Borla XR1 Race. Resonance???

[E. J.]

I’m planning on buying, either Borla’s Stinger, single outlet (140017), or their XR1 race system (14778).
I’m concerned about resonance, but not about loudness.

I would like to go the XR1 route but I am afraid of the resonance on long trips.

My question is, has anyone tried tuning out the resonance through the use of clamp on weights?

Since the rear interior compartment of our cars is actually glued onto the frame, without the use of any pliable body mounts, any vibration coming through the exhaust mounts will really radiate through the rear tub like a giant speaker cone.

Loud will always be loud, but resonance is a tunable quality. The aftermarket probably doesn’t want to add the excess weight, since part of their advertising is directed at a weight reduction from stock. But clamp on weights to the pipe are easily removed at the track.

I had experience with exhaust resonance on one of my wife’s previous cars. A 4 cylinder Sunfire that developed seriously annoying resonance after a muffler and tailpipe change. After two return trips to the muffler shop they dragged me out to the car, while it was up on a lift to show me that no part of the exhaust was against the floor pan. With someone in the car they ran the engine at various RPM ranges. At certain points the pipes just shook like crazy. They solved the problem by attaching a clamp on weight which they obtained at the Pontiac dealer. They tried the weight at a few different locations along the pipe until the vibrations in the pipe were minimized. The difference inside the car was unbelievable. From under the car there was no change in the noise level when the pipe was vibrating.

I want comments, yea or nay. If you have tried it, (1) Where did you attach the weights? (2) How much weight, etc.

Thanks for your help.

Ed

 

[C5NGAGE]

Mallet B&B PRTs

My 98 had Corsa Pace muffers for 3 years. Everyone including me loved them. Last week I was rearended on teh beltway and one muffler was ripped off.
I am lookin gat the Mallet version of the B&B PRT mufflers as a replacement. They are sinlge outlet with straight flow and and a hang on Resonantor near the original Muffler location.
I expect some resonance and will want to reduce it at cruising speeds. Can you offer any other input as the weights trick, sounds logical and easy to do.
Dennis

 

[E. J.]

c5ngage

All that I can add to the original post is that the weight used on my wife's car looked like a exhaust pipe clamp with a round weight attached to its base.

I didn't handle it myself, but it couldn't have weighed more than 1 or 2 pounds.

As I recall the weight was attached near the middle of the run of the pipe between two hangers.

Ed