How To Build A Turbo Car The Cheap, 90s Way

If you want to get more power out of your car’s engine, a turbocharger is a great way to do that. Taking waste energy from the exhaust and using it to push more air into the engine, they are one of the best ways to achieve big gains in horsepower.

However, unlike simpler mods such as a larger muffler or a slight cam change, the installation of a turbocharged engine with atmospheric injection and fuel injection often requires a complete replacement of the engine management system, especially in older cars. . It’s not cheap, leaving a lot to stick to turbocharged cars with factory-set ECUs or to give up altogether. In the 1990s, ECUs were even more expensive in the last market, which led many to avoid them altogether. Instead, enthusiasts have used creative hacks to make turbo construction a reality cheaply, and it prevents you from doing the same today.

Fuel and time

The best solution is to use an aftermarket ECU for complete control over fuel and time, but this can be too expensive.

The reason why the installation of a turbocharger usually requires a revision of the engine management is due to the need to significantly change the fuel and engine timing. A spare, naturally aspirated (NA) fuel injection engine can measure engine airflow and engine load and use this information to determine the correct amount of fuel to inject and when to light the spark plugs.

However, with a turbocharger fitted, the pressure in the intake manifold, which is usually below atmospheric pressure for a NA engine, becomes positive under elevated conditions and this can completely confuse the spare ECU. At best, it returns to the “open loop” control method, ignoring its pressure or airflow readings in the engine. This uses a base table to decide how much fuel to inject and when to ignite, based solely on engine speed and throttle position. As the turbocharger injects much more air into the engine than expected by the ECU, the air / fuel ratio will be very low, which is likely to lead to a detonation in which the air / fuel charge in the cylinder detonates instead of burning at a constant speed. This can damage or destroy the engine in a short time.

A typical fuel pressure regulator with increasing speed. The two ports on the back are the fuel inlet and outlet, while at the front inside is the reference booster connected to the intake manifold.

Thus, in order for a turbocharger to work properly on an earlier atmospheric car, it is necessary to inject more fuel to match the added air introduced into the intake manifold. After all, that’s where the profit comes from. The best way to do this is by using a custom ECU that allows complete control over fuel and time charts. This allows the engine to be tuned to provide optimum performance right up to the detonation and damage limits, and provides stable, repetitive performance. However, there are other more basic ways to get the job done – increasing fuel flow and controlling the time – without the hassle of completely replacing the ECU.

In terms of fuel, the low-cost, low-tech solution is known as a rising-speed fuel regulator. Such a regulator increases the pressure in the fuel rail in proportion to the level of gain. This is often done in proportion – for example, a 10: 1 incremental speed regulator will deliver an additional 10 psi of fuel pressure for every 1 psi of thrust. The higher pressure causes the injectors to deliver more fuel for the same duty cycle. This makes it possible to increase the fuel flow in the engine, as the turbocharger unwinds and provides a boost without having to make any changes to the fuel card in the commodity ECU. These devices can be purchased cheaply, often with different interchangeable diaphragms, to change the ratio and to some extent to adjust the fuel supply, albeit with much less finesse than a properly tuned fuel card.

The Apexi Super-ITC has been a popular ignition timer since the 1990s. The high cost of after-sales ECUs over this period has led to the popularity of such “piggyback” solutions.

From time to time there are several options to avoid blasting. In cars where there is such a setting, the cheapest method is simply to reduce the base torque of the engine to a lower level. This will keep the time lower, hoping to avoid detonation when working at high revs and high gain levels. However, this means that at lower revs and lower loads, the car will run at suboptimal times and will sacrifice power and handling and is likely to cause poor engine idling. This may be acceptable for cheap racing versions, but can be frustrating for a street car.

Alternatively, a timing box or ignition controller can be connected to the vehicle. They consist of a microcontroller that monitors signals such as intake air temperature, rpm, engine position and gain. When the timing box detects gain, it intercepts signals from the engine position sensors and leads them back to the ECU, shifted so as to change the time the ECU triggers the ignition pulses. Popular models include Bipes ACU for Mazda Miata and Apexi S-ITC for a wide range of JDM cars. Often these synchronization boxes are also used to tune cars with turbochargers, working with larger turbochargers and other major improvements. Sync boxes usually offer some adjustment through DIP switches, LED displays, and knobs that can be adjusted to determine the exact level of time delay desired to protect the motor from detonation.

ECU swaps have become the preferred hack

One thing you will notice when you research these devices is that most of the posts in the technology forum date back to before 2005. This is because with the advancement of technology, ECUs of aftermarket goods have become cheaper enough to make them a more attractive option. The ability to properly dial a fuel and time card, compared to trying to push and boost the ECU stock to deliver huge amounts of extra fuel and less time, usually results in a car that drives smoother, more reliably and is less likely to blow up. It is also much easier to set up. However, these parts still have a place in the scene. They are used for constructions with the lowest budget, such as the Broke and Boosted project, or in racing series like 24 Hours of Lemons, which include restrictive budget constraints. These techniques are also relevant for recharged NA engines as well as carburetor turbochargers, although they replace increasing speed regulators. carburetors with reference amplifier and time interceptors for ignition systems ready for amplification.

A modern engine management system may be the most reliable and accurate way to set up a powerful engine, but this is not the only way. However, don’t expect to get much help from the wider automotive community if you try such a design. The tricks and techniques are largely sent to the dustbin of history, so you may find yourself reviewing old manuals and need to troubleshoot. But if money, racing rules, or just the sheer thrill of doing things the old-fashioned way puts you in this situation, we hope this guide gives you the best possible success. Good luck and happy healing!

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