In this post we are going to talk about your turbo car and how to properly make power. But first, how does a turbo car work?
A turbo is fitted to the engine and the turbine inside of the turbo is turned by escaping exhaust gases. As the turbine spins it sucks in air and passes through an intercooler to cool down the incoming air. From there it enters then engine and becomes exhaust gas. Now as the engine speed increases so does the turbo, this creates higher boost and MORE POWER!
Power is limited to the size of the turbo and the components supporting the turbo. Turbo cars are pretty mod friendly, you can make a decent amount of power with little upgrades. First thing people usually install are intakes.
These intakes are less restrictive. They allow better and smoother flow of air into the turbo charger and they sound way cooler! Many intakes reuse the stock ducting from the front air damn to the intake. Cold air intakes usually relocate the filter to somewhere else (usually the fender well) to draw in cooler air.
Now, you want even more power! Let us throw in a catback exhaust.
A catback exhaust replaces the piping, resonators and muffler behind the catalytic convert (i.e. catback). There are many catbacks out there in the market, the one pictured is on a GTR. The style and brand is up to you, what you want is something big and free flowing. Most turbo cars with aftermarket exhaust run a 3in exhaust diameter versus lets say 2.5in diameter exhaust in a newer WRX. This allows exhaust gases to exit faster.
Alright we are getting somewhere, next up you want to optimize the extra air coming in and gases coming out.
Lets get into tuning! Pictured above is a popular way to tune your car. Cobb Tuning makes a device which reflashes your engines computer with a preset tune for certain modifications (an intake and catback is considered to be a stage 1 tune or reflash). This can be done in minutes and changed on the fly. If you want to get more into it you can bring your car to a tuner that knows your vehicle and have a custom tune done. Cobb isn’t the only company to make a reflash tool, but for simplicity sake we will leave it here.
So, we are making power and you are craving a bit more. We can improve exhaust flow even more by installing a downpipe.
Above is a comparison of a stock downpipe and aftermarket one. By installing a downpipe you are creating a full 3in turbo back exhaust. There are many downpipes out there and with many variations. You have downpipes with high flow cats (check your local and state laws regarding legalities) , some are divorced at the wastegate and some are open. Now we can’t say which is best for you, but we ask that you do your research to see what you want.
alright, home stretch… the last thing to do is to reflash your computer again to stage 2. This will optimize your tune to compensate for the extra flow of exhaust from the downpipe. We are now making heaps of power from our once stock car. It is amazing what untapped potential stock turbo cars have. These are only the basics, we can get even more into it, but maybe we will save that for next time. Remember to do your research regarding modifications and check with your local forums.