Finally made it down to Street Flight dyno yesterday, even though I was having some car issues.

This is a JDM ITR header with the inner welds smoothed (dremeled) and rewelded on the outside. Also using a 2.5" test pipe.
I measured the collector size on each header.
The JDM ITR has a 2 3/8" collector while the USDM DC 4-1 has a 1 7/8" collector.

Final results were a maximum of 166.2 WHP and 140.6 TQ.
Thats a gain of 6 WHP and a loss of 1/2 FT-LB of TQ.
As can be seen...some midrange power was lost...on average around 1-2 HP and 2-3 TQ betwwen 4000 and 5300.



I was pretty surprised with the gains especially considering I already had a 4-1 aftermarket header before.





[Modified by HX_Guy, 8:43 AM 9/4/2001]

 

I almost choked when I saw 140 in torque ... then I read your sig.

I thought you had a stock ITR motor wiht 140 torque.


Greg

 

Nice! Just wondering, are you going to do the same with the JDM DC 4-1?

 

You mean dyno test a JDM DC 4-1? I wish I could...would a shop like to donate one?