Removing crossover....tone change?

05Commemorative

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For me, I kept the factory mufflers and crossover, but replaced factory cats w/hi-flow cats. Heat problem in footwells gone, much better idle sound, but not super loud at full song and zero drone at any rpm.

So:

if wanting to reduce heat and mild increase in sound, replace factory cats
reduce weight, remove crossover and cats
 

Sonoman

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People always ask why these Vipers sound so different from a V8. Using a 90-degree V-spacing between the two banks of cylinders, with only eight cylinders you can fire every 90 degrees and complete the firing order every two revolutions (360 x2=720 degrees; the four-stroke engine crankshaft rotates twice to accomplish the intake, compression, power and exhaust strokes). So you get a nice, even-fire sound with the exact same timing between each firing of a cylinder on a 90-degree V-8. (This assumes it has a cross-plane crankshaft where each bank of four cylinders has 90 degree offset between each subsequent connecting rod).

The 90-degree V-10 used in the Viper does not fire at evenly spaced intervals, which creates all kinds of interesting acoustic effects whether or not you combine the exhausts of the two banks together. Instead of the cylinders firing 90-90-90-90... as in a typical V-8, we get firing intervals of 90-54-90-54-90-54-90-54-90-54... The ear detects this odd cadence and the harmonics associated with it.

While it may sound like a delivery truck from idle to 2500 or so RPM, I love the sound of the Viper at higher revs.

BTW, Lamborghini uses two different V-10s, the older 5.0 liter has a flat-plane/even firing crank while the post-2008 5.2 liter is an odd-fire just like the Viper (90-54-90-54...).

Man, I gotta quit drinking beer while reading the forum-- was thinking about 72-degree V-10s and 90 degree V-8s and kept typing intervals for a 72 degree motor on the V-8 examples. Apologies for the confusion, but the point on sound was still valid... and it's too late to edit the original post so I changed the numbers in the quoted text above.

Reminds me of the old joke among mathematics professors "Alcohol and Calculus don't mix-- never drink and derive".
 

345s-bspinnin

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I vote to keep the cross-over. I know I am the minority, but I have nothing but respect for the folks who designed the Gen III OEM setup.

My setup consists of a heads/cam Gen III, 1 3/4" American Racing Headers, 3" cat-less exhaust system (test pipe), and onto OEM exhaust with crossover. At idle, hearing the 10-cyl mill's lumpy idle on both sides exudes a sound that demands respect. Slicing the system into 2-5-cyl engines creates a choppy idle which sounds amiss. At hwy speeds, its is as quiet as when completely stock. Zero noise and no drone. Perfect for the long cruises or when taking the Ms. out to the city centre. However, when the fat pedal hits the floor, that exhaust system screams deep, loud, and progressively smoother as the RPM climbs into the red. Its quite an intoxicating sound as your approach redline.

The OEM system with crossover provides phenomenal sound at idle, zero noise in the hwy while cruising, and a very exotic and authoritative sound at WOT. The aforementioned defines a perfect exhaust system in my book. My $.02
 

Ripper

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I completely dig this idea for my ride in the future !

Hope all is going well bud !



I vote to keep the cross-over. I know I am the minority, but I have nothing but respect for the folks who designed the Gen III OEM setup.

My setup consists of a heads/cam Gen III, 1 3/4" American Racing Headers, 3" cat-less exhaust system (test pipe), and onto OEM exhaust with crossover. At idle, hearing the 10-cyl mill's lumpy idle on both sides exudes a sound that demands respect. Slicing the system into 2-5-cyl engines creates a choppy idle which sounds amiss. At hwy speeds, its is as quiet as when completely stock. Zero noise and no drone. Perfect for the long cruises or when taking the Ms. out to the city centre. However, when the fat pedal hits the floor, that exhaust system screams deep, loud, and progressively smoother as the RPM climbs into the red. Its quite an intoxicating sound as your approach redline.

The OEM system with crossover provides phenomenal sound at idle, zero noise in the hwy while cruising, and a very exotic and authoritative sound at WOT. The aforementioned defines a perfect exhaust system in my book. My $.02
 

viperbilliam

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I vote to keep the cross-over. I know I am the minority, but I have nothing but respect for the folks who designed the Gen III OEM setup.

My setup consists of a heads/cam Gen III, 1 3/4" American Racing Headers, 3" cat-less exhaust system (test pipe), and onto OEM exhaust with crossover. At idle, hearing the 10-cyl mill's lumpy idle on both sides exudes a sound that demands respect. Slicing the system into 2-5-cyl engines creates a choppy idle which sounds amiss. At hwy speeds, its is as quiet as when completely stock. Zero noise and no drone. Perfect for the long cruises or when taking the Ms. out to the city centre. However, when the fat pedal hits the floor, that exhaust system screams deep, loud, and progressively smoother as the RPM climbs into the red. Its quite an intoxicating sound as your approach redline.

The OEM system with crossover provides phenomenal sound at idle, zero noise in the hwy while cruising, and a very exotic and authoritative sound at WOT. The aforementioned defines a perfect exhaust system in my book. My $.02

I found this to be true also but the cabin heat was still a problem despite hi-flo cats. When I took the crossovers out, the drone and loudness went up significantly but the cabin heat (even in footwell area) went down significantly. I dumped the headers/cats and went back to factory but still left out the crossovers. Loudness and drone is tolerable as well as cabin heat. Additional popping and spitting is still there that the crossovers took care of. Still looking for improvement. The only thing I can think of is a Corsa system with the header/hi-flo cat setup that would possibly accomplish all the mods we desire without most of the drawbacks. I don't care for the raspiness of Corsas.
 

VicTxV10

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I think the Gen4 has a different tone because there is no crossover pipe like the Gen3. The crossover has a connection similar to an H or X pipe that allows the tone of all 10 to push out both sides. So either side of the car that you stand at you hear all 10 cylinders firing together. On the Gen4, all you hear is 5 cylinders from one side.

Wrong! There is no H or X pipe on gen3. The left side crosses over and exits on the right, and the right crosses over and exits left. You still only hear five cylinders on either side.
 

latamud

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Wrong! There is no H or X pipe on gen3. The left side crosses over and exits on the right, and the right crosses over and exits left. You still only hear five cylinders on either side.

What is that? an I pipe?

You must be registered for see images attach
 
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VicTxV10

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Wrong! There is no H or X pipe on gen3. The left side crosses over and exits on the right, and the right crosses over and exits left. You still only hear five cylinders on either side.

What is that? an I pipe?

You must be registered for see images attach

To my knowledge, that is just a bracket to hold the pipes together. I have an old one in my shop. I'll put it on the drill press and punch a hole in it and verify.
 

345s-bspinnin

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What is that? an I pipe?

You must be registered for see images attach

That is called an "H" pipe. It helps balance pressure between both banks, regardless if the flows are going in opposite directions. Very common in corvettes, Fox Bodies and F-bodies. Some folks prefer an "X" pipe to an "H", but an X can't be done since the exhaust flows are in opposite directions. Either way, our Gen III crossover H pipe serves the exact same purpose. Needless to say, it does so very successfully in the pressure pulsing departing as witnessed by its elimination of drone.

Here is an example of the C5 exhaust H-pipe:

You must be registered for see images
 
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latamud

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That is called an "H" pipe. It helps balance pressure between both banks, regardless if the flows are going in opposite directions. Very common in corvettes, Fox Bodies and F-bodies. Some folks prefer an "X" pipe to an "H", but an X can't be done since the exhaust flows are in opposite directions. Either way, our Gen III crossover H pipe serves the exact same purpose. Needless to say, it does so very successfully in the pressure pulsing departing as witnessed by its elimination of drone.

Here is an example of the C5 exhaust H-pipe:

You must be registered for see images

I think you missed my sarcasm.
 

latamud

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That is called an "H" pipe. It helps balance pressure between both banks, regardless if the flows are going in opposite directions. Very common in corvettes, Fox Bodies and F-bodies. Some folks prefer an "X" pipe to an "H", but an X can't be done since the exhaust flows are in opposite directions. Either way, our Gen III crossover H pipe serves the exact same purpose. Needless to say, it does so very successfully in the pressure pulsing departing as witnessed by its elimination of drone.

Here is an example of the C5 exhaust H-pipe:

You must be registered for see images

I think you missed my sarcasm.
 

VicTxV10

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Ok, learn something new everyday. I drilled a half inch hole in the center of the "H" and there is a cut out on both pipes enclosed by the "H" piece.
 

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