Old School and Other Rotary Old School and Other Rotary Powered Vehicles including performance modifications and technical support

Muffling a P-Port

Thread Tools
 
Search this Thread
 
Old 07-02-08, 05:52 PM
  #1  
OLDROTA

Thread Starter
 
Jaime Enriquez's Avatar
 
Join Date: Apr 2003
Location: Los Angeles
Posts: 1,389
Likes: 0
Received 1 Like on 1 Post
Muffling a P-Port

I've been doing tons of research to get a reasonable noise level out of a street-driven P-Port (yes I know, reasonable is a stretch). I was looking at these universals from Racing Beat. Supposedly the same construction as the old style from the streetport setup, just larger for turbo.

I will attempt to fit 2 of these (one version is longer and the other is shorter) pre/at the rear axle.


On a local PP around here once, he ran 1 2.5" round standard rb presilencer and one side of an RB turbo II exhaust. It was nearly as quiet as my SP.

The Larger on the right is the uni-rear muff. I may have to replace the Rotaflo in the rear if I get hassled too much...
Attached Thumbnails Muffling a P-Port-16434.jpg   Muffling a P-Port-16030.jpg  

Last edited by Jaime Enriquez; 07-02-08 at 05:58 PM.
Old 07-02-08, 05:58 PM
  #2  
RX for fun

iTrader: (13)
 
Siraniko's Avatar
 
Join Date: Aug 2001
Location: Socal
Posts: 15,926
Likes: 0
Received 22 Likes on 19 Posts
brother Jaime
If you wanna hear it perform, Im using the RB universal 2.5" in my 73 RX-3 with streetport while the quattro with a TII bridge has a 3". if you wanna check it out, come-by sometime next week. Im waiting for new OC lines for the quattro so i wont be able to start it. And if you're lucky, I may take give you a ride on the 3-rotor.
Old 07-02-08, 06:02 PM
  #3  
OLDROTA

Thread Starter
 
Jaime Enriquez's Avatar
 
Join Date: Apr 2003
Location: Los Angeles
Posts: 1,389
Likes: 0
Received 1 Like on 1 Post
Gotta love summer vacation! I'll hit you up!
Old 07-02-08, 07:49 PM
  #4  
Old Fart Young at Heart

iTrader: (6)
 
trochoid's Avatar
 
Join Date: Apr 2004
Location: St Joe MO
Posts: 15,145
Likes: 0
Received 7 Likes on 7 Posts
Have you thought about running 2-1/2" dual pre-silencers off the header, then merging into a 3-4" over the axle pipe. Then you could go with a 3-4" Rotaflow or Borla. I'd use Borlas for the pre-silencers
Old 07-02-08, 08:00 PM
  #5  
RX for fun

iTrader: (13)
 
Siraniko's Avatar
 
Join Date: Aug 2001
Location: Socal
Posts: 15,926
Likes: 0
Received 22 Likes on 19 Posts
IIRC, blake (may he rest in peace) had a p-port with dual 2" to make it quiet?

I was gonna do a p-port also but I junked that idea as performance will suffer with small pipes. why build one if you cant drive it like you stole it.
Old 07-02-08, 08:17 PM
  #6  
Eats, Sleeps, Dreams Rotary

iTrader: (1)
 
ultimatejay's Avatar
 
Join Date: Nov 2006
Location: California
Posts: 4,148
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by Jaime Enriquez
I've been doing tons of research to get a reasonable noise level out of a street-driven P-Port (yes I know, reasonable is a stretch). I was looking at these universals from Racing Beat. Supposedly the same construction as the old style from the streetport setup, just larger for turbo.

I will attempt to fit 2 of these (one version is longer and the other is shorter) pre/at the rear axle.


On a local PP around here once, he ran 1 2.5" round standard rb presilencer and one side of an RB turbo II exhaust. It was nearly as quiet as my SP.

The Larger on the right is the uni-rear muff. I may have to replace the Rotaflo in the rear if I get hassled too much...
Jaime, running the 3" pre silencer and then the 3" uni high flow muffler you have pictured is about the best compromise for power and sound. It will still be loud as hell but not as loud as my system without pre silencer. If you go any other route to make it quieter you are going to lose more horsepower than the pport is worth doing. IOW- you'll have a quiet pport with the power of a streetport, so why bother.
Old 07-02-08, 08:29 PM
  #7  
Lives on the Forum

iTrader: (5)
 
84stock's Avatar
 
Join Date: Apr 2003
Location: calgary
Posts: 5,537
Likes: 0
Received 9 Likes on 5 Posts
I have a friend with a pp 13b second gen. I believe he uses Borla with the removable silencer. He says that having the silencer in kills about 20+ hp off the top end. Without the silencer it is loud as hell. My suggestion, follow what I have done. I run 2 presilencers and a magnaflow, very drivable. When I race I click the switch for an electric dump off the header (qtec). So i get the best of both worlds. I do plan on doing a dyno pull in a month or so so I can measure the difference, but the butt dyno says 20+ hp over 6000 rpm as she really pulls better with the exhaust open!
Old 07-02-08, 09:54 PM
  #8  
Eats, Sleeps, Dreams Rotary

iTrader: (1)
 
ultimatejay's Avatar
 
Join Date: Nov 2006
Location: California
Posts: 4,148
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by 84stock
I have a friend with a pp 13b second gen. I believe he uses Borla with the removable silencer. He says that having the silencer in kills about 20+ hp off the top end. Without the silencer it is loud as hell. My suggestion, follow what I have done. I run 2 presilencers and a magnaflow, very drivable. When I race I click the switch for an electric dump off the header (qtec). So i get the best of both worlds. I do plan on doing a dyno pull in a month or so so I can measure the difference, but the butt dyno says 20+ hp over 6000 rpm as she really pulls better with the exhaust open!
That's a good idea too. Could you post pics of your set up?
Old 07-02-08, 10:13 PM
  #9  
OLDROTA

Thread Starter
 
Jaime Enriquez's Avatar
 
Join Date: Apr 2003
Location: Los Angeles
Posts: 1,389
Likes: 0
Received 1 Like on 1 Post
This Aurotary thread has excellent info on building your own muffs.
http://ausrotary.com/viewtopic.php?f...&sd=a&start=80
Old 07-02-08, 11:53 PM
  #10  
Lives on the Forum

iTrader: (5)
 
84stock's Avatar
 
Join Date: Apr 2003
Location: calgary
Posts: 5,537
Likes: 0
Received 9 Likes on 5 Posts
Mines out of service due to a camden failure right now. When it is back in service I'll give a video of open and closed exhaust and pics. maybe video the qtec as well
Old 07-16-08, 10:58 AM
  #11  
Blood, Sweat and Rotors

iTrader: (1)
 
DriveFast7's Avatar
 
Join Date: Aug 2001
Location: California
Posts: 3,742
Received 1 Like on 1 Post
Put a 90* mandrel bent tailpipe on there. Making the exhaust turn nintey degrees quiets it down. Plus adding some pipe does too.
Old 07-17-08, 10:33 PM
  #12  
Junior Member
 
Team D.o.D's Avatar
 
Join Date: Jul 2008
Location: AZ
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
...
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
stickmantijuana
20B Forum
7
08-30-15 12:08 AM
GrossPolluter
General Rotary Tech Support
7
08-22-15 11:23 PM



Quick Reply: Muffling a P-Port



All times are GMT -5. The time now is 09:45 AM.