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Old 03-06-2020, 11:02 AM
allenga allenga is offline
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Default Exhaust Weights to Stop Interior Resonance

I am reading some are successful in eliminating interior vibration, drone by clamping weights onto the exhaust.

Have you tried this.

I have headers and Spintech 9000XLs and am getting vibrations and resonance.

I have an x pipe, nothing is hitting floor. Two layers of sound deadener on floor pans.
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Old 03-06-2020, 11:19 AM
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leeklm leeklm is offline
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No experience, but I have read that weights are typically used to target high frequency resonance, whereas we are usually dealing with low frequency on our exhaust systems

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Old 03-06-2020, 02:30 PM
76TA462 76TA462 is offline
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Not sure if this is of interest. For clearance issues (lowered car) I replaced my Dynamax Welded with Borla Pro XS Mufflers 40352. That gave way too much resonance. I added Vibrant 1793 bottle style resonators just after my headers, and problem solved.

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Old 03-06-2020, 02:41 PM
jerry455 jerry455 is offline
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Weights like that have been added to some of the later GM trucks and vans with 4.3 V-6's. They have a resonance in the exhaust and there was a weight that they came out with that they put near the tailpipe. It dampened some of the resonance.

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Old 03-13-2020, 11:21 AM
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Formulajones Formulajones is offline
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Those Spintech mufflers are horrible for that. I ran a spintech on a 4" exhaust system I had on a 4th gen for a short period, it came off for a magnaflow that was marginally better.

Swapping those mufflers would be a MAJOR improvement. Personally I'd have a set of Dynomax on there and most all of your problems will go away.

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Old 03-13-2020, 12:09 PM
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Keith Seymore Keith Seymore is offline
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OE manufacturers conduct a "modal analysis" of the design intent exhaust system to determine locations of peak amplitude (highest movement) and "node" points (dead spots).

This is done by placing accelerometers along the length of pipe, whacking it with a hammer, and monitoring the frequency response.

If you start hanging weights randomly without doing that exercise you are just shooting in the dark.

K

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Old 06-15-2020, 10:55 PM
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If the weights had a rubber separator between the weight and the bracket, they might do some good.

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