An M.G. Locost Build
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July 24, 2017

Through some very clever financial trickery, the details of which we don't need to go into here, we managed to work out a way to buy new tires for the Locost. Which means the Mustang wheels are finally on the car, looking every bit as good as expected, and rolling in perfect circles at speeds the old Rostyles couldn't begin to approach without shaking the chassis like a giant paint mixer. While not quite a total transformation, as the wheels do nothing for the massive wind buffeting effected by the tiny flat windscreen, the car is definitely smoother and more comfortable to drive.

  Totally un-photoshopped Mustang wheels
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The difference isn't due just to the roundness of the wheels, but also to their weight. The wheel/tire combination knocks at least five unsprung pounds off each corner, which doesn't sound like a lot but you can't argue with the results. The difference is noticeable at all speeds, not just on the highway. Large bumps are less jarring, and small bumps feel like they're being absorbed. We think the improved ride alone justifies the cost of the wheels, but that's only part of the story. A minor part. The biggest improvement by far is the handling, and that's due entirely to the new tires.

The tires are Dunlop Direzza ZIIs, more commonly known in the performance tire community as Star Specs. For about the last half dozen years, the 200-treadwear Dunlops have been the tire to beat. Two or three other brands have come close, or actually beaten them, but Dunlop haven't been sitting on their hands all that time, either. The grip of these tires is phenomenal. Some kind of glue must be involved. If you push it, the tires will eventually start to slide, but not until you've reached the kind of g-forces that could cause an unwary passenger to lose consciousness.

Steering is more responsive with the Star Specs, and feels lighter as well, although we haven't checked the air pressure since we got the tires back from the tire store, so they could be a little high. If we were still driving on the Rostyles we could just wait a bit, since those wheels tended to lose air at a slow but predictable and linear rate. We're not sure about the alloys, but previous experience with modern wheels suggests they'll keep the same pressure forever. Which is okay with us. We like the steering feel and it's hard to imagine the grip could possibly get any better.

Modern tire treads not so good in the wet  
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For the past three years we've described the ride and handling of the Locost as 'vintage'. We thought it was just the nature of the car, being a 60-year old design with a basic suspension and a live rear axle. The car would execute a nice four-wheel drift through turns just like a classic sports car, but it always felt like it was skating, not hunkering down and gripping the way modern cars do. Push a Miata into a turn and it bites down hard, then grabs the road and powers out with a purpose. The Locost, quick as it was through the turns, never felt like that. It just skated.

Now it grips just like a Miata. Even the Locost brakes work better, not because we couldn't lock them up before, but because we could. Easily. In fact, it used to take careful modulation of the pedal to avoid a sliding stop, and the obnoxiously loud squealing that would go along with it. Now, at the point where the car would've started its slide on the old Rostyles, it just stops. Right there. No muss, no fuss, no drama. We think it might still be possible to lock up the new tires, but of course we have to keep in mind the g-forces. And the passengers. And consciousness.

The 50-series tires take away some of the vintage look of the car, but you can't have everything. The good news is, the car doesn't look quite as worn out as it did on the steel wheels. Three-plus years and 35,000 miles of hard driving has taken its toll on the paint, windscreen, grille, interior, and just about everything else on the car. Only the new Raydot mirrors and Mustang wheels keep it from looking like an old barn find. It might help if we washed the car more, but we've found that's only a temporary solution, lasting at best a few days to a week. So hardly worth it.

  Mustang wheels slightly in the slipstream
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The Mustang wheel offset is 17 mm less than the Rostyles. This looks okay up front, but the rear tires stick out a bit, coincidentally around 17 mm. When we first trimmed our rear fenders back in 2013, we couldn't decide if they should be 8-1/2" or 9" wide. So we went with 8-3/4". This turned out to be perfect for Rostyles, less so for anything wider. So the tires stick out a bit, although we'll live with it for now because making new fenders would be hard. Not that we couldn't do it, because we totally could, but then we'd have to paint them, and wait for the paint to dry. And pay for them.

We did have a slight hiccup with the Mustang wheels. The wheel company, which we'll leave unnamed for now but is legendary in the Mustang world, sent us three wheels with the correct bolt pattern, 4x4.5, and one with a slightly smaller pattern, 4x4.25. To correct this, we decided option number one should be to point out the oversight to the wheel company. However, after several attempts to contact them went unacknowledged, we decided instead to go with option number three— purchasing a fifth wheel— after option number two— judicious use of a rat-tail file— was rejected for safety reasons.

Spare tire wheel looks similar to road wheels  
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Now we have to decide what to do about the spare tire. The skinny Rostyle still looks pretty good back there, and could actually be used in an emergency, assuming we had the tools on hand to change a tire on the side of the road, which we don't. On the other hand, the slight amount of filing necessary to attach the mismatched wheel to the spare tire mount would not be a safety issue, since the wheel would never actually fit on any of the hubs. There would, however, be a cost issue, as another Dunlop tire would be needed. Which is why the skinny Rostyle looks pretty good back there.

As noted in our last episode, the parts car— our plucky 1970 MGB GT— needs tires. The Michelins on the car date back to the Reagan administration. As luck would have it, the old Locost tires are only three years old, and would bolt right on to the parts car. The only problem is, the Rostyles on the parts car have been professionally refurbished and powdercoated, and the Rostyles on the Locost haven't, professionally or otherwise. The difference is fairly obvious. Plus, the Rostyles on the GT seem to be quite a bit rounder, so we'd like to keep them. So we're not sure what to do there.

  Right bumper shim is practically invisible
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We did fix a few other items on the parts car, like the choke cable and the driver's side mirror. We also found the right rear bumper had been pushed in half an inch, which made removing the gas cap something of a challenge. We could've fixed it by replacing the bent bumper mount, but that would've taken money. Or we could've bent the mount back into shape, but that would've taken work. So instead we shimmed the mounting bolt, which was both free and easy since we already had something we could use as a shim— a large nut. The fix is well-disguised, so no one will ever know. And it's a parts car.

Because this isn't the best time of year to drive around in a closed car without air conditioning, we only run the occasional early-morning errand in the GT, and continue to rely on the Locost as our daily driver. With new wheels and tires it feels more like an actual car every day. It tracks better, self-corrects better, and the steering wheel doesn't vibrate loose in our hands on the freeway. So much smoother at all speeds, and now it really is as fast as it looks. If we think about it, this is the Locost we always dreamed about back when we started building the thing.


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