787b (4 Rotor) Sound From Single Turbo REW - Is It Possible?
I'll give you a serious answer, it probably is impossible to get that sound with a 13B, the thought that came to my mind is to use multiple sport bike exhaust to be equivalent to a 3 or 4 inch circumference, not sure if it will achieve that high pitch sound as I never got the chance to do it.
If I was still in Cali I probably would have done it already since there are a lot of muffler shops there that can fabricate it.
If I was still in Cali I probably would have done it already since there are a lot of muffler shops there that can fabricate it.
Part of the reason 3- and 4-rotor engines sound so unique is they have more combustion events at the same engine RPM. It's not a matter of sound level or muffling, it's like playing a drum roll with two hands instead of one (or two drummers playing with two hands if that's easier to imagine)... the result is more powerful but more importantly the tone sounds more "smooth" or "even" and also high-pitched.
Part of the reason 3- and 4-rotor engines sound so unique is they have more combustion events at the same engine RPM. It's not a matter of sound level or muffling, it's like playing a drum roll with two hands instead of one (or two drummers playing with two hands if that's easier to imagine)... the result is more powerful but more importantly the tone sounds more "smooth" or "even" and also high-pitched.
Joined: Mar 2004
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From: King George, VA USA
Part of the reason 3- and 4-rotor engines sound so unique is they have more combustion events at the same engine RPM. It's not a matter of sound level or muffling, it's like playing a drum roll with two hands instead of one (or two drummers playing with two hands if that's easier to imagine)... the result is more powerful but more importantly the tone sounds more "smooth" or "even" and also high-pitched.
:]
you will also have to pair exhaust pulses 180* apart from each other to cancel out specific frequencies......this is why bikes/ferrari's/F1 cars have a high pitch sound......they have crankshafts that pair exhaust pulses 180 degrees apart.....this would be the difficult part with a 2 rotor considering there are only 2 exhaust ports....lol.....
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Joined: Jan 2006
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From: Seattle
I hadnt realized what I was esentially asking was 'Why doesnt my 4cyl sound like an 8 or 12 cyl?' - Because it just isn't
I.i.r.c. eccentric shaft throws are 180, though each stroke is not.
Thanks for elaborating on this, I also hadnt realized how much other factors play a part
I.i.r.c. eccentric shaft throws are 180, though each stroke is not.
Thanks for elaborating on this, I also hadnt realized how much other factors play a part
Joined: Mar 2001
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From: https://www2.mazda.com/en/100th/
everyone is really close. the 2 rotor rotary has a combustion event every 180 degrees of crank rotation, just like a 4 cylinder.
the 3 rotor is every 120 degrees, like a 6 cylinder.
the 4 rotor is every 90 like a v8, but not a typical american v8, the even firing 90 degree events are exactly like a FLAT PLANE crank v8, like what Ferrari has used for decades.
and yes the 787B does sound like its ripping the fabric of time... that's a great way to put it.
and yes the 787B has a big muffler, out of all the vintage racing hardware mazda brings out the 787B sings a great song, but its also one of the quieter ones. the loud one is the car and driver rx2 with the original exhaust, its the loudest noise i've ever heard.
the 3 rotor is every 120 degrees, like a 6 cylinder.
the 4 rotor is every 90 like a v8, but not a typical american v8, the even firing 90 degree events are exactly like a FLAT PLANE crank v8, like what Ferrari has used for decades.
and yes the 787B does sound like its ripping the fabric of time... that's a great way to put it.
and yes the 787B has a big muffler, out of all the vintage racing hardware mazda brings out the 787B sings a great song, but its also one of the quieter ones. the loud one is the car and driver rx2 with the original exhaust, its the loudest noise i've ever heard.
Agree with the statements above about the uniqueness of the sound, there is no substitution. That being said I've heard 3 rotors come close when they have a bridge/Periph port and are balanced to 10,000+ RPMs.
Here's a 3 Rotor PP at 11K:
http://www.youtube.com/watch?v=JcyvTuoslAA
~CYD
Here's a 3 Rotor PP at 11K:
http://www.youtube.com/watch?v=JcyvTuoslAA
~CYD
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