 oversized bagels would provide. I am known as someone who doesn't like too much grip (if you can't break it lose when you try to, what's the fun?) and the most aggressive tire I'd ever consider on an FB would be the BFGoodrich G-Force sport Comp 2, also available in 195/55.

I hope this helps someone on a budget who is looking for better tire options. If I knew I wanted to keep this car indefinitely, I'd probably be willing to find some lighter wheels. However, I'm anticipating that once I start a family, I will probably switch out my FB for a late gen RX-8, it's hard to justify dropping $800+ on rims.

Carl

iTrader: (2)

Looks nice. You can also go on Craigslist and buy a set of stock second gen miata wheels (alloy 15x6) for $75-$200. Or any other Miata/Honda wheels for that matter. 4x100 really does open things.

The pic is with the car on jackstands so way to much fender gap, but you get the idea.

DreamInRotary

iTrader: (49)

Interesting find! Gotta love those super positive offset wheels, but only when used with the proper spacers to push them out and away from the suspension.