Whats Better? Header 4-2-1 Or 4-1

[hondacivicnos]

Yea whats better 4-2-1 or 4-1?
And I heard that some of 4-1 are for Drag racing use.
But I have a B18C engine and I want 4-1 if it will work better than HEADER 4-2-1

 

[E_SolSi]

depends what you want .... a 4-2-1 will give you a little more mid range power... a 4-1 will produce more peak power

 

[Prowler]

I've heard 4-2-1 for NA and 4-1 for FI.

 

[rsaeini]

Originally posted by Prowler@Apr 16 2003, 02:17 PM
I've heard 4-2-1 for NA and 4-1 for FI.

Prowler, that isn't always true...

here's my understanding of the difference...

4-1 = top end power = generally for a more highly tuned engines that are making a lot of there power on the top end

4-2-1 = mid-range power = for more mildly tuned cars with basic bolt-ons because the mid-range power is more usable in a street application

if you run a 4-1 header on a engine with basic bolt-ons you'll get some lag in power on the low to mid range, you'll get some good top end power but it doesn't really have that kick on the lower part of the power band.

 

[ekPhred]

I also heard what Prowler was saying, I guess you learn something new everyday.

 

[Viperlocc_B18C1]

i had 4-2-1 headers on my b18c1 and i switched to th 4-1. the 4-2-1 are great if you like taking off from every light and taking people off the jump..but it lacks power closer to top end. with the 4-1, its more used for launching at higher rpm's so its right there. if you do a roll on with the 4-1 youll notice lag. the 4-2-1 dont lag.

 

[GSRCRXsi]

whats the difference in top end power thats produced? is enough to sacrafice the low end power for? cause i assumed a race was all about a good launch

 

[rsaeini]

here's a dyno graph of the 2 types in a head to head comparison...

*NOTE*-the 4-1 header that was used was ported so it's not a fair comparison. the red line is the 4-2-1 and the blue line is the 4-1. notice that you get better power on the low and mid-range on the 4-2-1. also notice the big dip you see on the 4-1 around the middle of the power band. you can make your own conclusions from this but this supports what i was saying.

header comparison

 

[Civic98HB]

will I see any difference on the high way speeds between 4-2-1 and 4-1.
And what do u mean top end what RPM, I am not going to bring it up to 7000 RPM so whats better for me?

 

[rsaeini]

according to that chart I linked, you'll get better power out of the 4-1 header past 6000rpms. if you're going to keep your revs below 7K then just go with the 4-2-1 cuz you get better power in the mi-range.

LOW-end = 1000-3500 rpms
MID-range = 3500-5500 rpms
TOP-end = 5500 rpms and up

 

[Civic98HB]

thanks

 

[OldSchoolSwap]

Originally posted by rsaeini@Apr 18 2003, 10:29 AM
LOW-end = 1000-3500 rpms
MID-range = 3500-5500 rpms
TOP-end = 5500 rpms and up

According to that low/mid/top graph, ain't it better for a vtec head to have a 4-1 header since we all race in vtec mode anyway (witch is above 4500 rpm). Low end and most mid range power will be used in first gear only. Once you keep the rpms high enough, each additional gear will be in the "top end" mode wouldn't it?
So according to this conclusion the 4-1 is a better choice over the 4-2-1 right?

Sorry to stir things up but it makes some sort of point, agree?

 

[rsaeini]

those number i gave are approx and if we're talking strictly in a race application, then yes.
check out this site, it'll answer all your questions:
http://www.hondalife.com/articles/bseriesheader.htm

 

[OldSchoolSwap]

Good article, thanks!