For every subaru owner the stock performance power is enough at first. I believe that 265 or 305 hp in the stock STI is enough for the first owner as well. Unfortunately, the longer you drive, the more you realize how weak the stock map is, not even in terms of power, but in terms of torque progression. Of course, what's the first thing you do in the evening? You go to the Internet, check YouTube, where you see a lot of American 500-horsepower subaru‘s, and you dream about them too.
So let's talk about what you need to do in order to revive your series STI, give it some horses and a little bit of cruelty.
the biggest set back when trying to gain power are your catalytic converters. Catalytic converters are the biggest drag on increasing performance. We therefore replace the first catalytic converter immediately after the turbo which gives it more free flow which is called a „downpipe“. Thanks to this change, the air from the turbo is not sophicated and not restricting air flow and can fly beautifully out of the exhaust pipe air way. After a long trial of downpipes from different manufacturers (Invidia, Magnaflow, various Chinese copies and self-made), we ended up with the manufacturer MG. These downpipes do not crack for us, they have a very nice precise processing and they fit without any modifications. For models for the year 2001 – 2007 you can buy a downpipe here and for models 2008 – 2017 here. If you really like your Subaru and like to pamper it, I recommend buying in addition to the downpipe thermal tape from the manufacturer DEI which is listed on our website. It goes without saying that each downpipe should be fitted with a exhaust seals.
So we solved the exhaust gas flow. However, in order to tune safely, you need to ensure 100% fuel distribution to the engine. For this reason, we change your old stock fuel pump for a much more powerful pump, most often for products such as Walbro and Deatchwerks. We do this why? Because we change the fuel pump mainly when the old pump no longer works at 100% and you dont want to take any chance so it’s better to change it out. By having the pump deliver less fuel to the engine than the tuner needs, the mixture could be lean and could cause irreversible damage to the engine.
During the time we drive and tune Subarus, we have met a lot of experimenters who change intakes, intercoolers or even downpipes in various ways. Believe me, it has been confirmed to us more than once that the stock components are the best and absolutely sufficient up to 400 hp and 600 NM. We offer this set at a discounted price for beginner Subaru owners. Do not forget that if a Subaru has catalytic converter removed must always be tuned. If you do not tune it the turbo will over power itself with more air which could cause the turbo not to work properly, just take in consideration. You can also use these components in the turbo Forester, Levorg or Impreza WRX.
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