Racing Beat Collector/ streetable header

[Rotary#10]

IM picking up a Racing Beat Collector / Header from a friend for a reasonable price. I know this will make the car louder and make some power.
My current setup is okay. Which is
Stock manifold, mid-pipe (Precat delete), main cat, striaght piping to a presilencer then to a single exit 3.0 inch muffler ( both invidia). Which is loud but not too loud. I havent got any fix-it tickets yet, but I would like to keep it that way. I've also had police follow me for a bit but I keep the RPMs down. So with this collector/ header.
I planned on maybe going this route
RB collector, # (Magnaflow or Borla presilencer), Main cat,# (Another Borla or Mangaflow presilencer) then piping to a Invidia presilencer to a invidia muffler with a 3 inch tip. I don't want to be droning on the freeway or make too much excessive noise.
I still want to be able to drive this car daily.
Any suggestions fellow rotorheads ? advice on presilencers ?

[Phoenix7]

ditch the catback, keep the rest get a GOOD set of mufflers. I can't recommend anything since All I've had has been the HKS old-school catback, the one you have NOW and the RB catback. A few of the guys here can recommend something they use though.

I hear these magnaflows reduce decibel levels too:
http://www.magnaflow.com/02product/02race.asp

DUnno how much though.

[project86]

i used the RB presilencer.. but i also had an Apexi N1 muffler... not quiet haha. the HKS Hipower sounds really nice and is not loud at cruise.

Ive heard magnaflow burn up on rotarys pretty fast.. not sure how accurate that is.

[NoDOHC]

I have Dynaflow straight-through mufflers for a piston engine on mine and they have lasted for many years (I think 5 or 6). They are welded to the factory y-pipe.

With factory porting, racing beat headers and no presilencer, they were not bad at all. With modified exhaust ports, they were a bit loud, so I added a Racing Beat presilencer. (Now the car is acceptably quiet under 3,000 RPM - It still sounds like a weedwacker on crack above that though).

I have complete racing beat exhaust on my '91 and it is normal car quiet (you don't hear the engine unless you stand on it, then you mostly hear the fan).

[vex]

I have a racing beat universal resonator to a dual magnaflow perforated stainless steel tube muffler (my entire exhaust except the turbo manifold is stainless). If you choose to go this route I would make the following suggestions: Instead of a y-pipe get a single inlet with dual outlet in the diameters you want. This will restrict a little bit of gas flow but it will be a huge reduction in noise. The baffles of the 'y-pipe' portion of the muffler will help cause destructive interference on the sound, mellowing the noise level. If you choose to forgo this suggestion you will need to find the 'sweet' spot on the rev range.

I have been pulled over exactly 1 time in my car for my exhaust, ever since then I have found the sweet spot to be around 2500rpm at partial throttle (it causes nearly 100% destructive interference on the exhaust noise--means it's almost silent. I'm being literal here).

If you still want less noise you can get a 'butt plug' which is a helical tube that causes the noise and gases to swirl around the tube as well as go through it. You can even further reduce the noise by filling the helical portion of the 'butt plug' with stainless steel wool. This will cause a greater reduction in the gas flow, but a significant reduction in noise.

[RETed]

If you're looking to maximize performance (i.e. flow) and minimize noise, go with anything that is a perforated core center tube with an offset inlet versus outlet.
This will give you the best of both worlds.
Walker Dynomax UltraFLO, Magnaflow, and Borla all makes mufflers like these.
Many are stainless steel which can handle the high heat of a rotary's exhaust.
Try and find mufflers that use "stainless steel wool" as packing, as this greatly extends life over fiberglass packing.
As a rule, bigger the muffler, the better the noise suppression.


-Ted

[jerd_hambone]

I had a RB true dual header to a Magnaflow dual in/out muffler, then out to two Cherry Bombs.

It wasn't too loud, but it was loud. Sounded pretty good really.