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Unlike many other performance vehicles, the Type R doesn’t offer a factory launch control system. In it’s place the car offers a stationary rev limiter of 3500rpm. This can help to regulate engine speed making a basic launch possible, however it uses the throttle to control RPM, leading to a low maount of airflow and little to no boost pressure. The lack of boost pressure and thus available torque from the engine can lead to a sluggish start.
COBB Custom Launch Control for Honda Civic Type R is a comprehensive system allowing multiple benefits. The first feature is a multi-part system that includes dynamic engine speed limiting and load targeting, allowing you to regulate and optimize wheel slip for a better launch. The system can even remain active through multiple gears in order to prevent excess wheel spin in traction limited vehicle speeds. The second function is a limiter that uses ignition and/or fuel cut instead of a throttle closure to build and maintain a target boost level allowing you to have a more aggressive launch with more power immediately available.
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Since users are able to adjust the load target with no regard for what is set as the target, it’s important to set the Launch Control Scaled Max to establish a hard limit for load after any adjustments from the AP. This will prevent the load from exceeding a safe limit in the event that an end-user adjusts this to more than what the engine would be able to hold.
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Interaction with Stock Rev Limiter Functions:
Several factory tables relating to rev limit hysteresis, integral and proportional gains for predictive torque reductions in engine speed limiting, and wastegate control have been modified in addition to our custom code. These tables have been modified to manage the response time and duration of fuel- and ignition-based torque reductions, maximizing boost response while stationary and in-gear.
Rev Limiter Response
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A new table group has been added under “Rev Rev Limiter Tables” Tables called “Rev Rev Limiter Response”Response. These tables are always active, not just when launch control is active. However, these These new tables are key for optimizing 1) a few different things. Firstly they can assist with boost response when stationary and preparing to launch, and 2) secondly the reactivity and “stickiness” of torque reductions made when encountering the dynamic rev limit as the vehicle accelerates in launch control.
To prevent engine overspeed, the factory control strategy calculates a predicted engine speed, compares that to actual engine speed and the current engine speed limiter, and can activate pre-emptive utilize torque reductions to avoid overshooting the rev limit. The following tables contribute to this system:· This is done via
Ignition Cut RPM Offset
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Predictive Rev Limiter Offset
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Rev Limiter Offset (Fuel Cut)
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Rev Limiter Offset (Fuel Cut)
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#2
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I-Term Gain RPM Control
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P-Term Gain RPM Control
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Time Delta Engine Speed Check
Modification of these tables can increase or decrease the threshold between actual RPM/and predicted RPM and as well as the rev limit where torque reductions can occur. The I-Term and P-Term tables specifically will contribute to how “sticky” these torque reductions are the engine reacts in terms of maintaining rpm by modifying how torque is ramped back in after encountering the rev limiter. We found that to optimize stationary boost response, strengthening these I- and P-Term effects while in gear zero (neutral) works best. However, to prevent sluggish acceleration when in gear, weakening these effects (numerically increasing their values) helped to bring return to the desired torque (via spark) back in faster after encountering after the reduction more quickly after instances of reduction due to the dynamic rev limit. Further tuning with these tables to fine tune traction and torque delivery may be necessary to optimize acceleration and quell wheel hop off the line.
Wastegate Control
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The tables “Wastegate Wastegate Special Position – Engine Speed Threshold” Threshold and “Wastegate Wastegate Special Position – Exh. Mass Flow (Fuel Cut)” were modified in OTS to ensure that the wastegate stays shut while on the stationary rev limiter, . By keeping the wastegate shut it has the effect of increasing boost immediately available off the line. If attempting to launch at an engine speed above 5000RPM, increase the Engine Speed Threshold table value. Similarly, if attempting to launch with significantly more boost pressure than what OTS creates (4-6psi), increasing the Exh. Mass Flow (Fuel Cut) table may be necessary.
VTC Control
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Although this table was not modified in OTS, we added a table to the VTC Tables group called “MaxMax. Engine Speed (Spool)”. This is a limiter on the maximum engine speed allowed when the variable cams are in Spool mode. Increasing this value to allow the variable cams to command significant overlap greatly benefits the amount of boost that can be generated while stationary – in testing, we were able to build up to 15psi with this limiter increased. VCT Spool mode triggering conditions are not fully understood at this time, but appear to use a delta between Air Charge and Air Charge Desired – when the difference is large enough, and engine speed is below this RPM limit, the cams are commanded into the relative positions calibrated in the Int./Exh. Camshaft Desired Angle (Spool) tables. Note that in the LC Load Target table that load target values at all engine speeds and zero MPH rear wheel speed, load target is set to 190.
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Additional Launch Control Limiters/Control
Launching the car properly isn’t just about making power at the line and sending it. It also involves staying in control of the car and optimizing traction. To that end we added a few other limits when under launch control.
Wheel Speed Max/Min
During the use of launch control, reducing power etc. based on wheelspeed can be very helpful as it acts a bit like traction control. However equally important is when you exit launch control and unleash the full power of the engine. As such, timing when the car exits launch control via your Wheel Speed Max can help make sure that once your car has started on it’s way, you are no longer reducing available power. In this way after the car gets up to a speed where traction is no longer an issue you can safely increase power.
Launch Control Load Scaled Max
This puts a cap on the amount of load the car is allowed to target when under boost control. That way when making adjustments at the track via the Accessports adjustments menu, you can make sure you don’t actually go a little too spicy.
Clutch Brake Bypass Switch
In the event that for a mechanical reason you aren’t able to use the factory clutch pedal to engage launch control, it will bypass the check that looks at the clutch pedal before activating launch control. Keep in mind that this means whenever the other factors (safety tables, wheel speed etc.) are within the proper range for the system to activate launch control, it will activate.
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Safety Tables
A few tables are built in to limit the use of launch control to situations where it is safe for the vehicle and user. These can be custom tuned or also disabled in the Launch Control Safety Switches folder if you like to live dangerously.
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