4-2-1 exaust? or 4-1 ??

team dragstar · 1st June 2006, 22:01

guyz what do you think what exaust headers are better for honda's 4-2-1 or 4-1... just a debate ....

The Wolf · 1st June 2006, 23:59

Welcome to the forum team Dragster...Kindly go through the forum rules and start your posting with a brief intro...

Talking about the type of header for Honda...it depends on the purpose coz the header designs vary from drag usage to street racing to track racing. 4x2x1 is preferred for low and sharp mid range where as 4x1 is mostly for sharp peak rpm boost.

But there are hybrid headers today with narrow and extended primaries and secondaries in 4x2x1 with large collector cones...this design is supposed to give the best of both worlds.

Its believed that 4x2x1's do a better job in comparison to 4x1's on small engines i.e under 1.6- 1.8litre.

Headers can be tuned to a particular rpm band or peak rpms...so its the purpose of usage thats imp before considering the type. A good header is a purpose built one (by someone who knows it well) and not the mass production ones, remmember that.

viper · 2nd June 2006, 08:24

Hey Wolf,

Spot on man could not have explained it better. At least know people will understand why I say that Automech is not the best. His free flows are mass manufactured without taking a customers requirements(other than sound) into consideration which may not be suited for say a modded engine. Am not saying they dont perform, but you can get a lot more by properly calculated and designed free flows. Anyways majority of cutomers do not know what they want or what they can get and hence are happy with their results as it is an improvement over the stock car.

Viper

Shan2nu · 2nd June 2006, 08:42

This site will explain everything in detail. Read on....

http://www.team-integra.net/sections...sp?ArticleID=2

Shan2nu

ghostrider4385 · 2nd June 2006, 10:58

Hey Shan2nu... that was a really informative link. Cleared a lot of q's I had!

Godspeed.

Alok.

speedsatya · 2nd June 2006, 16:35

Quote:

Originally Posted by viper

Hey Wolf,

Spot on man could not have explained it better. At least know people will understand why I say that Automech is not the best. His free flows are mass manufactured without taking a customers requirements(other than sound) into consideration which may not be suited for say a modded engine. Am not saying they dont perform, but you can get a lot more by properly calculated and designed free flows. Anyways majority of cutomers do not know what they want or what they can get and hence are happy with their results as it is an improvement over the stock car.

Viper

hey ...why is it that everytime an exhaust topic comes up ..you dont forget to mention Automech ...

viper · 2nd June 2006, 16:58

Quote:

Originally Posted by speedsatya

hey ...why is it that everytime an exhaust topic comes up ..you dont forget to mention Automech ...

Hi,

Because he is advertised/promoted here as the best which he is not. I believe this forum is a place to educate and tell people of the various options available so that they can make their own choice and not go by the most popular.

Lets not argue on this as I am not here to promote anyone but at the same time will not let people who are unaware of the pro's & cons get fooled into believing Automech is the best.

Viper

mclaren1885 · 2nd June 2006, 17:24

I certainly agree to wolf and viper regarding to the automech exhausts .. None of them are specifically tuned according to ur taste, which could potentially cause damage to a modded engine .. Well i also know some guy who made headers for a friends car of mine that kicked in at 1500 rpm ?? I mean what was he thinking off ?? Starting a towing service ??

ajmat · 2nd June 2006, 19:14

Note from Mod

Am not sure where this thread is going. Topic is 4 into 1 or 4 into 2 into 1. Discuss this.

If one wants to discuss Automech system con's - start another thread and please ensure you have facts and direct information ie

Actual BHP improvement, drivability etc

If automech ain't the best, who is...and why, complete with facts.

Please note that none of mod team have anything to do with automech. This is a response due to multiple feedback

team dragstar · 2nd June 2006, 19:26

guys i think there is only one guy in mumbai who can actually make good custom exaust and that is merit exaust systems
great stainless steel work!!!!

jkdas · 11th June 2006, 16:13

POints I found which should be looked at when going for a freeflow exhaust system. (the link given in the post below). Do comment.

1) Longer , smaller diameter collectors have more power in the midrange. ; what I would liek to have. Why? In highway drive, you need midrange..right?

2)ignition firing order determines which exhaust pulses leave in a particular order. ... emm, think I will need a Sequential pairing.

3) CAn someone explain this ... "Do you want peak torque to be at a lower rpm ? Do you prefer big hp in the last 3000 rpms of your rev range? Do you need both? Look at the header design characteristics to determine which header has the right layout for the power curve shape you want."

4) and these exhaust designs... straight-through ,2 pass, twin loop, or sound-cancellation design, chambered. Which are street legal of these? Are chambered the one's we have as OE?

5) I want a smaller muffler with some short resonator pipe( not too loud), donno about holes/louvers, a good tip, and straight through or 2 pass

, with condition 1 and 2.

I have a Xing.

Was my order right?

buzzin_hornets · 19th June 2006, 04:21

Quote:

Originally Posted by team dragstar

guys i think there is only one guy in mumbai who can actually make good custom exaust and that is merit exaust systems
great stainless steel work!!!!

where is he located? pm his number, amitabh..

team dragstar · 20th June 2006, 14:04

buzzin .. you could contact a r motorsport ranjeet on9869045084
he should be able to help you out

jkdas · 27th June 2006, 11:56

Another doubt.

Can one get a custom header and use it with the OE exhausts?

Is it ok to remove muffler and exchange it with a straight pipe..

dhananjay · 28th August 2006, 09:29

what difference does it make in 4:2:1 & 4:1 header is it some difference in performance and power?

Note from Mod - Threads merged.
Please try and use the search feature before creating a new thread. (Thanks for the link Shan2nu)

1st June 2006, 22:01	#1
team dragstar BHPian Join Date: May 2006 Location: mumbai Posts: 80 Thanked: 0 Times View My Garage	4-2-1 exaust? or 4-1 ?? guyz what do you think what exaust headers are better for honda's 4-2-1 or 4-1... just a debate ....
	() Thanks

1st June 2006, 23:59	#2
The Wolf Senior - BHPian Join Date: Jan 2005 Location: Bangalore Posts: 1,120 Thanked: 75 Times	Welcome to the forum team Dragster...Kindly go through the forum rules and start your posting with a brief intro... Talking about the type of header for Honda...it depends on the purpose coz the header designs vary from drag usage to street racing to track racing. 4x2x1 is preferred for low and sharp mid range where as 4x1 is mostly for sharp peak rpm boost. But there are hybrid headers today with narrow and extended primaries and secondaries in 4x2x1 with large collector cones...this design is supposed to give the best of both worlds. Its believed that 4x2x1's do a better job in comparison to 4x1's on small engines i.e under 1.6- 1.8litre. Headers can be tuned to a particular rpm band or peak rpms...so its the purpose of usage thats imp before considering the type. A good header is a purpose built one (by someone who knows it well) and not the mass production ones, remmember that.
	() Thanks

2nd June 2006, 08:24	#3
viper BANNED Join Date: Mar 2005 Location: Mumbai Posts: 1,773 Thanked: 20 Times	Hey Wolf, Spot on man could not have explained it better. At least know people will understand why I say that Automech is not the best. His free flows are mass manufactured without taking a customers requirements(other than sound) into consideration which may not be suited for say a modded engine. Am not saying they dont perform, but you can get a lot more by properly calculated and designed free flows. Anyways majority of cutomers do not know what they want or what they can get and hence are happy with their results as it is an improvement over the stock car. Viper Last edited by viper : 2nd June 2006 at 08:25.
	() Thanks

2nd June 2006, 08:42	#4
Shan2nu Senior - BHPian Join Date: Feb 2004 Location: Hubli - Karnata Posts: 5,533 Thanked: 125 Times View My Garage	This site will explain everything in detail. Read on.... http://www.team-integra.net/sections...sp?ArticleID=2 Shan2nu
	() Thanks

2nd June 2006, 10:58	#5
ghostrider4385 BHPian Join Date: Dec 2005 Location: Hyderabad Posts: 389 Thanked: 12 Times	Hey Shan2nu... that was a really informative link. Cleared a lot of q's I had! Godspeed. Alok.
	() Thanks

2nd June 2006, 17:24	#8
mclaren1885 BANNED Join Date: Jul 2005 Location: Bangalore (the city of modded cars) !! Posts: 4,820 Thanked: 46 Times View My Garage Infractions: 0/1 (10)	I certainly agree to wolf and viper regarding to the automech exhausts .. None of them are specifically tuned according to ur taste, which could potentially cause damage to a modded engine .. Well i also know some guy who made headers for a friends car of mine that kicked in at 1500 rpm ?? I mean what was he thinking off ?? Starting a towing service ??
	() Thanks

2nd June 2006, 19:14	#9
ajmat Team-BHP Support Join Date: Feb 2004 Location: Bangalore Posts: 15,061 Thanked: 29,717 Times View My Garage	Note from Mod Am not sure where this thread is going. Topic is 4 into 1 or 4 into 2 into 1. Discuss this. If one wants to discuss Automech system con's - start another thread and please ensure you have facts and direct information ie Actual BHP improvement, drivability etc If automech ain't the best, who is...and why, complete with facts. Please note that none of mod team have anything to do with automech. This is a response due to multiple feedback
	() Thanks

2nd June 2006, 19:26	#10
team dragstar BHPian Join Date: May 2006 Location: mumbai Posts: 80 Thanked: 0 Times View My Garage	guys i think there is only one guy in mumbai who can actually make good custom exaust and that is merit exaust systems great stainless steel work!!!!
	() Thanks

11th June 2006, 16:13	#11
jkdas Senior - BHPian Join Date: Sep 2005 Location: Thiruvananthapu Posts: 9,687 Thanked: 1,493 Times View My Garage	POints I found which should be looked at when going for a freeflow exhaust system. (the link given in the post below). Do comment. 1) Longer , smaller diameter collectors have more power in the midrange. ; what I would liek to have. Why? In highway drive, you need midrange..right? 2)ignition firing order determines which exhaust pulses leave in a particular order. ... emm, think I will need a Sequential pairing. 3) CAn someone explain this ... "Do you want peak torque to be at a lower rpm ? Do you prefer big hp in the last 3000 rpms of your rev range? Do you need both? Look at the header design characteristics to determine which header has the right layout for the power curve shape you want." 4) and these exhaust designs... straight-through ,2 pass, twin loop, or sound-cancellation design, chambered. Which are street legal of these? Are chambered the one's we have as OE? 5) I want a smaller muffler with some short resonator pipe( not too loud), donno about holes/louvers, a good tip, and straight through or 2 pass , with condition 1 and 2. I have a Xing. Was my order right? Last edited by jkdas : 11th June 2006 at 16:19.
	() Thanks

20th June 2006, 14:04	#13
team dragstar BHPian Join Date: May 2006 Location: mumbai Posts: 80 Thanked: 0 Times View My Garage	buzzin .. you could contact a r motorsport ranjeet on9869045084 he should be able to help you out
	() Thanks

27th June 2006, 11:56	#14
jkdas Senior - BHPian Join Date: Sep 2005 Location: Thiruvananthapu Posts: 9,687 Thanked: 1,493 Times View My Garage	Another doubt. Can one get a custom header and use it with the OE exhausts? Is it ok to remove muffler and exchange it with a straight pipe..
	() Thanks

28th August 2006, 09:29	#15
dhananjay BHPian Join Date: Aug 2006 Location: mumbai Posts: 29 Thanked: 2 Times View My Garage	what difference does it make in 4:2:1 & 4:1 header is it some difference in performance and power? Note from Mod - Threads merged. Please try and use the search feature before creating a new thread. (Thanks for the link Shan2nu) Last edited by Rehaan : 29th August 2006 at 04:23.
	() Thanks