2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

True dual exhaust, bad idea?

Thread Tools
 
Search this Thread
 
Old Jun 3, 2016 | 12:26 AM
  #1  
2jzfc's Avatar
Thread Starter
LegacyCore
 
Joined: Dec 2014
Posts: 259
Likes: 1
From: Rogersville, MO
MO True dual exhaust, bad idea?

And I'm not talking about RB's dual exhaust system. Thinking about making my own. I havr an RB header I'd like to modify, then make an exhaust that has seperate piping coming off esch exhaust port. Each bank will have an approved resonator and muffler to help with some of the harshness and db level.

My only thought against this is each bank will have only one pulse being that there are only two exhaust ports. And not 3-6 per bank depending on the engine. I figured the main reason the RB system works is the pre-silencer and their mufflers.

But I cannot find any examples on Youtube other than the RB system. Which leads me to think it's a not so great idea, or else a lot more people would be doing it.

Thought?
Reply
Old Jun 3, 2016 | 12:54 AM
  #2  
Brian Deane's Avatar
Full Member
 
Joined: Oct 2015
Posts: 224
Likes: 0
From: jacksonville, NC
itll either sound like a subie, 2 stroke or its ported...worth a try lol you can try to make UEL headers but ive never heard anything about them on a rotary kinda curious to what it would sound like

Last edited by Brian Deane; Jun 3, 2016 at 01:23 AM.
Reply
Old Jun 3, 2016 | 08:10 AM
  #3  
roTAR needz fundZ
Tenured Member 15 Years
iTrader: (1)
 
Joined: Aug 2002
Posts: 2,614
Likes: 31
From: Freeland, MI
Unless you get good mufflers, it will be loud
Reply
Old Jun 3, 2016 | 08:47 AM
  #4  
PinkRacer's Avatar
Licensed Zip Tie Mechanic
Tenured Member 15 Years
 
Joined: May 2004
Posts: 510
Likes: 2
From: Halifax, NS
Mine is the RB true dual with no presilencer - just the mufflers - Full Bridge, N/A:





Last edited by PinkRacer; Jun 3, 2016 at 08:58 AM.
Reply
Old Jun 3, 2016 | 08:50 AM
  #5  
PinkRacer's Avatar
Licensed Zip Tie Mechanic
Tenured Member 15 Years
 
Joined: May 2004
Posts: 510
Likes: 2
From: Halifax, NS
I should note that it it seems it actually makes more power as a single long tube collector, so we're going to be ditching the true dual system - not because of noise, but we want more power.

Last edited by PinkRacer; Jun 3, 2016 at 08:59 AM.
Reply
Old Jun 3, 2016 | 01:06 PM
  #6  
Dak's Avatar
Dak
Information Regurgitator
Tenured Member: 25 Years
Liked
Loved
Community Favorite
 
Joined: Feb 2001
Posts: 1,994
Likes: 208
From: Sparta TN. United States
From what I've read on here and mostly in the n/a performance section. The true dual or uncollected setup you describe works good on a car with stock ports. If the engine has any kind of port then something collected is better. Where to collect it is the question. Supposedly the RB streetable header is not optimum. Primaries are too long for a short primary system and too short for a long primary. Seems most that do a long primary collect them somewhere around the rear axle then to a single out. Run either the RB pre-silencer from their true dual system or something else that can take the heat as you mentioned as a pre-silencer of some sort. To find the optimum place to collect requires testing various collection points on the dyno.

Here is a link to RB's recommended starting points for primary length: Rotary Tech Tips: Exhaust System Configurations
Reply
Old Jun 3, 2016 | 01:09 PM
  #7  
Dak's Avatar
Dak
Information Regurgitator
Tenured Member: 25 Years
Liked
Loved
Community Favorite
 
Joined: Feb 2001
Posts: 1,994
Likes: 208
From: Sparta TN. United States
Originally Posted by PinkRacer
I should note that it it seems it actually makes more power as a single long tube collector, so we're going to be ditching the true dual system - not because of noise, but we want more power.
That would sound about right. Seems that as the port gets bigger with bridging or peripheral ports the primaries get shorter. Which is also reflected in the link above.
Reply
Old Jun 3, 2016 | 01:55 PM
  #8  
PinkRacer's Avatar
Licensed Zip Tie Mechanic
Tenured Member 15 Years
 
Joined: May 2004
Posts: 510
Likes: 2
From: Halifax, NS
Originally Posted by Dak
From what I've read on here and mostly in the n/a performance section. The true dual or uncollected setup you describe works good on a car with stock ports. If the engine has any kind of port then something collected is better. Where to collect it is the question. Supposedly the RB streetable header is not optimum. Primaries are too long for a short primary system and too short for a long primary. Seems most that do a long primary collect them somewhere around the rear axle then to a single out. Run either the RB pre-silencer from their true dual system or something else that can take the heat as you mentioned as a pre-silencer of some sort. To find the optimum place to collect requires testing various collection points on the dyno.

Here is a link to RB's recommended starting points for primary length: Rotary Tech Tips: Exhaust System Configurations
Yeah that's pretty much in line with what we're going to do - Collected near the rear axle, then likely a Borla: https://www.borla.com/products/xr1_m...t__400373.html
Reply
Old Jun 3, 2016 | 02:20 PM
  #9  
Brian Deane's Avatar
Full Member
 
Joined: Oct 2015
Posts: 224
Likes: 0
From: jacksonville, NC
ooo i like that borla
Reply
Old Jun 3, 2016 | 03:52 PM
  #10  
2jzfc's Avatar
Thread Starter
LegacyCore
 
Joined: Dec 2014
Posts: 259
Likes: 1
From: Rogersville, MO
Great info guys, and thank for the video reference I'm street ported so I might just keep the single with collecting at the axle. Then out to two separate mufflers.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
misterstyx69
2nd Generation Specific (1986-1992)
13
Apr 28, 2016 06:50 PM




All times are GMT -5. The time now is 02:25 AM.