| Weistec Horsepower | 420 |
| Weistec Torque | 339 |
| Manufacturer | Weistec |
| Street legal in all the US States | No |
| Stock Horsepower | 400 |
| Stock Torque | 325 |
| See more | |
| year | make | model | trim | engine |
|---|---|---|---|---|
| 2015 | Porsche | 911 Carrera 4S | (991.1) 7AT PDK | 3.8L Boxer 6 (MA1.03) |
| 2014 | Porsche | 911 Carrera 4S | (991.1) 7AT PDK | 3.8L Boxer 6 (MA1.03) |
| 2013 | Porsche | 911 Carrera 4S | (991.1) 7AT PDK | 3.8L Boxer 6 (MA1.03) |
| 2012 | Porsche | 911 Carrera 4S | (991.1) 7AT PDK | 3.8L Boxer 6 (MA1.03) |
| 2011 | Porsche | 911 Carrera 4S | (991.1) 7AT PDK | 3.8L Boxer 6 (MA1.03) |
| 2015 | Porsche | 911 Carrera 4S | (991.1) 7MT | 3.8L Boxer 6 (MA1.03) |
| See more | ||||
Product Description
The 991.1 Carrera S's 3.8-liter flat-six is one of the great redemption stories in Porsche engineering. Its direct-injection MA1 architecture finally put the intermediate-shaft and oil-starvation gremlins of the old M96/M97 sixes to bed for good with a proper wet-sump design, and the result is an engine that revs eagerly to 7,400 rpm for a full 400 factory horsepower. This is naturally aspirated 911 engineering at its absolute peak, the culmination of everything Porsche learned building high-strung flat-sixes, and it earned every bit of the reverence 911 purists still hold for it as the final naturally aspirated Carrera S engine.
Weistec's ECU tune for this engine is a software recalibration only. It refines the factory's own fuel, ignition, and throttle mapping with the same validation rigor as an OEM calibration, building directly on what Porsche already got right while leaving knock protection, thermal management, and every factory diagnostic fully intact. On the dyno, that work is worth roughly 20 hp and 14 lb-ft over stock, and it wakes up even more of this engine's high-rpm character. An already special engine, taken somewhere the factory calibration left on the table.
How Do You Get Your Porsche 911 Carrera S (991.1) ECU Tune Tuned?
Follow these steps — this is what your specific vehicle needs and supports.
Choose Your Tune Stage
Core Improvements
Standard with this tuneFree Add Ons
Pick Your Tuning Method

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

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

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.

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


