4-2-1 or 4-1

[MotoXracerfss]

after searching, i've found most results are people asking about certain headers.

So what are the differences in the 2 (4-2-1 and 4-1) types....advantages/disadvantages?

[egcivic95]

4-2-1 = low and mid gains and 4-1 = top end gains of hp

[christopher_davis]

^yep

[DirtyDC4]

Getting a 4-2-1 over a 4-1 should only be for 2 reasons:

-ground clearance
-if you have an EF, you don't have to remove your crossmember to install it

[MotoXracerfss]

thanks for the replies....how much more do you gain up top for 4-1?

[dhetz]

Getting a 4-2-1 over a 4-1 should only be for 2 reasons:

-ground clearance
-if you have an EF, you don't have to remove your crossmember to install it

is the crossmember can be pull out and then put again ? whats that mean of remove here

becoz i have problem with crossmember if i wanna use 4-1 long header like SMSP

[DirtyDC4]

"Remove" as in unbolt crossmember and put it off to the side, install header, re-install crossmember.

[remoer]

i would be glad to help you but here's mine. lol
http://i31.photobucket.com/albums/c356/remoer/exhaust.jpg

[MrHalder]

is the crossmember can be pull out and then put again ? whats that mean of remove here

becoz i have problem with crossmember if i wanna use 4-1 long header like SMSP

What? :confused:

[SOHCinWA]

IMO I like more top end power. But I like to keep the R's up. I like 4 into 1 the best. I dont care for power from idle to mid range. I want all the power from mid range to redline...
Don

[remoer]

IMO I like more top end power. But I like to keep the R's up. I like 4 into 1 the best. I dont care for power from idle to mid range. I want all the power from mid range to redline...
Don

it's funny here you say this cause i just had a conversation about this. in reference my build. lol.

[SOHCinWA]

My first header was an S&S (4into1) back in 88. I was hooked. Then when I went to work for Hotshot Performance , I designed one similar but made more power. So much more power that JG asked us to start building the same style but for the B motors in 1997. But there is no other header on the planet today that compares to the Bisimoto header. The new one is going to be SICK!!

[remoer]

i can't wait till see it, too.

[SOHCinWA]

Yeah, i have a few on order to sell through my shop too. Plus the one for my car.

[remoer]

make sure you post some pics fast.

[SOHCinWA]

As soon as I get them from UPS you all know they will be up for eveyone to drool over

[dhetz]

i would be glad to help you but here's mine. lol
http://i31.photobucket.com/albums/c356/remoer/exhaust.jpg

is that SMSP 4-1 header ? how about collector's diameter?how much

[remoer]

lol. that so true

[remoer]

is that SMSP 4-1 header ? how about collector's diameter?how much

if i'm measuring them correctly it's 2.5"m an ole skool ZR header and nope not for sale..... unless you have something to bring to table for trade.... don't ask me what i need, cause... well i'm not sure what i need. lol.

[hatchnthoughts]

is the crossmember can be pull out and then put again ? whats that mean of remove here

becoz i have problem with crossmember if i wanna use 4-1 long header like SMSP

sig material right here... good stuff lol

[88cr-rex]

I just recently switched from an EBAY 4-2-1 to a DC ceramic 4-1 and you can definetly tell a difference from 3500 up.

I do have an 88 CRX and it was a PITA. I ended up notching and boxing the subframe so the header will slide in without removing the subframe. You still have to loosen it but it is much easier than completely removing it.

Hopefully I will have some dyno sheets next week of before and after.
With the old header, the car made right at 105whp with a junk b2 motor.

[PSmurf78]

As soon as I get them from UPS you all know they will be up for eveyone to drool over

Any idea on the time frame?

[SOHCinWA]

I know that he told a couple days ago that he is just waiting on flanges and then its off to the races... I am waiting patienly just like everyone else.. Hopefully another couple weeks. Cant rush perfection though

[replica]

I could never tell a difference between 4-2-1 or 4-1. Most anything is better than stock.

[MotoXracerfss]

would be interesting to see dyno graphs between the 2

[gearhead98]

4-2-1 can be easier to install in a tight engine bay, and can give better ground clearance over a 4-1. i have a megan racing which is a 4-2-1. i love it, can def tell a difference over stock. as to were it makes its power low to mid or mid to high i dunno, i know it makes more power over stock

[jamisgood]

I have a 4-1 on mine and i love the pull it gives you up top.

[SOHCinWA]

4-2-1 can be easier to install in a tight engine bay, and can give better ground clearance over a 4-1. i have a megan racing which is a 4-2-1. i love it, can def tell a difference over stock. as to were it makes its power low to mid or mid to high i dunno, i know it makes more power over stock


The 2 peice is much easier of an install. But IMO the 4into1 is the way to go.

[mightyjoecivic]

I have a heddman 4-2-1 header and noticed a gain in the mid-range power.

[gearhead98]

mightyjoe im stealin your stage 1, let me know where i can pick it up :)

[mightyjoecivic]

aaaahhhhhhh! Go away thief!!! lol

[christopher_davis]

http://www.hadamotorsport.com/tech/review/dsemc/
a damn good link on headers

[Belette]

it depend on many things. We have some thread about that, and it talks about primary length and size, secondary the same, merges, and so many thing. But in my opinion if you want severe n/a, go with smp or bisimoto or something with strong high end, if not, go 4-2-1.

Difference between 'normal' 4-1/4-2-1 is around 2-4hp at the high range, and the biggest gain/lost is in midrange torque.

[MotoXracerfss]

Thanks everyone!

[jmar504]

i had a 4-2-1 header on my car.. but i heard that 4-1 are better so i bought one and it is better i think... ...pulls harder from like 4500 and up... alot harder.. but i scrape everywhere... thats the down fall... but its worth it..

[kulo]

421 sits lower than 4-1 right

[8 valve drew]

no. 4-2-1 will hug the block closely, and not scrape as much as a 4-1

[DirtyDC4]

no. 4-2-1 will hug the block closely, and not scrape as much as a 4-1

Hug the oil pan more, but you got the right idea. :TU:

[dante_d15]

I just got a custom header 4-2-1.. it works nice for low gains..
I never had a 4-1 header so i can't say a difference for top ends or redline

[gearhead98]

yeah a 4-1 has to be a lil broader so that you can still install it, the 4-2-1 doesn't because its in 2 pieces.