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Discussion Starter #1
My car has been getting some unwanted attention from local cops. I want to know how I could keep the noise down. I have the RPS turbo kit. Would changing the exhaust manifold/ headers to HKS or SP unit help? I heard the HKS and SP a lot more quiet than the RPS. I also have a loud and rough idle from using 272 cams. It sounds awesome but shakes the cars around it. Would steppin down to the 264s provide some noticeable improvement? FOr exhaust I have the PE but thinking of either going back to the stock with a custom 3in piping or the greddy SP. Anything I could do to the downpipe like wrap some sound deafenin stuff over it. Tips anyone?
 
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Discussion Starter #3 (Edited)
The biggest increase in noise on my system has been replacing the midpipe with a straight catless pipe... Do you still have the catalytic converter? The exhaust behind the cat didn't make much difference in overall decibel level, just changed the tone. I have the Toyomoto cast iron manifold and downpipe (extremely quiet), so I can't comment on the SP or HKS style tubular headers.
Toyomoto wraps the downpipe, but doesn't wrap the midpipe. I would assume some thermal wrap could reduce sound level. On the Lexus system, there aren't much in terms of HP gains after the cat, so I left the stock dual mufflers in the system. You can probably get the thermal wrap at Summit.
 
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Discussion Starter #4
how can any exhaust be quiter than Greddy PE? I have PE and its quite as stock exhaut.....
 

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i think what hes getting at is that the rsp waste gate dumps i belive to the atmospher unlike the sp kit hence the more noise you might need to have some one construct a wastegate set up that re-routs back in!
 
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Discussion Starter #7
I have a Greddy SP and love how quiet it is. Just purrs. Don't let anyone tell you it limits horsepower, it doesn't. Got that straight from SP.

Don't bother with changing headers, just put a quiet exhaust on.
 

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AnArKey said:
I have a Greddy SP and love how quiet it is. Just purrs. Don't let anyone tell you it limits horsepower, it doesn't. Got that straight from SP.

Don't bother with changing headers, just put a quiet exhaust on.
I also love my SP, especially because of it's great ground clearance. Unfortunately most SPs seem to rust out after a while.. When mine dies, I guess I go with the Tanabe Hyper Medallion (the replacement for the G-power).
 

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RanGer498 said:
i think what hes getting at is that the rsp waste gate dumps i belive to the atmospher unlike the sp kit hence the more noise you might need to have some one construct a wastegate set up that re-routs back in!
RPS turbo kits route the wastegate output back into the downpipe like all the other mainstream kits.

Sad, really... nothing sounds meaner than wastegate vented to atmosphere, IMHO....

Andi
 

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oh well guess he need to sell ear plugs to the cops ;) andi thanks for the info !
Andi said:


RPS turbo kits route the wastegate output back into the downpipe like all the other mainstream kits.

Sad, really... nothing sounds meaner than wastegate vented to atmosphere, IMHO....

Andi
 

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supraman
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Is there a sound decibel limit for vehicles using approved aftermarket exhausts? The pleasure is also hearing your ride dont you think!! Makes your ride a lot meaner!!

 

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the thing that pisses me off is that whenever i drive my car around its not overly loud but i have gotten pulled over and warned several times about it. but when a harley or some kinda muscle car rips by rattling the windows off the cops dont look twice:rolleyes:
 

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WHAT!!! THEY GOT SOMETHING AGAINST SUPRA OWNERS??? SMOKE EM!! :uzi:
 
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Discussion Starter #14
Andi said:


RPS turbo kits route the wastegate output back into the downpipe like all the other mainstream kits.

Sad, really... nothing sounds meaner than wastegate vented to atmosphere, IMHO....

Andi
Andi,

remind me which kits vent the wastegate to atm: Greddy?
 
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Discussion Starter #16 (Edited)
Thanks for the help guys

Yes my wastegate reroutes back to the downpipe. I will be getting an external WG soon. I want it to sound mean when I'm flooring it. What I'm trying to say is I want the car to be quiet when I dont floor it and when I'm cruising around town where theres cops all over the place.

I do have a catless downpipe and midpipe. If switching to the G-power or greddy SP doesnot help with the noise level I'll have to go with a high flow. But thats gonna be my last option.

About the G-power and SP. Does the G-power rust too? I thought both were made out of stainless steel. Whichi has better quality?

Anarkey
Have you run your car both with the cat and without? I wonder how more quiet its gonna be.
 

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Listen to Andi he is 100% correct on his above statements.

Andi,

Thanks for saving me the time typing all of those answers. :)

Later, Steve
 
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Discussion Starter #19
Yang said:
Have you run your car both with the cat and without? I wonder how more quiet its gonna be.
Yes I have. It gets quieter, but even without any cats the Greddy SP is very quiet. At cruise and idle you have to strain to hear the engine from inside the car. Trust me, the Greddy SP is VERY quiet. I had a Tanabe Racing Medallion and it's a night and day difference.
 
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