How to reduce the 3000 rpm resonance with a straight thru system?
#1
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I like the sound of the WRsport BB (Oval) but when it's on the end of a straight thru system, it gets too boomy at 3000rpm. At 2k or 4k revs it's fine with a great idle burble and howl at WOT high revs, but at 3K on the motorway it's a pain. Almost makes a car feel slower some-how.
Does anyone know of a good centre pipe that will quieten things down a bit but still be back-pressure free?
OR can someone lend me a STI centre/Magnex (with resonator) to try out pretty please?
F
Does anyone know of a good centre pipe that will quieten things down a bit but still be back-pressure free?
OR can someone lend me a STI centre/Magnex (with resonator) to try out pretty please?
F
#4
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Hi Floyd,
I have a SS Downpipe, with Magnex(Resonated)centreipe and 3.5" backbox. Took this option cos I didn't want a boomy exhaust on the Motorway......
Well I'm afraid its still boomy
. Well to me it is..
Have noticed it gets much worse on three occasions
1) Rear Windows open (obvious I know)
2) Rear seat down (again obvious I know, but it does mean there isn't much sound deadening coming from the rear except the seat itself)
3) When there are 4 people in the car, its boomier. How does the weight cause this, I don't know?????
J
I have a SS Downpipe, with Magnex(Resonated)centreipe and 3.5" backbox. Took this option cos I didn't want a boomy exhaust on the Motorway......
Well I'm afraid its still boomy
![Confused](https://www.scoobynet.com/images/smilies/confused.gif)
Have noticed it gets much worse on three occasions
1) Rear Windows open (obvious I know)
2) Rear seat down (again obvious I know, but it does mean there isn't much sound deadening coming from the rear except the seat itself)
3) When there are 4 people in the car, its boomier. How does the weight cause this, I don't know?????
J
#5
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Putting a PE Power Manifold on my car got rid of the boom altogether. You lose the burble too, which you may not like. Suited me fine. Bit of a sledgehammer to crack a walnut though :-) The extra 20-30lbft of torque came in handy too.
Steve
Steve
#6
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Stephen, you are correct that the cost of a manifold is a lot to sort this out! I wonder if porting the headers would help?
In the meantime has anyone got an STI/magnex type centre with resonator they could lend me? I'll buy it/one if it works of course! Please, please, pretty please.
I did put some sound proofing material across the boot and under the seats but it made little impact. I'm going to try a big duvet in the boot to see if it helps (light and thick - just like me).
F
In the meantime has anyone got an STI/magnex type centre with resonator they could lend me? I'll buy it/one if it works of course! Please, please, pretty please.
I did put some sound proofing material across the boot and under the seats but it made little impact. I'm going to try a big duvet in the boot to see if it helps (light and thick - just like me).
F
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