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ENGINEERING THE FUTURE OF PERFORMANCE ™
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MP4 12C ECU Tune
Purchase MP4 12C ECU Tune
  • SKU: 05-838-00081-3

    MP4 12C ECU Tune

  • Advertised gains are estimates of HP and Torque “at the engine” calculated from gains as measured on a Dynojet Dynamometer in ideal conditions and typically show the largest possible change.  Actual gains are dependent on the following: Learn More about Crank HP Vs Wheel HP

    Model – Manufacturers use the same engine in multiple model vehicles and often times they are in a different state of tune, for example: 2008 C63 and a 2008 CLK Black Series.  Both have the same engine, but the C63 has 451hp while the CLK63 has 500hp.  Naturally the C63 will show more gains as it starts at a lower level.

    Model Year – Similar to above, as time progresses, Manufacturers tend to slightly increase power output via software from one year to the next or offer “Performance Packages” with increased power.  The engines remain largely unaltered and as a result, final tuned output remains the same, while the gains are lower as the starting point is now higher.

    Fuel – Fuel quality is HIGHLY important with performance vehicles.  Low quality and/or low octane fuel will greatly impact engine output and potentially even engine health.  Top tier brand premium fuels should always be used to achieve the best results possible.

    Drivetrain – All wheel drive has higher drivetrain losses than rear wheel drive.  This results in lower numbers when testing on a chassis dyno.  Wheel/tire size and weight will also impact chassis dyno results

    Weather/Conditions – Temperature, humidity, altitude, and air density all impact engine performance.  Heat, high humidity, and thin air will all work towards reducing engine output

    Engine Health – Higher miles tends to result in increased build up and lower compression which can and will impact engine output.  Properly maintained engines will have better performance than abused or neglected engines.

    Supporting modifications – The highest power levels require supporting modifications.  Depending on the engine, this could mean forged internals, built transmission, upgraded fuel system, 110+ octane race fuel, etc.

  • Stage:
  • $2,999.00 $2,999.00

  • Prop 65 warning
    Warning

    This product can expose you to chemicals including carbon black, silica - crystalline, formaldehyde, and lead which are known to the State of California to cause cancer, and lead, which is known to the State of California to cause birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.

Weistec Horsepower 730
Weistec Torque 652
Manufacturer Weistec
Street legal in all the US States No
Engine Family M838T
Stock Horsepower 625
See more
year make model trim engine
2014 McLaren MP4-12C Spider Twin Turbo 3.8L V8 (M838T)
2014 McLaren MP4-12C Base Twin Turbo 3.8L V8 (M838T)
2013 McLaren MP4-12C Spider Twin Turbo 3.8L V8 (M838T)
2013 McLaren MP4-12C Base Twin Turbo 3.8L V8 (M838T)
2012 McLaren MP4-12C Base Twin Turbo 3.8L V8 (M838T)

Product Description



The MP4-12C is the car that brought McLaren back. It was the first all-new production McLaren built since the legendary F1 left showrooms, and the first car ever to wear the newly formed McLaren Automotive badge, which is a huge amount of history riding on one engine bay. That engine, the 3.8-liter M838T, is a genuinely special piece of engineering: a 90-degree, flat-plane-crank twin-turbo V8 developed with the UK's Ricardo, whose cylinder bore can be traced all the way back to a Nissan-derived block that TWR originally built for an IndyCar program that never even got to race. McLaren clearly believed in what they'd built, because they didn't sit still with it, bumping factory output from 592 PS to 625 PS and wrapping it all in the carbon-fiber MonoCell chassis that became the template every McLaren since has been built around.

Weistec's ECU calibration takes that already remarkable M838T and pushes it further, working entirely within the engine's own software architecture rather than bolting anything on top of it. Every factory protection McLaren engineered in, from knock detection to thermal management to OEM diagnostics, stays fully active and untouched. It's an OEM-level recalibration, built with the same rigor as a factory engineering program, and on the MP4-12C that means real numbers: a jump from 625 hp and 443 lb-ft to 730 hp and 652 lb-ft. This was the car that put McLaren back on the map. With Weistec's calibration behind it, it's operating on a whole different level.

How Do You Get Your MP4 12C ECU Tune Tuned?

Follow these steps — this is what your specific vehicle needs and supports.

2

Choose Your Tune Stage

3

Core Improvements

Standard with this tune
  • Increased Horsepower
  • Increased Torque
  • Improved Throttle Response
  • Optimized Fuel and Spark
  • Increased Boost
  • Top Speed Limiter Removed
4

Free Add Ons

Want it louder?

Read more about Burble & Pops →

This tune can have Burble/Pops added or increased on deceleration, at no additional charge. Select an intensity below and we'll add it to your order, or mention it when requesting your tune — through the Cypher+ app, your calibration request form, or when placing your order.

Want to stop the stopping?

Read more about Auto Start-Stop →

Auto Start-Stop can be turned off as part of your ECU tune alone, at no additional charge. Just mention it when requesting your tune — through the Cypher+ app, your calibration request form, or when placing your order.

5

Pick Your Tuning Method

See the full tuning process →
1Selected

Cypher Plus

Order a Cypher Plus and tune your car yourself from your phone, entirely through the MyFlasher app. Watch how it works.

2Selected — Pick return shipping at checkout

Mail It In

Remove your ECU or TCU and mail it to us for tuning. Required for some applications.

3Selected — Pick Will call at checkout

In Person

Bring your vehicle, or just your ECU/TCU, to our Anaheim, CA headquarters. Call 714-202-0005 or email sales@weistec.com to schedule.

4Selected — Order through your local dealer

Cypher Pro Dealer

Visit a certified Cypher Pro Dealer near you. Find one with our dealer locator.

6

Complete The Upgrade

An ECU tune alone won't remove all factory limits or fix how power reaches the ground. Add these to round out the upgrade with no limitations.
Read the full CPC & TCU breakdown →

What is a CPC module?

The CPC (Central Powertrain Control) is a separate control unit that manages things like the active exhaust valves, radiator fan, intercooler pumps, and speed limiter. On many newer Mercedes-Benz vehicles, it also houses torque limiters that can hold back an ECU tune from reaching its full potential.

What is a TCU tune?

A TCU (transmission control unit) tune delivers faster, firmer shifts with higher line pressure, reducing clutch slip and increasing the transmission's torque capacity. It's a worthwhile upgrade on its own, or paired with an ECU tune for a fully sorted powertrain.

Your Total  

Good to Know

  • This is a reflash of your original module, not a stand-alone unit.
  • Power gains vary by vehicle, modifications, fuel, and operating conditions (ambient temperature, altitude, etc.).
  • New or upgraded spark plugs are always recommended when tuning.
  • Product may not be emissions compliant. Check local laws prior to installation.
  • Always use a battery charger during programming.