• Oxygen sensors and lambda control

    “Closed loop” refers to to the function of the system, meaning fueling is driven off of feedback from the oxygen sensor. Whether it is mathematically driven or table driven as the initial calculation for the amount of fuel needed, once we are closed loop, we are completely reliant on the data provided by the oxygen […]

  • MS41 tuning done remotely with the TRM flasher/logger

    We do a lot of our custom tuning remotely, often working with teams or shops as well as individuals. For tuning, we can fly to the car or the car can be sent to us, but we only need the car in person if we are needing to make physical changes that the end user cannot or […]

  • Heat, Energy, and Temperature

    Defining terminology: The total of all energy in an object is its internal energy. Heat is not the energy the body contains but the energy transferred from one body to another. We can make clear distinctions between temperature, heat, and internal energy. Temperature is a measure of the average kinetic energy of the individual molecules. […]

  • Launch Control, antilag, and rev limiters

    rev limiters, launch control, and antilag, are all different things. Antilag is typically accomplished via combustion continuing into the exhaust manifold to spin the turbocharger, but without accelerating the engine. This can be at light part throttle or zero throttle by the driver, but the system will hang the throttle open slightly (or slightly more […]

  • Differentials

    The purpose of the differential is to allow two wheels to turn at different speeds while coupled to one shaft. With the two sides coupled and no speed differential possible, as in a “locked” or “spool” or “welded” differential, the drive power when turning is substantially higher as slip is required on one side or the other. […]

  • Throttle Mapping on DBW cars

    In modern cars, there is no longer a “throttle cable” linking the throttle pedal to the throttle bodies. Now we have a throttle pedal that is a sensor/input to the ECU, and the ECU controls the throttle bodies. This is known as “drive by wire”. This has a number of advantages. One of the biggest […]

  • Vehicle Road Testing – Part 2

    In part 1 of this article, we discussed the principles for gathering coast down data. There are a number of things that can be determined from that data. We can calculate the aerodynamic drag and rolling resistance components of the total drag. The large component at high speed will be aero drag. It will vary […]

  • Roll sensitivity basic calculations setup

    Roll sensitivity describes how far the car will roll given a certain cornering force applied. Depending on the direction of the calculation, any number of the variables in this can be solved with a combination of knowns and assumptions. This can help not only calculate load on a given tire or suspension point, but allow […]

  • Vehicle Road Testing – Part 1

    Enhancing the performance of a vehicle isn’t always limited to making more power. Often more speed can be found by using less power to push the car through the air or along the ground. The best way to evaluate the effect of a change on a car is via controlled testing. We will need to […]

  • Cam Timing on the M50 based motors

    Dialing in cams can be tricky and take quite a bit of dyno time. Espeically on single vanos motors where we cannot play with cam timing independently in software like on the newer DVANOS cars. Cam movement/position must be adjusted manually, which means pulling the valve cover each time. Usually, on the dyno, when doing […]

  • Connecting a wideband to your TRM Datalogger

    The TRM datalogger can accept a wideband input via the “headphone jack”. The mono headphone cable necessary to interface with a wideband is included with the TRM Logger. It should be wired such that the tip is signal and the ring is ground. The output from the wideband controller should be configured as 0-5v. Standard linear output is the […]

  • Trouble codes on your OBD1 BMW

    Trouble codes on your OBD1 BMW

    If your BMW was manufactured between the late 1980’s and 1995, you should be able to pull diagnostic codes out of the car via the check engine light. To read these codes, turn the key to position two (run), but do not start the engine. Within 3 seconds of turning the key to position 2, you will […]

  • Boost Controllers

    Boost Controllers

    The primary control of boost in a turbocharged system will be the wastegate. The purpose of the wastegate is to bypass the turbochargers turbine, reducing its ability to make boost. (For more information on how the turbocharger works, see our article on turbochargers.) The wastegate will have a pre-set spring pressure. This can be adjusted […]

  • Engine Calibration and your BMW

    Engine Calibration and your BMW

    If you own a BMW manufactured after the 1970’s, there is some sort of computer controlling the fuel delivery to the engine. By the 1980’s all of the BMW cars in the US had some sort of fuel and spark control based on a piece of electronics. This computer would use various load inputs, such […]

  • Replacing the chip in your BMW

    Replacing the chip in your BMW

    This document will need photos for each step. While this article will focus primarily on the Motronic 3.3.1 system in the E36, the general information will apply to many other similar systems. The engine computer is often referred to as the ECU or the DME. The ECU is located in a cubbyhole behind the right […]

  • EWS on the E36 chassis

    EWS on the E36 chassis

    What is EWS? EWS is “Elektronische Wegfahr Sperre”. Don’t speak German? Then that probably wasn’t helpful. EWS is BMW’s electronic drive away protection system. The exact implementation of EWS on the E36 varied slightly through the years, but the general lack of long term reliability stayed the same. Key failures, antenna failures, and module failures […]

  • Oil quality and the life of your car

    Oil quality and the life of your car

    Engine oil gets contaminated over time by moisture, fuel, and particulate matter. Moisture generally being introduced as a byproduct of combustion, it is easily burned off by getting the oil up to temp. If you have a short commute, it is a good idea to take a long drive at least once a month in […]

  • Recommended chargers for flashing your BMW

    When flashing new software to your car, it is important that the voltage be held constant. That stability will ensure there are no problems with writing the data to the very sensitive ECU. Any fluctuations in voltage can cause a “bad write”, and as a worst case, “brick” the ECU. Voltage drops can be caused by a […]

  • Ethanol and your fuel system

    Ethanol and your fuel system

    It is becoming common to blend Ethanol with Gasoline in many states. Most stop at 10%, but there have been cases where higher concentrations of Ethanol has been found in pump fuels. Ethanol by itself is not bad. E85 (75-90% Ethanol, the rest Gasoline), if you have a readily available supply, can be great low cost high octane […]

  • Common Boost Leaks on Forced Induction M50-Series Engines

    Common Boost Leaks on Forced Induction M50-Series Engines

    There are a number of common problem areas on the turbocharged (and some supercharged) M50 based motors. With the OBD1 throttle body, there is a port on the bottom for the purge valve. It is generally best to disconnect this from the purge valve solenoid and cap the port on the throttle body, or install […]

  • Pressure Testing the Intake System

    Pressure Testing the Intake System

    Pressure testing the intake system on a turbocharged car is the best way to check for leaks. Any leak in the intake system can negatively impact the efficiency of the system. A leak after the MAF can also cause drivability and running issues. Pressurized leaks may not be apparent in vacuum testing, and may appear […]

  • Leak Down Test

    A leak down Test can be performed on a warm engine. The appropriate leak down testing apparatus will be required, along with a good air compressor. You should not have a cylinder leakage of more than 10% in any cylinder for a fresh/healthy motor. You should also not have more than 5% variance between any […]

  • Compression Test

    Compression Tests should be performed on a warm engine, with the fuel pump fuse/relay unplugged (and the fuel rail drained/depressurized), and the throttle should be held fully open while testing. These pressure values will be less at higher elevations, and can be lower on engines with more mileage. Aggressive cams or cam timing will also […]

  • Before you get on the dyno

    Before you have us tune your car, there are a number of important things to verify. If there is a “small problem” that is unknown before the dyno session, it can nullify The pre-dyno check list is similar to the pre-track check list: – Test the intake system for leaks – Check, clean, or replace […]

  • The Science Behind Bolts

    Materials can deform both elastically (returning to its original shape and structure) and plastically (permanently changed in shape, structure, or both). Every material under any sort of load (lets consider a fastener in tension) is deformed elastically, even if it is such a small amount that it’s impossible to notice. The strain (deformation, elongation in […]

  • Suspension 101: Swaybars & Roll

    Suspension 101: Swaybars & Roll

    Good suspension is meant to keep tires in maximum grip as much as possible. Maximum grip occurs when all 4 tires are in their “happy zone” temp and load wise. When cornering in a high-performance vehicle, load transfers from the inside tires to the outside tires due to the the lateral acceleration of the vehicle. […]