Team-BHP (https://www.team-bhp.com/forum/)

-   Modifications & Accessories (https://www.team-bhp.com/forum/modifications-accessories/)

-   -   4-2-1 exaust? or 4-1 ?? (https://www.team-bhp.com/forum/modifications-accessories/13858-4-2-1-exaust-4-1-a.html)

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

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.

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

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

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

Shan2nu

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

Godspeed.

Alok.

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

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 ??

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

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!!!!

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 :D, with condition 1 and 2.

I have a Xing.

Was my order right?

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

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

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..

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)