Cat Bypass easy to do?
08-30-2006, 01:37 PM
#16
I realize the function of the springs are supposed to control it, but in addition w/pressure........? No?
1) Gas flowing from the head to atmosphere
2) A series of rarefactions and compressions (an acoustic wave)
The gas flow speeds up and slows down depending on what constraints are imposed by PVT and pipe characteristics, which include dimensions but also include transitions, shape and internal structure.
The acoustic wave varies in frequency and length. These means that as the revs rise there is a constantly varying acoustic signature at the ports, when this is a rarefaction it helps remove spent combustion byproducts from the engine(this is a good thing) when it is a compression it impedes the flow(this is a bad thing). No matter what the exhaust there will always be some points in the rev range where good things are happening and some points where bad things are happening. The exhaust designer just makes an attempt to have the good things happening at the right time. In general the better the exhaust is at one particular point the worse it will be at other points, so an attempt is made to balance out the system maximizing the gains while minimizing the losses.
08-30-2006, 01:38 PM
#17
Originally Posted by TRINITONY
How does a Harley compare to cat bypass with RSR? My car sounds so so quiet when driving next to a Harley.. 
And lately that's been quiet often.
And lately that's been quiet often.
08-30-2006, 04:21 PM
#18
Burning Brakes
I have cat bypass pipes. They are loud. I like it. But I primarily do it to help reduce underhood engine temperatures with a hope of benefiting engine life.
08-30-2006, 04:28 PM
#19
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Have a can of some rust eater penetrating spray available and/or buy new bolts and nuts for the clamps and just break the bolts off or cut them off. I bought extra bolts and nuts.
08-30-2006, 05:27 PM
#20
Drifting
Thread Starter
Hey thanks for all the great input. I will just do the mufflers for a start and see what happens from there.
Resonance is something I will try to avoid.
On my 3.6 Turbo there was very little resonance with Fabspeed cat bypass and muffler, but the sound was great. Ovbiously a bit different with a NA car.
Resonance is something I will try to avoid.
On my 3.6 Turbo there was very little resonance with Fabspeed cat bypass and muffler, but the sound was great. Ovbiously a bit different with a NA car.
08-30-2006, 08:06 PM
#21
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OK; Really dumb question here. I really don't know much about the exhaust system, other than knowing that it's a topic on par with airbox, induction, K&N, undertray, etc.
When one says "cat bypass", are they talking about removing the catalytic converter(s) and installing a straight pipe? And are we talking performance improvements or more dB's?
When one says "cat bypass", are they talking about removing the catalytic converter(s) and installing a straight pipe? And are we talking performance improvements or more dB's?
08-30-2006, 11:14 PM
#22
Race Car
Originally Posted by farmerjohn
When one says "cat bypass", are they talking about removing the catalytic converter(s) and installing a straight pipe? And are we talking performance improvements or more dB's?
08-31-2006, 03:45 PM
#24
Drifting
Thread Starter
"according to Fabspeed, you don't actually get any extra HP. Real benefits are less weight and less heat - the sound is just a bonus"
I know they don't, but why do they say these make 14 HP then?
I thought claims like that in America were illegal if they are not correct.
Doesn't bother me at all though, I'm still buying some mufflers.
I know they don't, but why do they say these make 14 HP then?
I thought claims like that in America were illegal if they are not correct.
Doesn't bother me at all though, I'm still buying some mufflers.
