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

what to hear from people with single and dual exhaust

Old Apr 21, 2003 | 08:37 AM
  #26  
projekt's Avatar
Rotary Enthusiast
Tenured Member 10 Years
 
Joined: Apr 2003
Posts: 757
Likes: 0
From: NW Arkansas
explain to me how a drivetrain takes away a percentage of torque rather than a (somewhat) constant amount.

Last edited by projekt; Apr 21, 2003 at 08:40 AM.
Reply
Old Apr 21, 2003 | 08:43 AM
  #27  
1987RX7guy's Avatar
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
You generally se a 15-20% drop in HP from the flywheel to the tires. I believe most of use agree on that.

Example: my 94 4-banger has about 117hp at the crank and about 95 at the tires. The amount of hp lost will be somewhere close to that 15-20% of hp lost number. Many of the TV shows that deal with modding and the performance of cars also use that % to explain the difference of the two HP values. Ofcoarse it will not always be true but it is a general number that fits most apps
Reply
Old Apr 21, 2003 | 08:55 AM
  #28  
projekt's Avatar
Rotary Enthusiast
Tenured Member 10 Years
 
Joined: Apr 2003
Posts: 757
Likes: 0
From: NW Arkansas
yeah but when you say 20% you mean stock. if you hold that 20% forever then a supra that dynos 800 can claim he makes 1000hp so somehow his drivetrain (with the only mod probably being a clutch) is somehow using 136 more hp than it was when the car was stock.
to find out what the bhp is it's pretty simple algebra

BHP - x = WHP

BHP(mod) - x = WHP(mod)
Reply
Old Apr 21, 2003 | 10:31 AM
  #29  
jasonw3579's Avatar
Full Member
Tenured Member 05 Years
 
Joined: Jan 2003
Posts: 132
Likes: 0
From: Carrollton, TX
the only problem with what you said about stock TIIs having 110hp to the wheels is that you took the amount of HP taken off from BCD's car with his 500 bhp and took the same amount off of the stock TII, it doesn't quite work like that
Reply
Old Apr 21, 2003 | 10:43 AM
  #30  
mazdaspeed7's Avatar
mad scientist
Tenured Member 10 Years
 
Joined: Feb 2001
Posts: 2,665
Likes: 2
From: Savannah, GA
1987rx7guy, you missed my whole point. You can still have a collected exhaust and dual mufflers. True duals refers to an exhaust that never collects. To put it simply, true duals arent really tuned. They make no use of the exhaust pulses to make more power. A collected exhaust does, and you can use a y pipe, and have 2 mufflers, and have flames come out both. A collected exhaust merges somewhere, but it does NOT have to be a single exhaust all the way back.

True duals sound like ****, and can never make as much power as a single. Im in the middle of making a new exhaust, and it will be collected in the middle, then split into a y pipe for 2 mufflers.
Reply
Old Apr 21, 2003 | 11:04 AM
  #31  
1987RX7guy's Avatar
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
Well for me to have gotten a tuned single with a y-pipe I would have to go to one of the idiot muffler shops here. I don't trust my father with my car do you think I would trust a mechanic. I don't know how to tune the exhaust buy collecting it in differend areas so I don't know how I could do it. Basically I bought the DUALS cuz they were 1) A complete setup 2) They were pretty damned good power 3) I did not have to fabricate anything myself.
What resulted was an easy instal, good performance jump, great sound(sound is qualitative not quantitative meaning it is an oppinion not a fact) and I get flames that come at slightly different times.
Reply
Old Apr 21, 2003 | 11:50 AM
  #32  
marcus219's Avatar
FC Mobsta
Tenured Member 15 Years
 
Joined: Sep 2002
Posts: 1,825
Likes: 2
From: Olympia, WA
Originally posted by j200pruf
Power Wise Dauls are not nearly as good as a large single (3.0 inch) for a turbo. PLus I thought turbos didn't throw flames like N/A's do. Go single.
Turbos usually throw huge flames compared to n/a's..not even on rotaries....big horsepower piston turbo engines usually have nice flames...I take it it b/c turbos run ALOT more fuel under booost...on decel there no boost so the acsess fuel is going to get dumped out the exhaust..BOOM
Reply
Old Apr 21, 2003 | 03:04 PM
  #33  
projekt's Avatar
Rotary Enthusiast
Tenured Member 10 Years
 
Joined: Apr 2003
Posts: 757
Likes: 0
From: NW Arkansas
Originally posted by jasonw3579
the only problem with what you said about stock TIIs having 110hp to the wheels is that you took the amount of HP taken off from BCD's car with his 500 bhp and took the same amount off of the stock TII, it doesn't quite work like that
please explain to me why it doesn't quite work like that?
Reply
Old Apr 21, 2003 | 08:10 PM
  #34  
projekt's Avatar
Rotary Enthusiast
Tenured Member 10 Years
 
Joined: Apr 2003
Posts: 757
Likes: 0
From: NW Arkansas
no answer?
Reply
Old Apr 21, 2003 | 08:32 PM
  #35  
RylAssassin's Avatar
Rotary Enthusiast
Tenured Member 10 Years
 
Joined: May 2002
Posts: 1,203
Likes: 0
From: Boston
If your starting out and just got a TII, with a not so good engine, Theres like a hundred diffrent options for you my freind. Now if you want to focus on exuast then defenetly consider getting a single exuast for the TII. There are so many more logical reasons for going single, and the main ones are the power gain and the wieght savings. In my opinion looks are not as imoprtant as power. You want the most out of your engine and turbo go single. The turbo spools so nicely with a single exaust but you have to watch the creep and mod your car the RIGHT way and know what your getting yourself into. Just as an example the BEST single set up ive ever seen was this dude with a 3" DP then to a JIC titanium exuast, its insane its 3" all the way back and super light. Little pricey (Like 1500) But holy **** what a system. Do research for the most part and youll see. Good luck
Reply
Old Apr 21, 2003 | 08:57 PM
  #36  
4thrx7's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Apr 2003
Posts: 19
Likes: 0
From: tampa florida
well the motor will deff. be pulled out, i'll blow it myself doing burn outs in front my house. that will be fun. turn up the wastegate and all the other cool shyt. i want to do a total s5 swap, before the s5 is dropped in i want it street ported and a larger to4 turbo, only question is FMIC ...and how much will this cost me on average what have u heard people spent on such a job.
Reply
Old Apr 21, 2003 | 09:02 PM
  #37  
projekt's Avatar
Rotary Enthusiast
Tenured Member 10 Years
 
Joined: Apr 2003
Posts: 757
Likes: 0
From: NW Arkansas
if you're going to go nuts on blowing an engine, be sure to tape it!
Reply
Old Apr 21, 2003 | 09:26 PM
  #38  
4thrx7's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Apr 2003
Posts: 19
Likes: 0
From: tampa florida
i will tape it
Reply
Old Apr 21, 2003 | 10:00 PM
  #39  
JAPSPECGTUs's Avatar
Turbo GTUs Est. 1999
Tenured Member 05 Years
 
Joined: Oct 2002
Posts: 794
Likes: 0
From: Los Angeles, CA (323)
Borla (straight cut tips) look sleepy and sound great. They are deep from 0-4k, after that you can't block a rotary's scream.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Skeese
Adaptronic Engine Mgmt - AUS
65
Mar 28, 2017 03:30 PM
LunchboxCritter
2nd Generation Specific (1986-1992)
15
Jan 3, 2016 04:11 PM


Thread Tools
Search this Thread

All times are GMT -5. The time now is 10:16 AM.