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WARP TEN · 03-10-2014

Those who mention a "Drone" if you open up the closed section of the mufflers are correct. Our engines produce frequency spikes that produce noticeable and annoying resonance at two primary RPM points--1,800 and 3,400, with a less noticeable one around 2,400. The closed pipes of the earlier mufflers are closed for a reason: They are behind the Helmholtz resonators which mitigate the resonance at (I think) the 1,800 RPM point, while the center resonator handles the 3,400 point. (Or vice versa; can't quite recall). Each resonator is a closed chamber with one opening and is sized for a specific frequency. The Corsa system uses a similar feature they call quarter wave tuners, as do some others. So opening up the Helmholtz resonator would result in an unpleasant exhaust sound. Later stock mufflers have only one outlet but still retain the resonator section to combat resonance.--Bob

03-10-2014	#8
WARP TEN Join Date: Apr 2007 Location: Lake Bluff, IL Posts: 2,147	Re: Mod To Stock Mufflers Those who mention a "Drone" if you open up the closed section of the mufflers are correct. Our engines produce frequency spikes that produce noticeable and annoying resonance at two primary RPM points--1,800 and 3,400, with a less noticeable one around 2,400. The closed pipes of the earlier mufflers are closed for a reason: They are behind the Helmholtz resonators which mitigate the resonance at (I think) the 1,800 RPM point, while the center resonator handles the 3,400 point. (Or vice versa; can't quite recall). Each resonator is a closed chamber with one opening and is sized for a specific frequency. The Corsa system uses a similar feature they call quarter wave tuners, as do some others. So opening up the Helmholtz resonator would result in an unpleasant exhaust sound. Later stock mufflers have only one outlet but still retain the resonator section to combat resonance.--Bob __________________ 2016 Long Beach Red Z06 #10281 "POPS Z" 1995 Polo Green #409 "WARP TEN"--Haibeck 350/510 package, 4.10s, Hurst, Stock Exhaust with QTP Cutouts --Sold but still running strong 1993 Quasar Blue #161 "HIL KING" --Sold but still running strong, now with more than 120,000 miles 1967 Marlboro Maroon/Saddle Corvette Coupe 300 hp/4-spd --Sold a long time ago ZR-1 Net Registry Founding Member #95 NCM Lifetime Member Favorite Quote--Attributed to Mickey Thompson: "Too Much Horsepower is Almost Enough"