An M.G. Locost Build
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October 11, 2016
Little Locosts

With 2800 miles on our engine since the rebuild, it's running better than ever, spinning like a banshee to 6000 RPMS, even though we don't know what a banshee is, or whether or not they spin. In all of those miles we've purchased exactly four quarts of oil, for one oil change. There was a time, not so long ago, when four quarts of oil wouldn't last a week. And we didn't change the oil so much as burn it off. The last oil filter was on there for the better part of a year, not great for the engine but at least it was easy to read the dipstick. Except when the oil was so low it didn't register on the dipstick.

  Oil stop from July 2015, one of many
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For some reason we're having trouble remembering what it was like stopping for oil all the time. We must've added oil at least a couple of times a week, and it's hard to imagine what a chore that must've been. We're also pretty sure we stopped a lot during long drives to add oil, but we only recall a few of those times. We do remember we often had to add more than a quart—driving a couple of quarts low was okay with us—but sometimes two quarts wouldn't quite do it, leaving us a little short of the MIN mark. But that much oil on the dipstick was fat city in those days.

As a consequence of the new motor, freeway speeds have risen a bit. Any concerns we might've had for high-speed stability seem to be mostly unfounded. At 80 the suspension feels rock solid, or at least pebble solid. The car does get light on its feet above 80, but you can still steer, and any aerodynamic effects of the bodywork seem to be masked by the swirling turbulence extending hundreds of feet behind the car, and probably a dozen ahead. At those speeds you're basically pushing a flat board into the wind, except a flat board is likely more aerodynamic than our Locost.

Not actually going this fast  
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What we really like is that at speeds above 80 you can hit the gas and the car still accel­erates. We're not sure where it would top out, but redline in fourth gear is around 107 mph, and we have no doubt the car could at least reach the century mark. We do have some doubt that we could. 100 mph is fairly relaxing in a Miata, BMW, Toyota, or pretty much any modern car. Not so much in a Locost. At 90 the wind isn't just pushing the car around, it's pushing you around inside the car. You're just kind of hanging on. We don't imagine another 10 mph would improve things.

By today's standards our Locost may not be super fast, but back when Lotus Sevens roamed the Earth, the ability to reach 100 mph marked the difference between an ordinary sports car and a true high-performance sports car. Whether or not you could breathe at that speed was irrelevant. In those days, all top-down sports cars were windy, and therefore more fun at sixty mph than at higher speeds, so long as you knew you could reach those higher speeds when you had to, such as when another sports car happened along. We think by those standards we're fast enough.

A few weeks ago we broke another snap on our vinyl boot cover. Before we had a chance to fix it, another one broke. Clearly these snaps were never intended to be unsnapped on a regular basis, as the amount of force needed to expand the securing ring inside the snap body often exceeds the force needed to pull the snap head clean off. Unfortunately, we have to unsnap the boot cover every time we fill the car with gas, and it's always a challenge to leave the gas station with all of the snaps intact. We're thinking we possibly could've spent a little more money on snaps.

  High-priced snaps will never fail. Probably.
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Without those snaps, the back of the boot cover is free to flap around in the breeze. So we needed to fix it, and this time, rather than just replace our dime store snaps with more dime store snaps, we upgraded to genuine Tenax snaps, as found on the finest convertible tops and tonneau covers. Tenax snaps are the equivalent of the giant latches we installed on our new bonnet—possibly not as handsome, but with a positive catch and a bright future. Of course at $6 a pop we couldn't afford to replace them all, but we did finance the two that we have to unsnap to fill the car with gas.

With the engine, clutch, and boot cover all working, there's not much left to do on the Locost, so we started construction of the steel version of our junior-scale Locost, the one that debuted in wooden form at the Maker Faire last May. As usual, by 'starting' we mean we cut some tubes, i.e. marked some tubes for cutting, so we didn't get a lot done but we did make some progress on the front suspension spindles. These more or less duplicate the MGB spindles on the full-scale Locost, 'less' referring to a Heim joint at the top in place of the traditional British trunnion.

Tiny spindles recall historic M.G. technology  
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Welding the spindles was limited to attaching bushing tubes to the lower kingpin and to the square tube that keeps everything at the proper angles in the middle of the spindle. We're using actual bronze bushings in the spindles, not as many as we probably should, but it's a lightweight car and shouldn't see a top speed over 20 mph, except maybe on a hill. I'm sure it'll be fine. This isn't the first time we've welded round tubes to holes in flat metal, although you might not know it by looking at the spindles. Fortunately the angle grinder fixed the worst of it.

  Steel frame will look similar to wooden mockup
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We plan to cut some of the frame tubes this week and tack weld at least the bottom tubes. The junior frame doesn't have quite as many tubes as a full-scale Locost, but still close to 75, and most of them have to be welded at both ends, one edge at a time, and if you haven't been doing the math in your head, that's nearly 600 welds altogether, more than a weekend job. Fortunately, the junior frame will be light, so we'll be able to build it on a flimsy card table, and when it comes time to do the final welding, we'll be able to flip it around with one hand. In theory.

Work on the junior Locost will continue where it doesn't interfere with work on the real Locost, and doesn't blow up the Locost budget, which is looking mighty slim these days after the engine refresh. We'll continue to report any progress on it, should any occur. If we manage to finish the frame, we'll start on the suspension A-arms, which if experience is any guide will take us well into the winter, and possibly beyond. But we're hoping the frame will be easy, so we're optimistic we'll have something we can roll around at the Maker Faire next May.


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