Fields Vtec Controller ?
ok i got a 96 hb with a GSR motor. Just recently installed the vtec controller only for using the vtec adjustments. I didnt hook up the map sensor wire to the map.. Qustion is why are the Rpms and the Speed on the Controller so far off from the ones on the cluster??
thanks
thanks
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JdmGlenn »</TD></TR><TR><TD CLASS="quote">just changing vtec engagement. It seems like EVERYTHING on the Fields is off </TD></TR></TABLE>
Let me post this one more time:
VAFCs or any other type of VTEC controller. They simply provide +12v to the VTEC solenoid at whatever RPM is specified. Some of you may think this is great. BUT (There's always a but isn't there) the VTEC controller does not communicate with the ECU in any way, shape, or form. The ECU has two separate sets of maps that it uses for VTEC applications. A low cam set when VTEC is not active and a high cam set when VTEC is activated. When ECU engages, the ECU switches maps to provide the engine with the correct ignition curves and fuelin for the higher cam lobes. Even though you can specify when the VTEC engages with a VTEC controller the ECU still switches maps at it's stock programmed point. If you set VTEC lower than stock you are in high cam while still running on the low cam maps until the ECU's programmed point. If you set VTEC higher than stock you're in high cam maps while you're still in low cam from the ECU's stock point until the VTEC controller's set point. Adjusting the VTEC point with a VAFC can cause a lean or rich condition and force you to use the VAFC to adjust fuel during the tuning process, which would adjust your ignition timing (as mentioned above) even more. Now, not only are you not in the correct maps, but the VAFC is changing the MAP sensor voltage and your ignition curve is going all over the place.
Let me post this one more time:
VAFCs or any other type of VTEC controller. They simply provide +12v to the VTEC solenoid at whatever RPM is specified. Some of you may think this is great. BUT (There's always a but isn't there) the VTEC controller does not communicate with the ECU in any way, shape, or form. The ECU has two separate sets of maps that it uses for VTEC applications. A low cam set when VTEC is not active and a high cam set when VTEC is activated. When ECU engages, the ECU switches maps to provide the engine with the correct ignition curves and fuelin for the higher cam lobes. Even though you can specify when the VTEC engages with a VTEC controller the ECU still switches maps at it's stock programmed point. If you set VTEC lower than stock you are in high cam while still running on the low cam maps until the ECU's programmed point. If you set VTEC higher than stock you're in high cam maps while you're still in low cam from the ECU's stock point until the VTEC controller's set point. Adjusting the VTEC point with a VAFC can cause a lean or rich condition and force you to use the VAFC to adjust fuel during the tuning process, which would adjust your ignition timing (as mentioned above) even more. Now, not only are you not in the correct maps, but the VAFC is changing the MAP sensor voltage and your ignition curve is going all over the place.
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