Honda Car Forum


Go Back   Honda Car Forum - Accord Parts Civic Tuning Acura Racing > Discussion > Acura Technical

LinkBack Thread Tools Display Modes
  #1 (permalink)  
Old 20 Aug 2007, 05:03 am
Jon Jon is offline
Senior Member
Join Date: Aug 2007
Posts: 142
Default whats the performance difference between 4-2-1 and 4-1 headers?

i know what they look like, i know what they do, i know how to put em in. im just not sure about the performance part. ive always used 4-2-1 just cuz it looks like the exhaust exits smoother. but which one is good for top-end, bottom-end, all-around etc. and do you think it matters what theyre coated with? ie ceramic, chrome, stainless steel
Reply With Quote
  #2 (permalink)  
Old 20 Aug 2007, 05:08 am
Junior Member
Join Date: Aug 2007
Posts: 6

4-2-1 header will give better all round performance because it will reduce pressure drop in the exhaust tract, however the amount of improvement depends on the rest of the engine, the type of cams used, if they have longer dwell angles as in full race cams then a bigger change over a 4-1 header will be seen. the coating is basically looks and extends the life but does nothing to help performance. If you have cams with long dwell angles the 4-1 header will cause some back flow of exhaust to the combustion chamber and reduce the amount of fuel and oxygen in the fresh charge to the combustion chamber
Reply With Quote
  #3 (permalink)  
Old 20 Aug 2007, 05:10 am
Junior Member
Join Date: Aug 2007
Posts: 1

You've got two choices: Accept what a particular header mfr states about their product's performance, or have a performance shop dyno test what you already have. In the real world of being the fastest badboy in the 'hood, 2-4 hp gain or loss is nothing compared to the ticket you'll probably get trying find out where the hp drops off...Chrome is always a good choice - Stainless is just overpriced chrome....
Reply With Quote
  #4 (permalink)  
Old 20 Aug 2007, 05:18 am
Senior Member
Join Date: Aug 2007
Posts: 139

Alright, so here is the main differences in a nutshell....The 4-2-1 is less free flowing and basically better for torque and lower end power.The 4-1 is much more free flowing and better for higher end power.For all-around performance, I guess it will all depend on what your going for. I desired a more free flowing exhaust when I was building my engine so I choose the 4-1. Plus, with the supercharger on my car providing excellent low-end power, I wanted the more free flowing exhaust to increase the higher-end.As for the different kinds of doesnt matter, the coatings dont affect the performance. The ceramic coat looks excellent under the hood (I have a ceramic coated DC header on my 00 Civic Si), the stainless steel header also looks great under the hood and due to the constant heating and cooling, the header actually changes colors, it looks neat but I prefer the ceramic coat.
Reply With Quote
  #5 (permalink)  
Old 20 Aug 2007, 05:28 am
Senior Member
Join Date: Aug 2007
Posts: 170

Reply With Quote

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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
whats the difference from a civic EK9 and a Spoon Civic? hooni_9 Honda Technical 2 18 Aug 2007 07:40 pm
Whats the difference between a sports car and a sporty car?? mikey212 Acura Technical 6 16 Aug 2007 10:16 am
Whats Unique about the 2000 Acura integra Special Edition? whats special about it? fabianoindustries Acura Technical 2 16 Aug 2007 06:06 am
whats the difference between an acura nsx and a honda nsx? Mike Acura Technical 10 16 Aug 2007 04:12 am
greddy headers Darren Acura 3 24 Mar 2005 11:24 am

All times are GMT -5. The time now is 04:24 pm.

Honda News | Autoblog
Powered by Yahoo Answers

Powered by vBulletin®
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
LinkBacks Enabled by vBSEO 3.6.0 PL2 © 2011, Crawlability, Inc. is not affiliated with Honda Motor Company in any way. Honda Motor Company does not sponsor, support, or endorse in any way. Copyright/trademark/sales mark infringements are not intended or implied.