I am not sure about everyone else reading this, but I can recognize certain Alfas by the sound they make as they drive by. I remember when I worked at Garcia Alfa Racing I could tell if what just pulled up was an Alfa and also what model it was. For some reason a GTV6 was especially telling in its exhaust note.
There is something special about an old Alfas sound. Modern regular cars do not often share the same qualities. The best car I can think of for sound right now is perhaps an Infiniti or Nissan. They have spent countless hours tuning the exhaust to be just right. I must admit that I have added those vehicles to the list I can identify by sound. Of course I cannot tell one from the other but I can certainly give you a brand. Sadly their exhaust note just isn’t right. It sounds processed. It sounds contrived. It seems obvious they put the sound there. It did not come about naturally.
In an Alfa the sounds are there because they are meant to be there. I cannot speak for the new Alfas but the ones they sold in this country I know all about. Have you ever seen the inside of an Alfa exhaust? You want to know why they sound so good? The answer is two fold. First it is because performance was paramount. The second is because Alfa is cheap.
Performance comes from tuning the exhaust. A lot of people think that the key to exhaust performance is reducing backpressure. That is true but only up to a point. You see certain amounts of backpressure are key to low-end torque. But if you want top end power you have to find a balance and get that pipe as free flowing as possible. Well anyone can tell you our cars are not torque monsters. If you want some grunt you have to wind the stink out of them. Rev it up a bit. See how far you can bury the needle in the red before your ego gives out or the engine gives up.
So what is inside an Alfa exhaust that makes it so free flowing? The answer is nothing. Perhaps you have seen commercials for flowmaster or other fancy exhaust systems. They use baffles and the redirection of air flow to quiet things down while producing the desired sound. An Alfa exhaust is more like the silencer on a gun. Take a tube, put some perforations around it and put it in a box full of steel wool. You take out some of the sound but you leave most of the flow. The realities are somewhat more technical than this but you get the point. Other companies use weird contraptions to make their exhaust sound a certain way or to make their exhaust note just plain disappear. Alfa said screw your ears and get that gas out of the engine as fast as you can! The end result is a nice burble and an excellent noise response to your right foot.
The cheap aspect to the Alfa sound comes from the background of the company. No, not the background we read about in books with all the racing and engineering and design. I am talking about the lack of money, the poor craftsmanship of many of the parts, and the general cheapness of materials. I have a receipt for my spider that shows the original owner had to get a new exhaust for the car less than five years after the original purchase date. What? Five years?!?! That is absurd. But if you think about it, it all makes sense. If they made the exhaust out of thick, heavy gauge, high quality steel all the sound would be lost. Or perhaps the note would not be as sweet. Instead they cobbled together an ill-fitting exhaust using recycled rusty cans and left over pencil shavings. The welds cracked the moment your drove off the lot. The seams rusted out the first time your drove through a puddle. Sure the materials were awful, but nothing sounds better than metal so thin you can read through it. When the engine screams for more we can hear every last word!!
Now let us get away from exhaust for a minute. Why is everyone so obsessed with exhaust? I blame emissions and American V8s. People are obsessed with exhaust because they have forgotten what a proper intake noise sounds like. I mean seriously, which is better a nice exhaust or the snort a set of side draft webers makes as it tries to suck a small animal down into the engine? I think we will all agree the snort beats the fart any day. So where did the snort go? Well it got buried.
In the history of Alfa they have slowly lost that wonderful intake sound due to burying it deeper and deeper in the engine. First we had carbs. If you take off the filter and look down the throats you can see the inside of the engine. You cannot get much closer to the action than that. Fire it up and you can hear what the engine is thinking before it even happens. Each cylinder has it’s own throttle body and gets tuned for it’s individual needs.
Next came SPICA. Not much change in sound here. Perhaps there was a little less popping through the intake, but in general you have the same aural pleasures.
So now after years and years and years of listening to an engine from the front and the back, Alfa slaps on Bosch FI to bring things up to date. Is Bosch the problem here? No. I happen to like the computerized fuel injection for its reliability and general ease of maintenance. The problem here is how Alfa went about implementing things. Instead of using a set of paper-thin filter elements or an equally thin sheet metal filter housing, Alfa slapped on a massive aluminum intake plenum. Are plenums bad? No. They are great for engine breathing, the bigger the better. But does it have to be so thick? I think not. Rather than a thick-skinned aluminum casting which absorbs all the wonderful Alfa music, we could have easily gotten away with another sheet metal box. And where did all the individual throttle bodies go? Now we only have a single throttle on the far side of the plenum.
But intakes alone do not an engine note make. A great deal of the sound comes from the engine itself. The solid lifters make a nice rhythmic tapping sound. On Bosch cars you can hear the fuel injectors fire with a nice rapid click. If your engine is worn, a piston slap or something worse might make your car somewhat unique.
I think the key to engine music is the ability to hear the engine in all its glory. It just is what it is and just by chance it is a sound that touches our souls. We live in an era when engines are hidden by plastic covers. Sound dampening panels and insulation blankets deprive us of our engine notes. Long, well-built, thick walled exhausts are scientifically designed to muffle an engine without hurting performance. What is this world coming to? I don’t have the answer, but when I get especially depressed about it I go out into the garage and fire up one of my cars. A few blips of the throttle releases sounds that make my heart flutter and life feels good again.
Side note: American V8s are mostly exhaust note rather than intake. My reasoning is the long runners on the cast intake manifold muffle the intake sounds somewhat. It is then coupled to a carburetor with a single or maybe two butterflies. I will take individual runners and throttle bodies any day. I have heard that small blocks with webers are incredibly intoxicating to listen to. When I find one, I will let you know.
Second side note: Why do Ferraris and Small blocks sound so different? The answer is in the crankshaft. Ferraris use a flat plane crank meaning the throws are 180 degrees apart. This gives it a fundamental quality like two four cylinder engines back to back. The result is a beehive sound that makes the engine scream even when it is not working hard. The American designed v8 engines of yore all use a cross plane crankshaft. The throws are 90 degress apart. This causes a harmonic to form in the exhaust that cancels out every other cylinder. Now the term “lazy” or “loping” makes more sense when used to describe these engines. Even when at full tilt they sound like they are barely working. That is because we only hear half the song!
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