More Power for the APD Acura TSX K24 A2 Engine!


More Power for the APD Acura TSX K20 A2 Engine!
Under the valve cover is the somewhat complicated i-VTEC cam control system.  i-VTEC controls the intake cam phasing plus it has two sets of cam lobes, a high RPM cam lobe and a low RPM cam lobe.


The APD Acura was transported by Emergency Hookers to Robert Green and Ben Tran at Blueprint Racing in Walnut, Ca for installation of a set of BP Racing Stage 2 Cams and a modified Acura RSX VTEC actuator mechanism. (Blueprint modifies a stock Acura RSX-S Actuator to mechanically limit advance to 35 degrees from factory stock 50 Degrees in the K20, RSX. In the K24A2 Honda Engine with stock height pistons, 35 degrees is about the limit of advance to safely ensure valve to piston clearance in the event of  an over rev condition).

More Power for the APD Acura TSX K20 A2 Engine!
The cam advance/retard mechanism is on the intake cam.  It has been modified for less control authority.


04 TSX cams/BP Stage 2 cams – The math differences, Lift/Duration/Lobe Size:

04 TSX BP Stage 2
Max Lift 11.45mmMax Lift 12.6mm 
Duration 210 @ .050Duration 295 @ .050
Max Lift 11.50mmMax Lift 11.8mm
Duration 212 @ .050Duration 285 @ .050


04 TSX/BP Stage 2 Lobe Measurements:

Intake  Non-VTEC

Intake  VTEC

Exhaust   Non-VTEC

Exhaust  VTEC

04 TSX  Lobe Measurements:

Intake  Non-VTEC

Intake VTECExhaust   Non-VTECExhaust VTEC


More Power for the APD Acura TSX K20 A2 Engine!
Here you can see the high RPM lobe, the twin low RPM lobes and the screw type lash adjusters.  At least it’s easy to set the valve lash on this engine!


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