The Comptech header used during the great header test was the carb legal 2.25'' one right? Was that bolted up to the stock cat and b-pipe?

Just wondering since the rest of the headers seem to be 2.5'' yet the comptech makes just as much power.

 

Actually the Comptech street header has a 2" collector. And yes its carb legal.

This is what Comtech said when I asked exactly what size their collector was on the street header:
"The collector pipe itself is 2-1/4" but it does step down a bit to 2.14" at the flange. This is needed so that the correct gasket can be used. The effect on power is negligible."

The only cat used in The Great Header test was a 2-1/4" Carsound used with the oem ITR header and cat back.
The Comptech header used a 2-1/4"x 2-1/2" stepped test pipe with a 2-1/2" cat back
The other JDM headers used a 2-1/2" test pipe.


Modified by BlueTeg at 6:20 PM 7/1/2003

 

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BlueTeg &raquo;</TD></TR><TR><TD CLASS="quote">"The collector pipe itself is 2-1/4" but it does step down a bit to 2.14" at the flange. This is needed so that the correct gasket can be used. The effect on power is negligible."</TD></TR></TABLE>

Thanks.
Its hard to believe it makes are much power as it does with that bottleneck in it.

 

183 at the wheels baby with the Comptech 4-2-1 and a 2.5" exhaust and high flow cat. Stock intake.

 

amazing power considering the size....

 

the comptech is what i run, with a test pipe of course

 

.................

 

I wonder how that header would fair with a 2.25 or 2-3/8 exhaust piping on it? I'm sure the 2.5" helped it out quite a bit.

 

On a bone stock R like the one tested, a Comptech street header + a 2 3/8" header back exhaust would most likely perform pretty close. At about 165 whp (stock output of the itr) you really don't need 2.5" piping. The 2.5" begins to show advantages when you start increasing the power into the mid-170's and higher.