Yes, it’s possible. Yes, I run winter beater steelies on my 2007 STi Limted. Yes, they’re ugly. And yes, this post has all of the details, with pictures.

Why?

Some will say that all Subaru vehicles handle great in the snow with just all-season tires. And I would, in general, agree with them. But if you want superior traction and control in the snow, it’s no secret that Subaru’s incredible symmetric all-wheel-drive is enough. When it comes down to it, you need great tread if you want great performance.

When I bought my car it was equipped with 225/45/17 Pirelli P-Zero Nero Mud and Snow tires mounted on 7.5″ wide heavy-as-anything rims. I don’t know if it was something about that set of tires in particular, but I was sliding around all over the place in just a few inches of snow. Needless to say, I expected better traction than that. A friend of mine with a rear-wheel-drive Volvo on two snow tires said his traction was better than what I was getting with my STi. I believe him.

But why, then, should I get a separate set of wheels? Of course, there’s the usual argument that it’s much easier and more convenient to be able to quickly switch tires without having to dismount/remount at each season change, but there was another reason that struck my fancy: performance. I wanted to get as narrow a wheel as possible, and found the answer in steel wheels. I have yet to find an alloy wheel as narrow as the steelies I use now while still fitting over the Brembo brakes¹. Now, I have wonderfully narrow wheels for the winter and sweet wide wheels for the summer. It’s the best of both worlds.

Wheels: 2007-2009 Honda CR-V Steel Wheels

I found a forum post on iwsti.com about 6.5″ wide steel wheels that fit over the Brembo brakes on the STi. Let’s review the benefits, here: cheap, great fitment, really narrow, and again, cheap. I was totally sold on it. For $180 I had four brand new take-offs shipped to my door². Test fitment was absolutely perfect, with a whole lot more room between the wheel and the brakes as compared to any other wheel I’ve seen on the STi.

The 2007-2009 Honda CR-V steel wheels are 6.5″ wide, 17″ in diameter and have an offset large enough to fit over the stock Brembo brakes on any year STi. The bolt pattern on these wheels is 5×114.3, so they should fit on any STi, model year 2005 and up at time of writing. I did not use hub-centric rings and haven’t had any balance issues so far. As noted elsewhere, you should always use ball-seat lug nuts with Honda wheels. Stock subaru lug nuts are of the conical seat variety and matching lug nuts and wheels correctly is pretty important if you want to avoid having your lug nuts loosen and your wheels fall off.

The only major issue with these wheels, apart from the fact that they’re ridiculously heavy compared to a decent set of alloy wheels and that they’re ugly as sin, is that the stock center caps are embossed with a Honda logo. Since I’m not the kind of guy who likes to run wheels without center caps, I decided to remedy the situation a-la-DIY. What I came up with was a solution involving sanding³, Bondo, more sanding, priming, even more sanding and then painting⁴. Pictures below illustrate some of the process.

Tires: Dunlop WinterSport 3D

I decided to spring for the Dunlop WinterSport 3D wheels in 205/55/17. For winter performance I wanted the extra sidewall height and of course went as narrow as possible. It’s my understanding that Dunlop (or anyone, for that matter) doesn’t make a 17″ tire narrower than 205. Just the same, I’m not sure how going narrower than 205 would affect handling at highway speeds — I certainly did notice a subtle difference going from 225 to 205, especially in tracking at higher speed.

Results

The difference in traction and control between my new winter setup and my old all-season setup is enormous. Having never run winter tires before, I had no idea that the difference in handling and confidence was so night-and-day; had I known, I’d probably have made the switch many years prior.

My ‘custom’ center caps have held up pretty well, considering it was a makeshift rattle-can job. The paint hasn’t peeled or chipped, nor has the Bondo. All-in-all I’m very satisfied with the results, even if they’re ugly. As usual, I go for performance over looks!

1. Even if there were such a wheel, I doubt it’d be as cost effective.
2. Thanks to eBay.
3. Always roughen smooth surfaces before applying Bondo.
4. Actually, there were several rounds to the priming/sanding/painting routine.

Dissection

I needed to find out exactly what I was working with, so I figured the best way was to actually remove the stereo head unit itself and see what ports are available in the back. In the best case, there is an auxiliary input port. In the worst case, there is no extra port at all. I expected there to be at least an external CD changer port.

I found a great guide for the removal of stereo head units for my car. Actually, it’s a guide for a Subaru Outback 2001, but the dash setup is exactly the same for the 2003 Legacy [wagon]. With the excellent directions and illustrations on said guide, I was able to dismantle the necessary parts and extract the head unit within a half hour, having had zero experience in the area.

Research

Once I had the head unit in my hands, I was able to take a look at what was in the back of it, and see what my options for an iPod hookup were.

Needless to say, there was no auxiliary input jack. As expected, however, there was an external CD changer port on there. After having done some research online, I found that this was absolutely useless to me. The 16-pin port I found is proprietary and has not been reverse engineered as far as I can tell. There are no after-market auxiliary input adaptors for this type of port available at time of writing.

Back to the drawing board. I had to find out what other options I had. I knew all about the wireless FM transmitters on the market, and had read a good number of reviews on various makes and models. There was no way I wanted to deal with any sort of interference or quality loss, especially expecting to be in the Boston metropolitan area as much as I do.

It looked like my only options for wiring in directly to the audio system in the Subaru was to either replace the head unit with one that has an auxiliary input jack, or use a wired FM modulator. I settled on the FM modulator.

How It Works

The small device I ordered online for $25 does the same thing as wireless FM transmitters — that is, converts an input audio signal (say, from an iPod) into an FM radio signal that any radio tuner can tune in to — except that this one sits in between the aerial antenna and the head unit, so that the signal is not broadcast via air but rather wired directly into the antenna port of the head unit.

The idea here is that, since the wired FM modulator sits in between the antenna and the head unit, it is able to directly inject the modulated FM signal into the head unit’s antenna feed, rather than adding to the already existing signals in the air. An on/off switch connected to the modulator allows for selection between the antenna and the modulated signal.

Installation

In order to get it all working, three essential connections had to be made. (1) Power was drawn via a direct connection to the rear plugs on the car’s stock 12V electrical outlet. The (2) Antenna lead was removed from the back of the head unit and plugged into the FM modulator. The (3) Head Unit connected directly to the FM modulator via the head unit’s antenna port.

Lastly, the Power Switch and Audio Leads were routed through the front dash area via a small space underneath the ashtray. With everything nicely in place, I was able to stow the modulator box itself right next to the shift lever — Subaru nicely left a couple of inches on all sides of the shift lever housing. There was no need to cut any holes!

No visible changes were made to the car, excepting an audio lead hanging out from underneath the ashtray, which can be neatly stowed away out of sight when not in use. The on/off switch for the modulator fit nicely underneath the ash tray, completely invisible to passengers and driver alike. Since the whole setup is transparent, not only does the car look as great as it ever did, but it’s also not any more subject to theft.

Results

The sound quality of the setup isn’t quite CD quality by any means, but it’s good enough for the average Joe not to notice any drastic difference. Since the rest of the audio equipment in my car is stock, I can’t really justify putting any additional money into a higher-quality setup for auxiliary input.

In order to reach some level of satisfaction (I’m a picky customer), I had to play with the gain adjustment on the FM modulator. With higher gain comes higher volume but also some distortion. Lower gain yields lower volume but less (or no audible) distortion. I found that once I turned off the ‘Sound Check’ (volume normalization) feature on the iPod, I was able to lower the gain substantially without killing off the volume. Now at a medium-high volume output on the iPod, the FM signal from the modulator is the same volume as an average radio station.

There is one quirk with the setup. Whenever I turn the FM modulator on, and tune it to the station that I set it to modulate on — 88.7 — it takes a few seconds for the modulation to start up. More interestingly, when it does start up, I get a strange shwaap out of the speakers before the silence (or audio from the input signal) kicks in. I’ve grown to kind-of like the satisfying sound, as it helps me recognize when the modulator has just been turned on.

Verdict

All in all, I’m happy to say that I’m a very satisfied customer, and would recommend this setup to anyone willing to rip apart their dash in order to do the installation. Since it’s wired, it shouldn’t be possible to really inject any noise or interference in the line, assuming that all connections are properly insulated. As such, I haven’t experienced any troubling interference on the line (there is a slight hiss if you broadcast silence and turn the head unit’s volume all the way up).

In my opinion, this is a success story.