NASA-VA Jon Felton wrote:
>
> Loud in grid, Ha! How about Club Racing?
>
> Picture being anywhere near the paddock, the
> grid, or the track during an ITA race. Picture about
> 30 of those RX-7's going by at about 8000 rpm in
> 3rd gear. Ouch!
>
> The legal limit at Summit Point is 103db but those
> who are above it weld a 90 degree "turn pipe" on
> their muffler tip, to point the sound away from the
> sound meter!
You know, now that you mention it, the 90' bend does do a lot on the
obnoxious meter.
I had a DSP Bugeye with 1275 and headers that ran straight back to the
rear axle, then through a new "Cherry Bomb" muffler, and was advised by
others at the next event thaqt my car was obnoxiously loud. I had
noticed that while driving sanely through my neighborhood that it set
off car alarms :-)
So......I purchased from Checker a standard 90' bend and attached to the
end of the muffler, and all complaints went away. The car was
significantly quieter, and no slower.
I'm no sound engineer, but I'll bet it had something to do with breaking
up the straight path of the sound wave.
S Meyers
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