greddy 2.25 421 or jdm oem 4-1 2.5 header??
07-14-2003, 03:39 PM
#1
Thread Starter
Join Date: May 2002
Location: ny
Posts: 838
Likes: 0
Received 0 Likes
on
0 Posts
greddy 2.25 421 or jdm oem 4-1 2.5 header??
im thinkin about either the greddy 2.25 (i think anyone know?) 421 or jdm oem 4-1 2.5 header.. i have a dunk exhaust with 60mm piping which is 2.36 inch... so would it be better to get the greddy 2.25 inch with a 2.25 cat into the exhaust or the jdm 4-1 2.5 into a 2.5 cat into the 2.36 exhaust.. just wondering... also im gettin the greddy header for like 310 shipped .. thanks
07-14-2003, 06:02 PM
#2
Honda-Tech Member
Join Date: Jul 2001
Location: knee deep in the dead
Posts: 4,529
Likes: 0
Received 0 Likes
on
0 Posts
Re: greddy 2.25 421 or jdm oem 4-1 2.5 header?? (1hotintegra)
depends if you want more midrange power availability or want more top end? but as for me, id go with the JDM 4-1 if i had to choose between those two.
07-14-2003, 07:35 PM
#4
Honda-Tech Member
Join Date: Mar 2001
Location: VB, VA, USA
Posts: 835
Likes: 0
Received 0 Likes
on
0 Posts
Re: greddy 2.25 421 or jdm oem 4-1 2.5 header?? (1hotintegra)
JDM 4-1 
I have had both headers. The GReddy will feel strong in the mid-range, but I feel that your money would be better spent on the JDM 4-1 if you intend to build-up NA.
I have had both headers. The GReddy will feel strong in the mid-range, but I feel that your money would be better spent on the JDM 4-1 if you intend to build-up NA.
07-14-2003, 10:34 PM
#6
Thread Starter
Join Date: May 2002
Location: ny
Posts: 838
Likes: 0
Received 0 Likes
on
0 Posts
Re: greddy 2.25 421 or jdm oem 4-1 2.5 header?? (Cro-Mag)
but then its gunna get bottlenecked when it goes into the 2.36 piping from the catback... header 2.5 cat 2.5 exhaust 2.36 its not gunna flow good
Trending Topics
07-15-2003, 08:55 AM
#9
Honda-Tech Member
Re: greddy 2.25 421 or jdm oem 4-1 2.5 header?? (1hotintegra)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">
but then its gunna get bottlenecked when it goes into the 2.36 piping from the catback... header 2.5 cat 2.5 exhaust 2.36 its not gunna flow good
</TD></TR></TABLE>
fyi - the greddy has a 2" collector. There are no true 2.25" collectors for our cars because they are designed to matte up with the stock cat (which has a 2.0" inlet).
The only situation where you want inconsistant exhaust diameter is when you increase the diameter slightly as you get further away from the engine. This is called stepping and prevents exhaust reversion.
but then its gunna get bottlenecked when it goes into the 2.36 piping from the catback... header 2.5 cat 2.5 exhaust 2.36 its not gunna flow good
</TD></TR></TABLE>
fyi - the greddy has a 2" collector. There are no true 2.25" collectors for our cars because they are designed to matte up with the stock cat (which has a 2.0" inlet).
The only situation where you want inconsistant exhaust diameter is when you increase the diameter slightly as you get further away from the engine. This is called stepping and prevents exhaust reversion.
07-15-2003, 08:55 AM
#10
Re: (coyotes fan)
by his signature, i think he's running GSR.
whichever you decide, i woudl suggest getting a one peice instead of two.
I am installing a 4-2-1 Greddy one peice header next weekend.
whichever you decide, i woudl suggest getting a one peice instead of two.
I am installing a 4-2-1 Greddy one peice header next weekend.
07-15-2003, 03:33 PM
#12
Honda-Tech Member
Join Date: Jan 2002
Location: 54° 57’ 05”N 7° 44’ 13"W Europe.
Posts: 3,872
Likes: 0
Received 0 Likes
on
0 Posts
I have the DC JDM 4-1 with a mugen exhaust which has 2.38" piping, under 3k the car feels a little weak, but above it pulls way stronger than my friends car which has an unknown brand (possibly HKS) JDM 4-2-1 (2.5" collector)header with the same mugen system
07-19-2003, 10:26 PM
#17
New User
Join Date: Jul 2001
Location: city of angels, CA, USA
Posts: 6,380
Likes: 0
Received 0 Likes
on
0 Posts
Re: (1hotintegra)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1hotintegra »</TD></TR><TR><TD CLASS="quote">im done with the head... im doin the exhaust now so a 2.5 to a 2.36 wont be bad</TD></TR></TABLE> thats what i have and i put down 178 to the wheels...yes ideally a 2.5 to 2.5 would be best but it will still flow w/ a bottleneck.
07-20-2003, 12:14 AM
#18
Honda-Tech Member
Join Date: Nov 2002
Location: Chicago, IL
Posts: 4,691
Likes: 0
Received 0 Likes
on
0 Posts
Re: (1hotintegra)
i just got a greddy SS and installed it earlier today and i love it, i wouldnt think you need the jdm 4-1 header unless you had at least a 2.5" catback or a hi-flow cat to go with it.
i wrote up a little thing on my install:
https://honda-tech.com/zerothread?id=568086
got it for 272 shipped
i wrote up a little thing on my install:
https://honda-tech.com/zerothread?id=568086
got it for 272 shipped
Thread
Thread Starter
Forum
Replies
Last Post