On Thu, 20 Jul 2017 09:02:15 -0600,
rbowman wrote:

Hence, larger fitments have, essentially, no performance advantage and most
likely have a negative effect on performance overall in most cases.

But they look kewl...

Yup. We agree.

Putting an M3 badge on an otherwise 3-series bimmer makes it look faster
too!

And, whitewall tires look kewl to some, where nobody thinks that there's an
inherent performance benefit (I hope!).

There is a similar phenomenon with motorcycles.
The first thing many Harley owners do is replace the stock exhaust with
aftermarket pipes. While they've gotten better at hiding it, the OEM
exhaust has a cross over between the two pipes that people find
unappealing. ]

Interesting.
The whole point of exhaust pipes on a motorcycle are, I would assume
+ Get the hot gas out the bike without burning the rider (or the bike)
+ Get it out fast without hindering the engine HP to push it out
+ Keep the sound to a "sane" level (as determined by all within earshot)
+ Look ok to the buyer of the bike (e.g., shiny things look good to fish)

My problem with bike "sounds" is that the potato-potato-potato sound isn't
so much an issue with me as is the presumably child-like psychology of
someone whose pipes are unreasonably loud.

Why?
Do they need attention *that* badly and can't get it any way else?

Please note that I am not a psychologist so take my quick psychoanalysis of
the loud-pipe crowd with a grain of salt and some humor.

The new pipes may have less restriction and be louder. They
may be shinier. In most cases they also result in a slight reduction in
power. Most of the people aren't doing baseline dyno runs and retesting
after modifications. They are buying bling and working on the intuition
that more noise == less back pressure == more power.

Understood completely.
It's sad, but loud pipes exist, so, there must be a *lot* of people working
on those same (probably scientifically flawed) assumptions.

In a very real way, the loud pipes = more power argument stands on the same
fundamentals that the bigger wheels = more performance argument.

Sure, you can get it - but you'd be hard pressed to beat the manufacturer
in most cases, and even if you did - there are almost always engineering
(aka scientific) cons for every pro.

For example, why not just get rid of the pipes altogether?
Then you'd have the least resistance (although no tuning) of the air
outflow from the engine.

I guess the argument is that would be too loud (but some pipes I hear
riding past my house, which is on a busy street, seem *that* loud!).