1.0 Background
1.1 Summary
This test project is being undertaken in collaboration with Stratified Automotive Controls and Shuenk to investigate optimizing EA888 (Gen 3) engine torque production. The experiment will involve use of an IS38+ turbocharger, mixed ethanol and gasoline fuels, and manipulation of data values within the Mk7 GTI engine management computer.
Stratified Automotive Controls provides calibration work as well as engine tuning and optimization expertise.
Shuenk supplies aftermarket turbochargers built with increased robustness compared with the OEM IS20/IS38 turbochargers.
1.2 Previous Test Results
Engine performance of this GTI utilizing an EQT custom ECU tune on 93 octane gasoline with stock fueling parts and a Shuenk IS38+ turbocharger was documented during a dyno session.
2.0 Purpose of Test
- Record IS38+ CHRA rotation speed.
- Optimize engine torque production within hardware limitation.
3.0 Systems Under Test
3.1 Automobile
A 2015 Mk7 GTI SE is the vehicle that will be used during testing. The GTI is equipped with a “built” EA888 (Gen 3) engine. A change from the OEM delivered engine affecting testing is an HPA High Pressure Fuel Pump (HPFP).
A complete listing of vehicle modifications is summarized here.
3.2 Turbocharger
Shuenk “IS38+” turbocharger. Similar in size to the OEM IHI IS38 turbocharger found in the Golf R.
3.3 Engine Management Software
Stratified Automotive Controls will utilize the Cobb Accessport to change data values of the Simos18 engine management computer.
3.4 Test Instrumentation
Measurement systems that will be used during testing consist of:
- Cobb AP – Sampling rate of ECU reported data at 30-40 Hz.
- DataQ – Adjustable sampling (1-240 Hz) of 8 channels.
- Temperature probes – RTD style air temperature.
- Pressure sensors – Absolute and differential.
- Fuel-It – Ethanol content analyzer.
- Garrett – Turbocharger Speed Sensor.
- Dragy – Vehicle position at 10 Hz.
4.0 Scope of Test
4.1 Test Environment
Testing will be conducted in Florida. Drag strip will be the preferred location and roadways will be secondary.
4.2 Test and Test Conditions
The primary test point is a full throttle acceleration in third gear beginning at 2,500 RPM and continuing to 6,500 RPM.
Testing at the drag strip should allow for continuation from third gear into fourth gear.
Because the test objective is gathering data, repeatability of the data collection methods is prioritized. Drag strip reported elapsed time and trap speed will be useful for relative performance assessment, but not useful for comparison with other vehicles. For example, the requirement to begin the third gear acceleration below 2,500 RPM will necessitate a relatively slow start from a stand still in the context of a drag strip run.
Additional details will be provided with each test event summary.
4.3 Test Criteria
Collection of reliable data constitutes a successful test event.
4.4 Limitations to Scope
4.4.1 Restrictions on randomization and other constraints
- Fuel supply limits – fuel rail pressure drop
- MAP sensor limit
- Combustion process – detonation
- EGT limits
- Turbocharger maximum speed
- Tire traction
- Project time available for planning, piloting, conducting
- Test area availability
- Ethanol availability
- Tuner competing priorities
- Test driver competing priorities
- Data analyst
4.4.2 Other Potential Issues
- Too much random variation (noise) – noise can drown out the signal. Can be resolved by increasing sample size through replicating treatments. Adding center points to design.
- Important uncontrolled nuisance variables – possible day-to-day variation. Deal with by adding day as a blocking variable in experiment.
- Restrictions on randomization – Possible to use split plot or strip plot experiment instead of fully randomized.
5.0 Method of Test
5.1 Test Methods and Procedures
The test will be conducted by following a design of experiments process. Performance data will be recorded, analyzed, compared against projected performance estimates and objectives, and then updates made to try and optimize response values.
5.2 Support Requirements
- Availability of a drag strip facility will constrain data collection opportunities.
- Availability of Ethanol fuel in the test area is limited and may lead to progress delays.
6.0 Project Management
6.2 Reports
6.2.1 Product Test Results
- Baseline tune
- Stratified E30 Rev 1
- Stratified E30 Rev 2
- Stratified E30 Rev 3
- Stratified E30 Rev 4
- Stratified E30 Rev 5
- Stratified E30 Rev 6
6.2.2 Test Result Summary
A summary of test results will be placed in this space as information is collected.
7.0 References
Stratified Automotive Controls website
Shuenk IS38+ turbocharger product webpage