Just Did Some Quick Header Testing..........
The other night we decided to go ahead and do a little dyno comparison on a couple headers that we had laying around. The testing was done in a back to back fashion with tuning done to air/fuel and timing accordingly for each header. The runs selected below are both at the same temperatures, in the same style run conditions, within an hour of each other.
The chart below is of the TDM Hytech Big Tube Copy vs. the Spark Racing SMSP Copy.
The purple/fuschia line is the Spark header
The black line is the TDM Hytech Big Tube
The black line is the TDM Hytech Big Tube

The Spark Header peaked at 224whp and 144wtq
The TDM Header peaked at 228whp and 148wtq.
The TDM Header peaked at 228whp and 148wtq.
The Spark Racing header gave us some great midrange from 6000-7200 rpm's with as much as 20whp and 11wtq in some areas. Otherwise anywhere else on the rpm range was dominated by the Hyech Big Tube Copy. I'm sure that an actual real header from either real company would dominate either of these clones without question. These cheap alternatives do still show a little potential for the investment spent. I feel that the BigTube header might've sucked balls in the midrange due to the lack of displacement in our test engine and possibly because the way the runners are paired.
The specs on the engine used for testing are:
"b18c1 block with CTR pistons on gsr rods
All honda bearings,seals,pumps,and belts
pr3 head with portflow standard headwork
Full omnipower valvetrain set
Blox Type 3 cams with skunk2 cam gears
RSR gt2 exhaust
Buddy club headgasket
Reused over and over thermal intake gasket
PerformerX Intake Manifold
professional products 68mm throttle body
Custom ProFunction Tuned Length Intake w/ Vstack
Tuned on Crome pro"
All honda bearings,seals,pumps,and belts
pr3 head with portflow standard headwork
Full omnipower valvetrain set
Blox Type 3 cams with skunk2 cam gears
RSR gt2 exhaust
Buddy club headgasket
Reused over and over thermal intake gasket
PerformerX Intake Manifold
professional products 68mm throttle body
Custom ProFunction Tuned Length Intake w/ Vstack
Tuned on Crome pro"
For reference numbers on how nutty this little pump gas budget engine is, here is a dyno layover of our best run vs. a recently tuned K20-R w/ RBC mani, Custom Cold air w/vstack, Rcrew header, and BC Spec2 exhaust on Kpro.
Black Line= K20R
Purple Line= 1.8L Vtec Budget Engine

Purple Line= 1.8L Vtec Budget Engine

Obviously we couldnt do anything against the mightyness of displacement or the excellent powerband found from VTC, but going by the numbers it's a stronger engine from 7200RPM all the way on.
The K20R peaks at 218.5whp and 157.2wtq
The B18C peaks at 229.4whp and 149.7wtq
The B18C peaks at 229.4whp and 149.7wtq
We look to do more comparisons in the near future, stay tuned! ;)