Another 2 into 1 question, Rinehart or Fat Cat
#11
12-19-2009, 11:47 AM
true, but, their torque curves and how they come on through the RPM range will be quite different. we ride 99% of the time through the rpm range and not at peak HP and torque. Heck, my big radius 2-2(BCT baffles) had about the same peak HP and torque on the dyno, yet the curve and the way the D&D feels on the road over the big radius is unbelievably different.
Cost and looks seem to be about equal. I doubt sound would really vary that much between them, though I have read the FatCats are ever so slightly quieter.
#12
12-19-2009, 11:47 AM
Road Warrior
#13
12-19-2009, 12:27 PM
Elite HDF Member
Very well said. Totally agree.
true, but, their torque curves and how they come on through the RPM range will be quite different. we ride 99% of the time through the rpm range and not at peak HP and torque. Heck, my big radius 2-2(BCT baffles) had about the same peak HP and torque on the dyno, yet the curve and the way the D&D feels on the road over the big radius is unbelievably different.
#14
12-19-2009, 12:39 PM
so it is simple, you want a nice torue curve get a D&D, you want less power in your usable rpm range get the rinehart's.
#15
12-19-2009, 05:02 PM
Tourer
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1. That's part of the problem, Winter here in Minnesota, no riding.
It's pretty warm out today, all the way up at 22 degrees...
2. Never said anything about Handling. Just as an example of where I'm used to revving a motor
3. Exhaust gas velocity. Yes. Exhaust theory: You have to keep the exhaust gas velocity high to make power. That's why you loose torque if you go with an exhaust that's too large. The velocity drops and each pulses exhaust gases don't effectively get out of the way of the next one. If the velocity is high you get a scavenging effect.
If you go too small the exhaust velocity stays high, but it becomes a restriction.
So Ideally you want it just large enough to flow at max throttle, so it's not a restriction there, and just small enough to keep velocity high at small throttle openings.
Couple that with large abrupt direction changes tend to slow the exhaust down.
It's part of why Header Wrap works to make more power. Without header wrap you're radiating heat out of the headers. Well that lost heat causes the exhaust gas to shrink. This causes it's velocity to drop, and so on.
Conversely when you wrap the headers the heat stays in the exhaust gases and velocity stays high.
Yes I am an engineer, why do you ask?
It's pretty warm out today, all the way up at 22 degrees...
2. Never said anything about Handling. Just as an example of where I'm used to revving a motor
3. Exhaust gas velocity. Yes. Exhaust theory: You have to keep the exhaust gas velocity high to make power. That's why you loose torque if you go with an exhaust that's too large. The velocity drops and each pulses exhaust gases don't effectively get out of the way of the next one. If the velocity is high you get a scavenging effect.
If you go too small the exhaust velocity stays high, but it becomes a restriction.
So Ideally you want it just large enough to flow at max throttle, so it's not a restriction there, and just small enough to keep velocity high at small throttle openings.
Couple that with large abrupt direction changes tend to slow the exhaust down.
It's part of why Header Wrap works to make more power. Without header wrap you're radiating heat out of the headers. Well that lost heat causes the exhaust gas to shrink. This causes it's velocity to drop, and so on.
Conversely when you wrap the headers the heat stays in the exhaust gases and velocity stays high.
Yes I am an engineer, why do you ask?
Last edited by '09fxdb; 12-19-2009 at 11:25 PM.
#16
12-19-2009, 05:08 PM
No in practical application from reading people experiences it seems like the D&D is more of a low-end pipe. Relative, as it doesn't exactly suffer on the top end.
And that the Rinehart is more of a high end pipe. RPM wise that is.
Sound like I got my facts right so far?
And that the Rinehart is more of a high end pipe. RPM wise that is.
Sound like I got my facts right so far?
The rinehart is more geared towards milder builds while the D & D kicks *** on a wide range of builds. Besides, Rinehart is a different company (as of this year) and their warranty is almost non-existant. I'd stay away from them. However, their Bub 7 2 into 1 is supposed to be a pretty good performing pipe. But there is a risk that they ain't even gonna be the same now that they ain't even gonna be made at the same place anymore. Buy them if you are okay with risk taking.
D & D's are a proven performer, with a fit and finish that is hard to beat.
#17
12-19-2009, 05:14 PM
The bub 7 is not the same pipe and will perform within range of the Fatcat.
#18
12-20-2009, 09:35 AM
interesting about the rinehart. I had actually remember a few threads a year+ ago about a few people loosing power with the rineharts. I haven't found them in my search though.
#19
12-20-2009, 10:12 AM
Road Warrior
#20
12-20-2009, 12:13 PM