Vtec controller
- Thread starter chrisvtec
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- Joined
- Jan 29, 2008
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What these do is allow you to tap into the appropriate lines on the ECU harness to the controller, it reads, and modifies the signal coming to and from the ECU, to and from the sensors. This is why it’s called a Piggy-Back computer. It can also allow you to take away percentages of fuel in 500 RPM increments. This should be done in conjunction with a fuel pressure regulator. Most ECU's tend to run rich...meaning too much fuel, too little air, which doesn’t produce the full amount of power that it can.
Before buying a fuel controller and leaning out the fuel, it is important to remember that too lean and you can cause detonation. So it’s not wise to just tune it on some back road. These controllers need a dyno and a professional tuner to play with the settings to see what effect it’s actually having on the fuel air ratio.
The air fuel controller tuning is just done to smooth out the power band and eliminate dips and spikes on your power curve, so that you can have a flat more linear torque and hp curve.
Onto the VTEC controller part.
VTEC engagement on a stock car is OPTIMIZED. If you play with it, all you are really doing is taking away power, despite what it "feels" like. However by bringing the VTEC crossover up or down around 500 or even 1000 rpm up or down may indeed improve your power curves. Again, this is something u can only prove if you are on a dyno and u can see the immediate results.
On a VTEC motor there is a VTEC cam lobe and non VTEC primary and amp secondary cam lobes. Those non VTEC lobes are optimized for low end power delivery. However, at upper RPM, the small lobes cannot deliver enough air or keep the valves open long enough to continue to let the motor make power. The VTEC cam lobe takes over duties in opening and closing the valves from the secondary and primary lobes. Since the VTEC cam lobe is much taller, it can now provide more air and duration the motor needs to keep making power at higher RPM. So what does setting VTEC at 3,000 rpm do? It makes a cam lobe designed to work well at high rpm to work at low rpm. Conversely, setting VTEC too high will cause the motor to start dying out, and then jump forward when the VTEC lobes take over.
The above is also a good way to determine a starting point for an optimal VTEC x-over when you have done some internal mods and u would like to set VTEC at a certain point. Take a dyno pull with VTEC set low, then another pull with VTEC set really high. Overlap the graphs and where the curves intersect where power falls off and where power comes up is where you should start to position crossover point.
Before buying a fuel controller and leaning out the fuel, it is important to remember that too lean and you can cause detonation. So it’s not wise to just tune it on some back road. These controllers need a dyno and a professional tuner to play with the settings to see what effect it’s actually having on the fuel air ratio.
The air fuel controller tuning is just done to smooth out the power band and eliminate dips and spikes on your power curve, so that you can have a flat more linear torque and hp curve.
Onto the VTEC controller part.
VTEC engagement on a stock car is OPTIMIZED. If you play with it, all you are really doing is taking away power, despite what it "feels" like. However by bringing the VTEC crossover up or down around 500 or even 1000 rpm up or down may indeed improve your power curves. Again, this is something u can only prove if you are on a dyno and u can see the immediate results.
On a VTEC motor there is a VTEC cam lobe and non VTEC primary and amp secondary cam lobes. Those non VTEC lobes are optimized for low end power delivery. However, at upper RPM, the small lobes cannot deliver enough air or keep the valves open long enough to continue to let the motor make power. The VTEC cam lobe takes over duties in opening and closing the valves from the secondary and primary lobes. Since the VTEC cam lobe is much taller, it can now provide more air and duration the motor needs to keep making power at higher RPM. So what does setting VTEC at 3,000 rpm do? It makes a cam lobe designed to work well at high rpm to work at low rpm. Conversely, setting VTEC too high will cause the motor to start dying out, and then jump forward when the VTEC lobes take over.
The above is also a good way to determine a starting point for an optimal VTEC x-over when you have done some internal mods and u would like to set VTEC at a certain point. Take a dyno pull with VTEC set low, then another pull with VTEC set really high. Overlap the graphs and where the curves intersect where power falls off and where power comes up is where you should start to position crossover point.
- Joined
- Jan 29, 2008
- Messages
- 6,259
No problems. Hope it helps