Trying on new shoes: Rota RKR

We got in some new wheels from our friends at Rota, and immediately installed them on our BRZ.  The Rota RKR has looks that remind me of the old-school RS Watanabe wheels from Japan, but the size is a thoroughly-modern 18" diameter, staggered with an 8.5" width in front and a 9.5" width for the back wheels.

We installed a take-off set of tires from my BMW 335i.  Those happen to be sizes 225/40R18 and 255/35R18.  They fit the car easily, without any rubbing.  If I was buying a brand-new set I'd probably go a bit wider, to a 265/35R18 in the back and a 245/35R18 in front.  I think those would fit without clearance problems.  The rear I'm sure is an easy fit.  The front might be a little tight to the strut -- the spring perch sometimes gets close to the tire when you start going to a wider size.  Nothing a small wheel spacer wouldn't take care of.

In fact, I am thinking I might try some slim spacers just to space this set out a few more millimeters.  There looks to be plenty of room to the fenders.  The +44 offset is a good bit more than most aftermarket wheels for this car, although I definite prefer higher offset to lower.  You can always space a wheel out using spacers.  There's no way to push a wheel in if the offset is too low.

As usual, we secured the wheels to the car with McGard SplineDrive lug nuts.

Weight on the wheels is 21.2 and 22.1 pounds for the 8.5" and 9.5" widths, respectively.  That's only a couple of pounds heavier than the stock 17x7" wheels (at 20.1 pounds).

The RKR comes in other colors, including black and "Hyper Blue," which is a very vivid deep blue color.  I thought the Hyper Black looked classy without being too loud, but I confess I'm curious to see what the blue wheel would look like on our car.

I think the BRZ with the RKR on it looks very nice.  The spoke design is simple and tasteful.  The wheels give it a little bit of a toy car look, which to me suits the fun character of the car.

Products mentioned in this post: Rota RKR wheels, McGard SplineDrive lug nuts.

"No Power" No More

For a while now I've been fielding questions about the Mach V BRZ's vanity plates, which have spelled out "NO POWER" since the car was new.  It started out as sort of an inside joke about the public reaction to the car's low engine output back when the BRZ/FR-S were first released.  But now the car is supercharged, and it seemed to make less and less sense over time, so we just got some new plates -- see the photo.  It's not super-creative, but Virginia has some of the cheapest vanity plate fees in the country, so if you have any better ideas, let us know and we'll change them up again.

That license plate is mounted on a new, revised Platypus tow hook mount from Craven Speed.  The new mount has a couple of improvements over the older one, including an angled plate to better match the bumper, and a full-size backing plate for the license plate.

I don't have many new modifications to report on the car, save for some very nice Superpro sway bars and Kartboy rear end links.  The Superpro bars installed easily, and the fatter diameter (I went with 20mm front and 18mm rear, compared with 19mm front and 14mm rear for the stock car) keeps the car flatter under cornering.  The Kartboy end links are easy to install and we know from experience on other Subaru applications that they are trouble-free over the long haul.  At this point we don't know of an aftermarket front end link for the BRZ/FR-S.

Other than that change, not much is new.  I drive the car two or three times a week, including lots of plain old commuting with lots of stop-and-go driving.  I continue to enjoy driving it -- the fun handling never gets old, and the Innovate supercharger has delivered reliable and trouble-free power for the past year.

In a previous blog post from last year I mentioned condensation on one of the rear tail lamps.  That lamp was replaced under warranty, but we hear that Subaru has stopped doing that since then.  Our lamps haven't taken on any water in the interim, so with any luck we won't have to worry about it again.

We do have some new Rota RK-R wheels waiting to be mounted up on the car, so when that's done and I've taken some photos I will post up again.

Products referenced in this post: Platypus tow hook license plate mount, Innovate supercharger kit, Superpro sway bars, Kartboy rear end links.

Winter 2014 Update

A couple of our fans have reminded me that it's been almost six months since I updated this blog, so here's a little run-down of what's new.

Bring it on

After running 255/40R17 Sumitomo HTR-Z tires through the warm months, I swapped back to the 215/45R17 Bridgestone Blizzak WS60 tires for the cold -- and boy has it been cold this winter!  With the winter tires, the BRZ has been a solid winter partner, with very good grip in the cold (sub-40 F temps) and wet.  On actual packed snow, the tires don't perform miracles -- this is a light rear-wheel-drive car, after all -- but we never worried about getting stuck or sliding off the road.  After experiencing the scary slithery feeling of driving this car with the stock Primacy tires in the snowy stuff, the winter tires are such a revelation.  I highly recommend them to anyone who lives in a place where it snows.

I had promised an update about tire sizes and different wheel fitment, so I'll get into that now.  First off, I am NOT in favor tire fitment solely for the purpose of appearance.  You might see this called "stance" or "stretch & poke" or other terms that basically imply pushing the wheels and tires out to as far (or farther) as they can go for the sake of looks.  What I am in favor of is larger tires for higher levels of grip.  More grip gives higher cornering speeds, better braking, and better control in all kinds of transitional maneuvers -- planned or otherwise.  I'm definitely not in favor of getting the tire to a point where it will damage the body (or worse) at full suspension compression.  If you can't use the car for its original purpose, what's the point of the whole exercise?

17x9" Mach V Awesome with 255/40R17

Note that for snow, you actually do NOT want wide tires.  Skinny tires will bite harder into the snow, whereas wider tires will tend to plane up on top and not grip.  What I'm talking about from here on out is warm-weather performance.

As I mentioned above, we've been running a 255/40R17 tire on a 17x9" +42 Mach V Awesome wheel at all four corners.  We also run Whiteline Com-C upper strut mounts, which give us extra camber by moving the entire top of the strut, rather than by moving the tire/wheel relative to the knuckle, lke eccentric bolts would do.  I mention this because a lot of BRZ/FR-S guys seem to run the eccentric bolts (or "crash bolts") to gain front camber, and this can lead to clearance problems as a wide wheel and tire can start to run into the spring perch on the OEM shock.

18x9.5" Mach V Wicked Awesome with 265/35R18

I also test fit some 18x9.5" +42 Wicked Awesome wheels with 265/35R18 tires.  This actually did fit okay in the back, but in the front the tire contacted the strut, so we had to use a 5mm spacer to get it to work.  With the 5mm spacer, the front tire was sticking out of the front body work, so without more camber I wouldn't advise running that size on the front of the car.

I could have put a 255/35R18 or 245/35R18 tire on the front 18x9.5" wheel, but those tire sizes would not be as wide as the wheel, and I'm really a big fan of having the right size tire for the wheel, and vice versa.  But if you DID want to run the 18x9.5" Wicked Awesome wheel on all four corners of your BRZ or FR-S, I'd probably do a 265/35R18 in back, and a 245/35R18 in front.

17" Awesome in front, 18" Wicked Awesome in back

Anyway, back to our fitment experiments:  Knowing that our slightly narrower 255/40R17 tire fit the front, I thought I might put the 17" wheels on the front with the 255/40R17, and the 18" with the 265/35R18 on the back.  Some sports cars (Acura NSX, Chevy Corvette) run a staggered front-back setup from the factory.  Why shouldn't we try it?  That actually fit pretty well, and the wheel size matched the tire size nicely.

Plenty of people run different tire widths on these cars front-to-back, but I haven't seen anyone else do two different wheel diameters.

One final question the fans asked me to address is gas mileage after installation of the Innovate supercharger kit.  On my daily commute, which is mixed driving, with a good amount of stop-and-go, I used to get as much as 28.5 mpg pre-supercharger.  Since the supercharger install, I have seen 26.5 mpg when I stayed out of boost as much as possible.  If I drive like a hooligan and flat-foot it every time I leave a stop light, I see more like 20 mpg.  (Of course, when I drove like a nut before the supercharger I would take a pretty big MPG hit, too.)  So basically, figure a 2 mpg penalty from the supercharger install -- a small price to pay for a 37% increase in horsepower!

Links: Mach V Awesome wheels, Mach V Wicked Awesome wheels, Innovate supercharger.