AcuraLegend.Org - The Acura Legend Forum for All Generations of the Honda / Acura Legend; 1986 to Present  

Go Back   AcuraLegend.Org - The Acura Legend Forum for All Generations of the Honda / Acura Legend; 1986 to Present > Second Generation Legend -- 1991 - 1995 > 2nd Gen. Legend Performance Enhancements

Reply
 
Thread Tools Display Modes
Old 09-11-2011, 06:44 PM   #1
GreenHornet Legend
Junior Member
 
Join Date: Jun 2011
Location: Arizona
Posts: 94

GreenHornet Legend is on a distinguished road
Default 3in exhaust on a mostly stock engine

I was looking for an answer but I think I already now it. I was wondering if I can put a 3in exhaust pipe from where the pipes join together all the way back to the muffler? I was wondering because I plan on turbo charging the car later but I don't really know the science behind the exhaust. Is it ok to do this or will I lose power doing this to a stockish engine. I would then modify the pipe later to accommodate the turbo.
__________________
Synergy Green Legend
GreenHornet Legend is offline   Reply With Quote
Old 09-11-2011, 06:53 PM   #2
Gascan
Less doom less gloom
 
Gascan's Avatar
 
Join Date: Jun 2009
Location: Sunshine State, away from rain...
Posts: 1,843

Real Name: Michael K.
Gascan is a jewel in the roughGascan is a jewel in the roughGascan is a jewel in the rough
Default

Quote:
Originally Posted by GreenHornet Legend View Post
I was looking for an answer but I think I already now it. I was wondering if I can put a 3in exhaust pipe from where the pipes join together all the way back to the muffler? I was wondering because I plan on turbo charging the car later but I don't really know the science behind the exhaust. Is it ok to do this or will I lose power doing this to a stockish engine. I would then modify the pipe later to accommodate the turbo.
Seems to me that you're working on this backwards. Start with turbo then modify the exhaust to accommodate the turbo.

Yes, you'll loose major power with a stockish engine.
Gascan is offline   Reply With Quote
Old 09-11-2011, 07:02 PM   #3
Geneva_Jee
Gold Member
 
Geneva_Jee's Avatar
 
Join Date: Mar 2010
Location: So Cal
Posts: 3,481



Geneva_Jee will become famous soon enough
Default

N/A engines need back pressure...a 3in exhaust on a stock motor will make it lose power
__________________
"If you're good at something, never do it for free."

FOR SALE - Geneva KA7 Sedan In Memory of
Geneva_Jee is offline   Reply With Quote
Old 09-12-2011, 02:40 AM   #4
hustlav6
Banned
 
Join Date: Jun 2010
Location: Poland
Posts: 904

hustlav6 is on a distinguished road
Default

pipes length and diameter are calculated to help empty the cylinders at exhaust stroke, if you alter any of exhaust dimensions without checking (by calculations) what effect you achieve - sonic or dynamic, you will be surprised that your engine seem to give you less power than it should, probably you will gain some hp in certain (probably high)rpm range, but it will be useless in daily driving, generally in n/a engines the bigger exhaust piping is, the higher engine revs would be needed to use gained power
hustlav6 is offline   Reply With Quote
Old 09-12-2011, 03:06 AM   #5
T-Clyde
Canter-Buried Alive
 
T-Clyde's Avatar
 
Join Date: Jun 2009
Location: Corganville
Posts: 4,125

Real Name: Tommy
T-Clyde is a jewel in the roughT-Clyde is a jewel in the roughT-Clyde is a jewel in the roughT-Clyde is a jewel in the rough
Default

Where's grumpysteelman when you need him? Smh

Hustla is on the right track, but grumpy is soo good at explaining the back pressure myth.
__________________
Quote:
Originally Posted by Captain Slow View Post
First step to being treated like a human being is to act like a human being.
OEM Parts for Sale
RIP
Maintenance > Modification
T-Clyde is offline   Reply With Quote
Old 09-12-2011, 06:34 PM   #6
legend93g2
Improving WHP
 
legend93g2's Avatar
 
Join Date: Sep 2009
Location: Broward, Florida
Posts: 2,980

legend93g2 is on a distinguished road
Send a message via Yahoo to legend93g2
Default

Quote:
Originally Posted by Geneva_Jee View Post
N/A engines need back pressure...a 3in exhaust on a stock motor will make it lose power
This +1
__________________
[/CENTER]DYNOJET: 218.83WHP 195.28Torque
http://www.youtube.com/watch?v=xwfR-Pl4M50
MOD List: http://forums.acuralegend.org/garage...vehicle&id=371
legend93g2 is offline   Reply With Quote
Old 09-12-2011, 06:38 PM   #7
GreenHornet Legend
Junior Member
 
Join Date: Jun 2011
Location: Arizona
Posts: 94

GreenHornet Legend is on a distinguished road
Default

So the same reasoning applies to headers?
__________________
Synergy Green Legend
GreenHornet Legend is offline   Reply With Quote
Old 09-12-2011, 06:52 PM   #8
ManOfBusiness
My Penis Has A Name
 
ManOfBusiness's Avatar
 
Join Date: Jun 2009
Location: Houston, Tx
Posts: 3,439

ManOfBusiness is a jewel in the roughManOfBusiness is a jewel in the roughManOfBusiness is a jewel in the roughManOfBusiness is a jewel in the rough
Default

Cars with small displacement lose bottom end torque because they have to overcome the pressure of slower moving exhaust gasses in large diameter piping.

Larger displacement engines capitalize on a larger exhaust setup because as someone said previously their engines can use this increase in potential airspace, with more displacement, you have more exhaust gasses which increases the use of the gained potential air space.

Realistically, and engine under 3 litres N/A would not benefit from an increase in exhaust or header piping over stock, however its the gain in increased flow potential due to more efficient pipe flow design.
__________________
-Some things never change, and some things do-
ManOfBusiness is offline   Reply With Quote
Old 09-12-2011, 07:18 PM   #9
T-Clyde
Canter-Buried Alive
 
T-Clyde's Avatar
 
Join Date: Jun 2009
Location: Corganville
Posts: 4,125

Real Name: Tommy
T-Clyde is a jewel in the roughT-Clyde is a jewel in the roughT-Clyde is a jewel in the roughT-Clyde is a jewel in the rough
Default

Quote:
Originally Posted by ManOfBusiness View Post
Cars with small displacement lose bottom end torque because they have to overcome the pressure of slower moving exhaust gasses in large diameter piping.

Larger displacement engines capitalize on a larger exhaust setup because as someone said previously their engines can use this increase in potential airspace, with more displacement, you have more exhaust gasses which increases the use of the gained potential air space.

Realistically, and engine under 3 litres N/A would not benefit from an increase in exhaust or header piping over stock, however its the gain in increased flow potential due to more efficient pipe flow design.
I have to disagree, and this is directly related to accords of my generation. They all share the same 2.2 l block, but the dx and lx have smaller exhaust and a cast manifold, where as the ex has a tubular manifold and 1/4 larger piping all the way back, stock for stock the ex has 10 more hp and the only differences are the larger exhaust and slightly larger intake mani.

You don't lose torque, you simply move the peak torque higher in the powe band.
__________________
Quote:
Originally Posted by Captain Slow View Post
First step to being treated like a human being is to act like a human being.
OEM Parts for Sale
RIP
Maintenance > Modification
T-Clyde is offline   Reply With Quote
Old 09-12-2011, 07:29 PM   #10
ManOfBusiness
My Penis Has A Name
 
ManOfBusiness's Avatar
 
Join Date: Jun 2009
Location: Houston, Tx
Posts: 3,439

ManOfBusiness is a jewel in the roughManOfBusiness is a jewel in the roughManOfBusiness is a jewel in the roughManOfBusiness is a jewel in the rough
Default

Great... thanks for the input... please note I said bottom end torque. and whether you realize it or not, you're agreeing with me.
__________________
-Some things never change, and some things do-

Last edited by ManOfBusiness; 09-12-2011 at 07:32 PM.
ManOfBusiness is offline   Reply With Quote
Reply

Bookmarks

Tags
3 inch pipe, big pipe, exhaust, horsepower, turbo


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
My Stock IS-F Dv8 Videos 28 08-03-2012 02:39 PM
Engine Replacement... What to change while the engine is out? pacallen 1st Gen. Legend General Discussion 5 07-31-2010 08:52 PM
stock exhaust manifold question uniquelegend 1st Gen. Legend General Discussion 4 12-28-2009 01:50 PM
engine crank and won't start engine check light Legend95 2nd Gen. Legend General Discussion 0 12-22-2009 06:59 AM
stock exhaust + high flow cat sound? hotstartup 2nd Gen. Legend General Discussion 4 08-25-2009 06:00 AM


All times are GMT -7. The time now is 01:26 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.

AcuraLegend.Org is not affiliated with, nor represents in any form, Acura and Honda Motor Company. Some logos and names used herein remain the trademark of Honda Motor Company.