1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

rotarys are loud?

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Old Feb 11, 2008 | 09:10 PM
  #1  
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From: Port Orchard WA
rotarys are loud?

No ****, but why. Why are they louder than any other uncorked engine? My buddies derby car with stacks isnt as loud.
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Old Feb 11, 2008 | 09:25 PM
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RX7 allnight's Avatar
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they need more air volume? and the exhuast has a shorter travel from the block? correct me if anyone of these are wrong.
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Old Feb 11, 2008 | 09:27 PM
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No valves or heads to get in the way of the noise, and fast opening/closing of the ports as compared to valves.
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Old Feb 11, 2008 | 10:12 PM
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Easier to wake up the neighbors.
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Old Feb 11, 2008 | 10:28 PM
  #5  
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Is it realy just the lack of valves, fast opening port, and no exhaust runner? That just seems a little over-simplified.
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Old Feb 11, 2008 | 10:28 PM
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Yes, if I may induldge. About 7 or so years ago, when I was a young highschool chap. I had a 83 gsl with header/straightpipe/stock muffler (got USED for 50 or 100 bones). Anywho, I'm with a friend and a nissan or some kind of car pulls up next to us while were going about 20mph. I of course push in the clutch, rev the car crazily and then drop the clutch while in 2nd gear... bzrzzrzzrrrBLAAAAAAcCKCK
BORAKk... you get the point, running headers only about 1/2 a second after I drop the clutch... It put a look of fear on the 2 guys in the car next to me, and the 2 guys in my car . Drove to a fellow rotor heads appt, wasn't there, but a guy with a drag camaro gave me 2 thumbs up LOL ... Ohh the days of putting crap on crappily.
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Old Feb 11, 2008 | 10:35 PM
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technically speaking our engines are over simplified so it only makes sense that the answer seems over simplified (refering to number of moving parts etc.)
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Old Feb 11, 2008 | 10:42 PM
  #8  
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over simplified until you try to figure out timing and port opening/closure. Yes a triangle rotationg in a peanut is over simplified now try to explain that your car has 4 spark plugs and only three moving parts and see the looks you get from that person. One thing ive learned from my car is nothing is as simple as it seams.
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Old Feb 11, 2008 | 10:45 PM
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I never said it was simple, i said it was simple in terms of moving parts lol. Its the most simple and (one of) the most complex engines out there
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Old Feb 12, 2008 | 12:28 AM
  #10  
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Because of the smooth,rotating nature of the combustion chamber,the power cycle is still occuring when the ports are uncovered and the exhaust phase begins.Its like the barrel of the gun,the explosion starts a closed up space,but it continues as the pressure exits the confined area.And of course,sometimes the apex seals play the role of the bullet!

There is also the sharpness of the tone,which is due to the quick opening and closing of the ports.Piston engines let thier valves down into the seats very slowly and carefully to prevent them from pounding into the head,thats why the cam lobes are smoothly ramped from the base circle,up to the lobe tip.And the camshaft is only turning 1/2 the crank speed,making valve control even easier.
Rotaries and 2 stroke piston engines have their ports opend and closed by a sliding piston that is moving very quickly,directly over the port surface. Ever turned a rotary over by hand on an engine stand? Even at that super slow cranking speed,the ports open and close with a solid "FWUP" of suction and pressure.
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Old Feb 12, 2008 | 04:24 AM
  #11  
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Rotaries can be seen as being very simple, since there are only 3 moving parts but there are 100+ seals that are required to make up one engine. So simply yet complex.
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Old Feb 12, 2008 | 10:41 AM
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^concurred
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Old Feb 12, 2008 | 03:38 PM
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[QUOTE=redbstd;7856035] 4 spark plugs and only three moving parts QUOTE]

Now thats a good saying! What has 4 spark plugs and only 3 moving parts? Ask someone that and see if they get it right, if they don't know your a rotor head already.
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Old Feb 12, 2008 | 04:27 PM
  #14  
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Smaller engine, smaller car, more revs, unique sound. It's closer to an aviation and motorcycle engine than a traditional piston engine IMO.
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Old Feb 12, 2008 | 05:17 PM
  #15  
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Wankle **** **** ****!
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