The biggest gift Honda has given to tuners of the K series engine is the VTC mechanism. Located on the end of the intake camshaft the VTC mechanism, via hydraulics allows 25 [crank] degrees of continuous movement on the TSX and 50 degrees on the RSX. For all you old school tuners lurking out there still changing the jets on your carburetors, who think you have to junk the VTC mechanism and go with a good old fashioned cam timing wheel, think again. In every naturally aspirated engine K20a and K24 engine we have tuned, the intake cam needs to be rotated through 25-30 degrees between peak torque and peak power. For emissions, the ability for Honda to rotate the cam to zero at idle to dial out all overlap makes for a very clean engine with no need for EGR. EGR porting is on place on the head but is blocked off.

25 degrees of cam movement is fine for a stock TSX engine but completely inadequate for modified engine with as little as race headers and intake. A stock engine needs no more than 20 degrees of cam moment on the high cam. A well modified setup needs no less than 25 degrees on the high cam. Take a good look at the modifications we made to the VTC mechanism. If you have a TSX you are going to need these changes. Although you could probably purchase and bolt on an RSX VTC mechanism for 50 degrees travel, there is less valve to piston clearance on the TSX pistons. Our measurements suggest 45 degrees maximum cam movement is much safer. Allowing the full 50 degrees movement leads to a greater risk of valve to piston contact should you accidentally mis-shift and over-rev.

the map that was posted used stock TSX basemap, in some area's it wants 30VTC where the machanical limits of the TSX VTC varies 1-2degree's i've seen the actuall TSX cam, go to 28degree on one datalog mostly would stick around 27 degree, your asking about stuff in 2004 I have the old dynochart from 2004, but the motor was new, and the TSX map didn't exist then. a different header was also used. so it's safe to assume pull away a couple hp, where the 30degree angles are, from the additional difference from the documented27 degree to 30 and it's pretty accurate, If you guys really wanted to know I could have locked it at 27 degree's instead of 30. But i wanted to show you guys the difference... so actually if you think about it... the TSX map, would have still been better than stock, because the stock VTC would have locked it sooner, so the results in difference would be greater. for the added 2-3 degrees only on the low cam.

The primary oxygen sensor from the 02-04 RSX or 02-05 Civic Si part number 36531-PRB-A01 must be used. The 03-06 Element O2 sensor will not work.
OBD2 must be disabled to eliminate errors generated by the ECU looking for emissions items that the 03-06 Element does not have.
The speed sensor spins about 100 times faster on the Element MT gearbox as compared to the 02-04 RSX. Above 65-70 MPH cruise control may not function smoothly and may cancel from time to time. Also see Tech - K20 Transmissions
Hondata makes hardware modifications to a donor 2002-2004 K series ECU (see below) to enable it to work with the different sensors and actuators found on the 2003-2006 Element. After these modifications the ECU will not function correctly on a 2002-2004 RSX.