How bad is the RB long primary system, anyway?
08-28-11, 03:02 PM
#1
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Thread Starter
How bad is the RB long primary system, anyway?
I now have a complete RB "street port" exhaust system. I plan on installing it next week.
Does anyone have any real-world (dyno) experience with these, as compared to other setups?
My current exhaust is a Mind-Train and 2.5" all the way back, and I'm getting 4psi backpressure over 6000rpm. And the noise is getting unbearable. I'm hoping that two 2" pipes will flow more than one 2.5" pipe, and from experience with a friend's '79, the system is actually pretty quiet as rotaries go.
Note that the rear muffler is a 1-into-2 glasspack style muffler, not the chambered muffler that some people have posted a cutaway of. So it's like there's an X pipe after the axle.
Does anyone have any real-world (dyno) experience with these, as compared to other setups?
My current exhaust is a Mind-Train and 2.5" all the way back, and I'm getting 4psi backpressure over 6000rpm. And the noise is getting unbearable. I'm hoping that two 2" pipes will flow more than one 2.5" pipe, and from experience with a friend's '79, the system is actually pretty quiet as rotaries go.
Note that the rear muffler is a 1-into-2 glasspack style muffler, not the chambered muffler that some people have posted a cutaway of. So it's like there's an X pipe after the axle.
08-28-11, 03:18 PM
#2
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i guess we'll see... i really liked mine, its unloud, and compared to the short RB system the low end was WAY better, much broader powerband.
plus i think its literally bulletproof.
on the minus side there are a couple of construction flaws that we know about. the header kind of stinks at the exhaust port. the muffler pipes aren't 2" like the rest of the system, and it might collect at the wrong place for a big ported engine.
not that hard to fix if its a problem....
plus i think its literally bulletproof.
on the minus side there are a couple of construction flaws that we know about. the header kind of stinks at the exhaust port. the muffler pipes aren't 2" like the rest of the system, and it might collect at the wrong place for a big ported engine.
not that hard to fix if its a problem....
08-28-11, 04:06 PM
#3
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Thread Starter
Yeah, the header definitely sucks at the engine flange. And since it's a used header, grinding it to port-mismatch in the correct direction is a hardcore pain in the ***.
The muffler pipes looked fairly large. Maybe it's because I have a system designed for a GSL-SE?
And jeez, is it ever heavy! I might end up moving my battery to the left side of the car
The muffler pipes looked fairly large. Maybe it's because I have a system designed for a GSL-SE?
And jeez, is it ever heavy! I might end up moving my battery to the left side of the car
08-29-11, 07:28 AM
#5
Waffles - hmmm good
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I went from an old Rotary Engineering exhaust setup to a used ( but very solid ) RB
SP setup. With the RE setup I was at 134whp with the mods in my sig. Haven't
gotten a chance to dyno it since I put in the RB SP setup.
Butt dyno says its a bit better, definitely sounds better.
I'll post up and PM you when I do get dyno numbers again.
SP setup. With the RE setup I was at 134whp with the mods in my sig. Haven't
gotten a chance to dyno it since I put in the RB SP setup.
Butt dyno says its a bit better, definitely sounds better.
I'll post up and PM you when I do get dyno numbers again.
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