2001 ITR #895 is a dyno queen. A test *****. When I purchased the car in July of 2003 it had the OEM JDM 4-1 header and a CAI. I threw some Skunk2 Stage 2 cams, RC 310 injectors, and Hondata in her (parts I had laying around) installed an AEBS IM and had Shawn Church tune the car. Around 200 peak whp and a nice mid range curve. But since I can never leave well enough alone, I got my hands on a used HyTech big tube header and went back for some tuning. The butt dyno was telling me that I was slower; I figured A/F tuning would help. The butt dyno was right-huge dip in the mid-range that could not be tuned out (cam gears and A/F). Peak was about 208, but peak numbers ain't everything Enter the third header a Comptech 4-2-1 race header. Back to the dyno. Recovered much of the mid-range and still had better peak numbers than the JDM 4-1. All of this is on a stock block ITR and a stock port head. The HyTech header is designed for a 2 liter engine, and it absolutely kicks *** on my 85mm GSR motor, but the little 1.8 just can't flow enough for the big tubes.
Here are the charts:
Black line = Comptech
Darker red line = JDM 4-1
Red line = HyTech 2 liter header




Cliff notes: Big (JDM 4-1), bigger(Comptech), biggest (HyTech big tube).
Biggest made the most peak.
Smallest had the best mid range.




Modified by b19coupe at 6:05 AM 4/1/2004

 

good stuff
just goes to show, all components must compliment one another


Modified by Dan GSR at 1:09 PM 4/1/2004

 

Im so tempted to try another header...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RTW DC2 &raquo;</TD></TR><TR><TD CLASS="quote">Im so tempted to try another header...</TD></TR></TABLE>

Try mine


&lt;--Desperately trying to save money for parts

 

LOL m4d t0rkz y0

 

Were all three headers fully tuned?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by itr 00 0108 &raquo;</TD></TR><TR><TD CLASS="quote">Were all three headers fully tuned?</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b19coupe &raquo;</TD></TR><TR><TD CLASS="quote">Hondata.... had Shawn Church tune the car</TD></TR></TABLE>

 

which Comptech header?

The Race, or the 4-2-1 ?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tweakmeister &raquo;</TD></TR><TR><TD CLASS="quote">which Comptech header?

The Race, or the 4-2-1 ?</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b19coupe &raquo;</TD></TR><TR><TD CLASS="quote">Enter the third header a Comptech 4-2-1 race header.</TD></TR></TABLE>

 

I saw that RJ, I asked if after every time a header was taken off and another put on, was it tuned all over again?

FULLY tuned.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by itr 00 0108 &raquo;</TD></TR><TR><TD CLASS="quote">I saw that RJ, I asked if after every time a header was taken off and another put on, was it tuned all over again?</TD></TR></TABLE>

Why wouldnt it be? Whats the point of testing otherwise?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">FULLY tuned.</TD></TR></TABLE>

Que?

 

comptech, y0

 

How much more power do you think you would have gotten if you added a ~2.5" exhaust. I assume you were running stock?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RJ &raquo;</TD></TR><TR><TD CLASS="quote">

Why wouldnt it be? Whats the point of testing otherwise?

Que?</TD></TR></TABLE>

Doesn't sound like you were there....let him answer.

 

thanks for the review , it shows that a header will flow as much as the motor will breath.
Im sure the hytech header is great for a 2.0l set up ...
while the JDM and the comptech more then enought for a 1.8 stock bored ..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GokuSSJ4 &raquo;</TD></TR><TR><TD CLASS="quote">thanks for the review , it shows that a header will flow as much as the motor will breath.
Im sure the hytech header is great for a 2.0l set up ...
while the JDM and the comptech more then enought for a 1.8 stock bored ..</TD></TR></TABLE>

While true, I dont know if that answer is what one should derive from this. Too many factors to consider.

This is the Hytech big tube which is set up for highly modded motors. I've seen the thing work wonders on a 1.8, it isn't necessarily the displacement

But I do see what you're saying

 

could you compare ground clearance of the three?

thanks!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tweakmeister &raquo;</TD></TR><TR><TD CLASS="quote">which Comptech header?

The Race, or the 4-2-1 ?</TD></TR></TABLE>

This one:



Each header was fully tuned air/fuel and cam gears with one exception; we did not play with the cam gears on the Comptech header.

 

which one did you actually end up keeping on the car?

 

correct me if Im wrong, but on Church's dynapack he removes your wheels when tuning your vehicle? Isnt there a 10 hp discrepancy between those on the dynapack and those on the dynojet? ID be curious to see what #s your car would have put down on a dynojet...nevertheless nice results, especially with a stock bottom end...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RTW DC2 &raquo;</TD></TR><TR><TD CLASS="quote">which one did you actually end up keeping on the car? </TD></TR></TABLE>

Tha last one I tested, the Comptech.


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18c-rDC2 &raquo;</TD></TR><TR><TD CLASS="quote">correct me if Im wrong, but on Church's dynapack he removes your wheels when tuning your vehicle? Isnt there a 10 hp discrepancy between those on the dynapack and those on the dynojet? ID be curious to see what #s your car would have put down on a dynojet...nevertheless nice results, especially with a stock bottom end...</TD></TR></TABLE>

You are correct. The car was at Rage Imports a couple of weeks ago for their dyno day with the Comptech header, untuned:

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dan GSR &raquo;</TD></TR><TR><TD CLASS="quote">good stuff
just goes to show, all components must compliment one another</TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Padawan &raquo;</TD></TR><TR><TD CLASS="quote">

</TD></TR></TABLE>

People are forever calling things "race" this, and "type r y0!" that. Wording is an exact science

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tweakmeister &raquo;</TD></TR><TR><TD CLASS="quote">

People are forever calling things "race" this, and "type r y0!" that. Wording is an exact science </TD></TR></TABLE>

Yes, and Comptech does not help matters by naming both style headers "4-2-1".

As an aside, just so people don't get the wrong impression about the HyTech header, here is a graph with no torque dip at 6,000 , on an engine that the header was designed for (85mm 13.6:1):


This dyno was done to test the VictorX IM against the ITR IM on this motor.
Green line = ITR IM.
red line =VictorX IM