What header should I buy for my integ....what's the difference in hp? Should I try to install it myself or would it be better if I had it done at the place where I buy it at?

 

DC 4-1 Header!! 4-1 is much better. more power, and better acceleration. With a 4-1 header, you'll feel your car pull hard after 4000 rpm.

Try http://www.inlinefour.com

They should have sales...

 

DC 4-1

 

WHAT's THE BEST HEADER FOR A GSR or ITR?

the answer to what is the best header depends on where you want to end up with your GSR or ITR when all the mods are done (sorry for the long read). My apologies to LS owners, as this relates to VTEC tegs and I'll talk about the best choice for LS owners in a separate segment. ITR owners please go to number 2. Moderate Engine Upgrades and begin reading there. :

1. All Motor Bolt-ons Only

an example of this engine combination would be i/h/e, cam gears, FPR, underpulleys, skunk2 intake manifold, ECU reprogram or VTEC controller/Fuel controller, , stock 2 stage intake manifold, stock compression, and stock cams (around 155-175 whp).

DC Sports USDM, 1 piece, 4-2-1

In the bolt-ons only engines, the USDM DC 4-2-1 (not the USDM DC 4-1) header (both with the smaller 2 1/4 in. collector) is the better choice. BTW for you DC Sports nay-sayers, the Comptech, Airmass, and Greddy headers lost to the DC Sports in SCC mag's Oct 99 great header shootout in a bolt-ons only GSR (AEM CAI and Greddy exhaust).

If you plan on running nitrous, then the better material would be stainless steel over ceramic coated mild steel. Stainless steel (SS)is stronger and dissipates heat faster but unlike the myth about finishes, the stainless surface turns gold then grey, needing some elbow grease to polish them up. The flange is not made of SS and will rust over time. The ceramic coating on mild steel headers actually lasts better and runs the header cooler under the hood. Please avoid using header wrap on uncoated SS headers, as the inside of the header becomes a heat sink causing premature cracking.

For 1994-1999 GSR owners wanting to try an ITR header: the USDM ITR header is 2 in. too long on the GSR and you will need a shorter length cat. The ITR header will fit on an LS and 2000-2001 GSR.

2. Moderate All Motor Upgrade

Eg. of moderate engine combination upgrade package:

ITR,Crower 63402, Skunk2, or Spoon cams and upgraded valvesprings, bigger injectors,VTEC-fuel controller, thinner mugen gasket for 10.3-10.4-1 compression , plus or minus ported head, plus most listed in 1. (around 185-190 whp):

With Moderate Upgrades, the JDM ITR 4-1 header with 2 1/2 in. collector is better {performance and pricewise}. This header needs a custom 2 1/2 in. cat to make everything flow right and fit. The stock cat will NOT hookup and you will need to weld on an oxygen sensor bung to the cat (see section 5. below) . Please stay away from the Random Tech cat (with many reports of lack of quality control issues (bricks rattle around in 6 mo.), lack of fitment, and lack of hardware issues).

JDM ITR 4-1

Nasty!! FYI: This header is a copy of the Mugen 4-1 that is $450 more expensive...it's just not made of stainless steel with the finish of a Mugen and the Mugen diameter is slightly bigger in the primaries (45mm diameter in Mugen vs. 43mm in JDM 4-1) and secondaries (see the next post). It makes very close to the same power and you can get HPC Hypercoat,Airborn, Jet-Hot, Microcoat to coat it for you if the finish is a big deal to you. Don't forget to port out the header ports slightly for anti-reversion and the collector slightly to get more flow. If you are coating it, port the mentioned areas and weld the flanges before sending it off for coating.



http://hybrid.honda-perf.org/tech/jdmhdr/index.html
http://hybrid.honda-perf.org/tech/jdm41/

Mugen 4-1 (long primaries) with with the a bigger 2.5 in. outer diameter collector not USDM 2.25 in. OD collector.



The alternatives worth considering are:

a) DC Sports JDM 4-1 with 2.5 in. collector
http://inlinefour.com/dcsporjdm41h.html

The DC JDM is a price competition for the JDM ITR 4-1 and more readily available. We'll see how it affects the cost of the OEM JDM ITR 4-1.

b) the SMSP stepped adjustable 4-2-1

The SMSP has been shown to make 5-8 whp more than a ported JDM ITR 4-1. It is priced competitively in this niche.

If you don't want to do all this hassle of cat fitting and welding an O2 sensor bung, the next best is the USDM DC Sports 4-1 with 2 1/4 in. collector which hooks up at all the stock mounting points.


3. Extreme All Motor Engine Combination: The All Motor Mantra

Eg. of this engine combination:

64-68 mm overbore TB or individual TB's (Blitz, Toda, TWM), Toda cams (Spec A, B,or C) or Jun type 3 cams ,or Crower 63403 cams, single stage intake manifold (Skunk2), 11:1 or more compression from pistons (with rods upgraded), ported head, 9000-10,000+ rpm redline and VTEC 6300-7500 rpm from ECU reprogram. (>195 whp)

the best header here are the ones with bigger diameter, longer primaries and with the a bigger 2.5 in. outer diameter header collector. What separates them? diameters, steps, antireversion chambers, primaries and secondaries length, fitment, steepness of collector angles, materials/finish, and customer support :

Examples include the Hy Tech hybrid 4-2-1 used by L'Natural and Skunk2, SMSP adjustable headers, Spoon long primaries 4-2-1 , and Toda long primaries 4-2-1 .

Hy Tech CARB legal, stepped, long primaries hybrid 4-2-1 with antireversion chambers (stainless steel): sequential pairing, long secondary merge



SMSP adjustable, stepped, long primaries 4-2-1 (coated mild steel): sequential pairing, long secondary merge



Spoon stepped long primaries hybrid 4-2-1 (stainless steel): sequential pairing, short secondary merge



Toda stepped long primaries 4-2-1 (stainless steel): 1-4, 2-3 pairing, long secondary merge



4. Jackson Racing or Vortech Supercharger

best header here with forced induction is either the Kamikaze short primaries 4-1 with 2.5 in. collector or the Hi Tech SC 4-1 short primaries superheader with 3 in. collector. The shorter length helps evacuate the huge exhaust volume out.

Kamikaze short primaries 4-1



Hy Tech stepped short primaries 4-1 SC header




Please get the SC first then the header, cat., and 3 in. exhaust to support it.

5. Links to 2.5 in. to 3 in. OD Aftermarket Cats

please check out the tech archive in the integra forum under Carsound Cat.

Car-Sound Universal Cats 94000-95000 series

Magnaflow

Let me get you in on something: Magnaflow and Car-Sound are the same manufacturers for cats.

Adrian Teo Custom Cats

Jegs/Dynamax

6. Examples of not thinking ahead and making a mistake of buying the wrong header for the wrong combination: you now have to buy a 2nd header.

a)

if you got a USDM DC Sports 4-2-1 with Toda Spec B cams, the cam's big air :fuel delivery and big amounts of burnt gases will be choked by the small collector and primaries diameter.The cam's gains will be stiffled in the upper rpms by that header which is very good but for the bolt-ons crowd only. Roger Foo used to run this header in his monster b16a that makes at least 190 whp from 1.6L all motor with it but remember, he ran an open header and has since switched to an SMSP.

b)

if you drop in a Mugen 4-1 with bigger diameter and bigger Japanese 2.5 in. collector or Spoon long primaries 4-2-1 with 2.5 in. collector to a bolt-ons only car, it will lean out the car big time and the flow is not adequate enough to need a bigger primaries diameter so the gas velocity leaving the head dies. This leads to a loss of power especially in the midrange. Even the Mugen 4-1 with compatible header collector to a smaller stock 2.25 in. US cat (in the Oct 99 Sport Compact Car Magazine great header test) lost 1-2 lb ft of midrange torque.

c)

if you got the smaller USDM DC Sports 4-2-1 header and then got the JRSC, the collector would choke off the SC extra burnt gases from escaping compared to the kamikaze 4-1. The Mugen 4-1 long primaries or Spoon long primaries 4-2-1 were meant for all motor power and would be too long for the SC. Long primaries would blunt the gas exit velocity out of the head.


IF YOU REMEMBER JUST 1 THING FROM THIS THREAD: BUYING A PART? PLEASE THINK FIRST ABOUT WHAT ENGINE COMBINATION YOU WILL END UP REALISTICALLY RUNNING (BUDGETWISE IN 2-3 YR) AND HOW IT WORKS WITH THE OTHER PARTS...PLEASE MAKE SURE THE PARTS (INCLUDING A HEADER) ARE COMPATIBLE FOR THE FLOW NEEDED, RPM RANGE YOU ARE USING, COMPRESSION RATIO, ROD RATIO, AND DISPLACEMENT!
(superhonda.org/board) article.

 

Wow, Excellent input.

And How about for LS owners? and the differenace from Auto and if you manual?

Thanks again

 

Anyone?

 

excellent analysis dr. pineapple!

 

yes very good