An M.G. Locost Build

October 6, 2015

Our two-year anniversary came and went with little fanfare. We actually didn't celebrate at all, and we doubt anyone else did either. Our first anniversary was a lot more exciting, mostly because we had no idea the car would last more than a couple of weeks. A whole year was fantastic. Now that the Locost is mostly sorted, two years seems like only a little more than one, and while there may be slightly more wear and tear on the car now, it's hardly enough to notice. Next year will be different, we think, because we've been putting off a lot of needed work this summer.

One thing we'd put off too long was doing something about our loud exhaust. You may recall our original plan was to weld a giant muffler in place of our puny toy muffler, but that would've cost money and taken a long time, two factors that combined to make the exhaust sound quieter than it actually was. So we decided instead to try an experiment. We would simply clamp an auxiliary muffler onto the end of the tailpipe, to see how it sounded. The auxiliary muffler would take less than an hour to install, so we'd be able to experience the quietness right away.

  Less-attractive exhaust modification
click to enlarge

The auxiliary muffler is called a SuperTrapp. We used to run them all the time on our M.G.s back in the 70s, long before they had the horrible reputation they do now. SuperTrapp mufflers work okay, but they are ugly. They looked better on our M.G.s, but only because they were mostly hidden under the car. There's no way to hide a SuperTrapp on a Locost, so it just sits there being ugly. However, because this was just an experiment, just to see how the car would sound, we decided we could ignore the muffler's grotesqueness, and hope no one else noticed.

The SuperTrapp actually took less than an hour to install, and afterwards the car was definitely quieter. It also felt faster, not because it was, but because we could put some weight on the throttle pedal without cringing. The SuperTrapp got rid of the raspy edge to the exhaust note, dropped the volume several decibels, and completely eliminated the horrible resonance we used to get between 2000 and 2500 RPMs. We always hated that noise. It sounded like the engine was coming apart, which it probably was, but we didn't need to be reminded of it.

Doesn't look any better installed  
click to enlarge

But there was another noise, too, a kind of metallic buzz. A SuperTrapp is made up of a lot of metal discs that could buzz, but ours were all clamped down tight, so it had to be something else. We don't think a giant muffler would buzz like that. It wasn't a sporty buzz, either, more like an old Toyota with a leaky manifold. We tried varying the number of metal discs on the muffler, but all that did was change the volume. The buzz was still there. It was impossible to ignore, although we thought we could live with it in exchange for the reduced noise.

Another thing we thought we could live with is cleaning the area around the muffler each time we took the car out for a drive. Exhaust from a SuperTrapp does not shoot neatly out the side of the car, where it can fall harmlessly to the road surface. It sprays in a circle around the circumference of the tailpipe, and actually a little back toward the car. The onrushing wind keeps most of this mess out of the cockpit, but deposits it instead on the side of the body and the rear fender. Even after a short two mile drive, the rear fender would be black with soot.

  Soot deposited by SuperTrapp after a short drive
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Still, driving a quiet Locost was kind of fun, so we decided to leave the SuperTrapp on there. We tuned out the Toyota buzz, cleaned the rear fender several times a day, and did our best to avoid looking at the ugly growth on the end of the tailpipe. We figured, what the heck, it's just temporary. Just an experiment. We could deal with it for another week or two. In the meantime we placed an order with Summit Racing for a giant muffler, and eagerly anticipated its arrival. Unfortunately, it got backordered. So maybe a little more than a week or two.

After just a few days, though, we were starting to get depressed. The muffler was looking worse than ever. The hose clamps holding it on were turning purple, half the paint on the muffler had peeled off, and we were quickly losing interest in cleaning the rear fender every half hour. Even the quietness was getting old. We had a situation at a stop light where we had to get the attention of the car in front of us. The horn is useless for this, but we could always depend on a sharp blip of the throttle to get the driver in front to check his mirrors. Not anymore.

Then last week we were driving up to Sacramento from the Bay Area, and we noticed the car suddenly got louder. We looked down at the exhaust, and wonder of wonders, the SuperTrapp was gone! Nothing but the stub of the tailpipe sticking out. Apparently, hose clamps are not the best in automotive exhaust applications. We decided it would be a bad idea to stop on the shoulder to run back and look for the muffler, in part because we were moving along at a good clip in heavy traffic, and mostly because we were thrilled to have our old car back.

Major improvement  
click to enlarge

We did have to do something about the tailpipe stub, however, so we invested $14.95 in a chrome tailpipe tip from O'Reilly Auto Parts, and rather than clamp it on, we bolted it to the stub, our faith in hose clamps having taken a recent turn for the worse. The bolts are mostly underneath the pipe, out of sight, although we did have an unsightly gap between the old tailpipe and the chrome, so we filled that with JB Weld and wrapped it with aluminum tape. It's not perfect, but the added bling looks good from more than ten feet away.

We still plan to weld on that giant muffler. It's bought and paid for, and we still think the car is a bit too loud. The giant muffler will work much the same as our current muffler, muting the engine and shooting exhaust harmlessly away from the side of the car. But we're probably not going to be in a big hurry to install it. Welding on a giant muffler is not as reversible as, say, clamping on a SuperTrapp, so however it ends up sounding, we'll have to live with it. Somehow I don't think we'll mind.


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