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- Jun 21, 2012
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- 4,878
A recent thread (now closed) brought back memories of the 1960s and the Beach Boys song Little Deuce Coupe. Part of the lyrics say "she purrs like a kitten 'til the lake pipes roar ... you don't know what I got." I dug the Beach Boys songs at the time but had no idea what lake pipes were. I also didn't know what a "little deuce coupe" was. Fortunately, I was enlisted in the U.S. Air Force at the time and shared a barracks room with a carrot-topped man from California. Robert Zinn, if you are still alive and are reading this, give me a call.
Bob may be the penultimate Californian, but back in those days, being a Californian was "a Good Thing." All the innovation seemed to come first from California, before finally reaching us clods in the Midwest a decade or so later. Bob was also a hot rod enthusiast, temporarily side-tracked from that hobby by being stationed in the northern peninsula of Michigan at a B-52H bomber base, where summer consisted of about two weeks in June and winter occupied the rest of the year. Not much opportunity for hot rod building or racing. So we spent a lot of our off-duty time together talking about cars.
It turns out that one of the best places to test-drive high-performance automobiles (hot rods included) is at the Bonneville Salt Flats in Utah, a natural dry-lake bed composed of compacted salt that is very flat. Now the problem with testing a hot rod at Bonneville is getting it there from California. If you have deep pockets, you just load it onto a trailer and cart it off to Utah. If your means are more modest, then you must drive your hot rod itself to the test site.
Tuning the exhaust of a high-performance engine is not a trivial task. The last thing you want to do is place a flow impediment in the exhaust path. A muffler is a flow impediment that makes the internal combustion engine exhaust quieter. Some muffler designs are more effective than others at quieting the exhaust noise, but all do so at the expense of creating back pressure in the engine exhaust manifold. It is better to just have a straight pipe from the exhaust manifold aimed toward the rear of the vehicle. Problem is, the vehicle is generally not "street legal" and is very noisy without an effective muffler. Add a catalytic converter and the back pressure increases too.
Hot rods and drag racing were popular activities in California (and other places, too) in the 1960s, and since performance is everything when racing, people would install "lake pipes" and "Y" splitters ahead of the muffler and exhaust pipe(s). One exhaust path was almost a direct shot from the exhaust manifold, through the "Y" splitter, to the lake pipes. The other exhaust path went through the other branch of the "Y" splitter to the muffler and tail pipe. The lake pipes had bolt-on caps at the ends to prevent exhaust from escaping during normal driving activities. This allowed the muffler to be effective when the lake pipes were capped. At the race track, these caps were easily removed to allow the exhaust free passage through the lake pipes. Needless to say, when the engine was 'revved up" the "lake pipes roared." The lake pipe name apparently came from the fact that in order to drive your hot rod from California to the Bonneville Lake Salt Flats, you needed to cap the "lake pipes" during the trip and take the caps off after you arrived.
So now fast forward to the 21st Century where electronics have virtually taken over control of the automobile. Wouldn't it be nice if that "Y" splitter on the exhaust manifold had some sort of flapper or diverter, controlled by an electric motor of course, to direct the exhaust gasses to either the muffler and tail pipe(s) or to the lake pipes? Then, without getting out of your car, you could flip a switch to go from a "street legal" hot rod to a "screamin' demon" hot rod? At the race track of course. Don't mess with that switch during normal driving on public roads!
So, I did a little research on lake pipe electric exhaust cutouts. Turns out these actually exist. They are a bit pricey, some upwards of a thousand bux. They all are bang-bang controls that move from one limit position to the other limit position, driven by a geared DC motor. One poster even modified an existing window motor to operate an exhaust cutout. They may also sense the increase in motor current to determine when each limit is reached, disabling power to the motor at each limit until the direction is reversed.
From further research at hot-rod forums, I found most opinions say the electric exhaust cutouts are invariably leaky and not worth the money. Gee, I wonder why they would be leaky? Poor design? Poor quality control? Poor selection of materials? Hot, corrosive, exhaust gases flowing through them causing deterioration of seals around the moving parts? All of the above?
A leaky exhaust system is an invitation to carbon monoxide poisoning. One poster on one hot rod forum opined that exhaust cutouts were illegal in California. I wouldn't know about that, but it seems pretty damned risky to fool around with a leaky ICE exhaust system. I can see why the other thread was closed. If I could afford a hot rod (maybe a little deuce coupe?), it would certainly have capped lake pipes. My wife probably wouldn't allow me to race it.
Uh, I think I explained the "why," but after due consideration I am not going to explain the "how." The OP of the other thread should probably take his problem to a hot rod forum.
Bob may be the penultimate Californian, but back in those days, being a Californian was "a Good Thing." All the innovation seemed to come first from California, before finally reaching us clods in the Midwest a decade or so later. Bob was also a hot rod enthusiast, temporarily side-tracked from that hobby by being stationed in the northern peninsula of Michigan at a B-52H bomber base, where summer consisted of about two weeks in June and winter occupied the rest of the year. Not much opportunity for hot rod building or racing. So we spent a lot of our off-duty time together talking about cars.
It turns out that one of the best places to test-drive high-performance automobiles (hot rods included) is at the Bonneville Salt Flats in Utah, a natural dry-lake bed composed of compacted salt that is very flat. Now the problem with testing a hot rod at Bonneville is getting it there from California. If you have deep pockets, you just load it onto a trailer and cart it off to Utah. If your means are more modest, then you must drive your hot rod itself to the test site.
Tuning the exhaust of a high-performance engine is not a trivial task. The last thing you want to do is place a flow impediment in the exhaust path. A muffler is a flow impediment that makes the internal combustion engine exhaust quieter. Some muffler designs are more effective than others at quieting the exhaust noise, but all do so at the expense of creating back pressure in the engine exhaust manifold. It is better to just have a straight pipe from the exhaust manifold aimed toward the rear of the vehicle. Problem is, the vehicle is generally not "street legal" and is very noisy without an effective muffler. Add a catalytic converter and the back pressure increases too.
Hot rods and drag racing were popular activities in California (and other places, too) in the 1960s, and since performance is everything when racing, people would install "lake pipes" and "Y" splitters ahead of the muffler and exhaust pipe(s). One exhaust path was almost a direct shot from the exhaust manifold, through the "Y" splitter, to the lake pipes. The other exhaust path went through the other branch of the "Y" splitter to the muffler and tail pipe. The lake pipes had bolt-on caps at the ends to prevent exhaust from escaping during normal driving activities. This allowed the muffler to be effective when the lake pipes were capped. At the race track, these caps were easily removed to allow the exhaust free passage through the lake pipes. Needless to say, when the engine was 'revved up" the "lake pipes roared." The lake pipe name apparently came from the fact that in order to drive your hot rod from California to the Bonneville Lake Salt Flats, you needed to cap the "lake pipes" during the trip and take the caps off after you arrived.
So now fast forward to the 21st Century where electronics have virtually taken over control of the automobile. Wouldn't it be nice if that "Y" splitter on the exhaust manifold had some sort of flapper or diverter, controlled by an electric motor of course, to direct the exhaust gasses to either the muffler and tail pipe(s) or to the lake pipes? Then, without getting out of your car, you could flip a switch to go from a "street legal" hot rod to a "screamin' demon" hot rod? At the race track of course. Don't mess with that switch during normal driving on public roads!
So, I did a little research on lake pipe electric exhaust cutouts. Turns out these actually exist. They are a bit pricey, some upwards of a thousand bux. They all are bang-bang controls that move from one limit position to the other limit position, driven by a geared DC motor. One poster even modified an existing window motor to operate an exhaust cutout. They may also sense the increase in motor current to determine when each limit is reached, disabling power to the motor at each limit until the direction is reversed.
From further research at hot-rod forums, I found most opinions say the electric exhaust cutouts are invariably leaky and not worth the money. Gee, I wonder why they would be leaky? Poor design? Poor quality control? Poor selection of materials? Hot, corrosive, exhaust gases flowing through them causing deterioration of seals around the moving parts? All of the above?
A leaky exhaust system is an invitation to carbon monoxide poisoning. One poster on one hot rod forum opined that exhaust cutouts were illegal in California. I wouldn't know about that, but it seems pretty damned risky to fool around with a leaky ICE exhaust system. I can see why the other thread was closed. If I could afford a hot rod (maybe a little deuce coupe?), it would certainly have capped lake pipes. My wife probably wouldn't allow me to race it.
Uh, I think I explained the "why," but after due consideration I am not going to explain the "how." The OP of the other thread should probably take his problem to a hot rod forum.