Intake manifold modification: Increase engine performance

Air filter
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An intake manifold modification is among the most basic and affordable engine modifications any car enthusiast can tackle. Every day, we can come across many people on the internet interested in how to increase engine performance. We, therefore, decided to write an article focused on this topic.

In this article, you will learn in particular about the possibilities of how to increase the performance of a naturally aspirated engine by adjusting the intake manifold. Please keep in mind that this is not a guide, and everything you do is at your own risk.


Performance modification: What do I need to know?

Many modifications to increase performance are very expensive, and you will not always feel enough performance increases as expected. To achieve the highest possible increase in performance, it is necessary to make several adjustments simultaneously.

It must be understood that any modification of small displacement engines and three-cylinder engines is just an unnecessary waste of money. People who want to modify their one-liter MPi or three-cylinder HTP need to understand that no matter what they do, nothing will ever come of these engines.

These engines are doomed in terms of performance. For the money you would put into modifying such an engine, you would get only a tiny performance increase. Therefore, it is better to save money and buy a more powerful car in the first place.

So let's get to the point. Here are some tips on increasing engine performance by modifying the intake manifold or replacing the classic filter with a sports (cotton) filter.

Performance air filter

Air filter

Probably the simplest and cheapest modification is to replace the classic paper air filter with a cotton one, which has a greater airflow. However, many people say it is a waste of money and that changing the filter is unnecessary.

Several companies did tests, and it was confirmed that the cotton filter could increase the performance by a few horsepowers, roughly about two to three. Hold your laugh for now.

Obviously, there is no noticeable increase in performance after this modification. Therefore it is combined with other modifications. The long lifespan of the cotton filter is also an advantage, if it gets dirty, wash it, and it is like new again.

Adjusting the intake manifold

Adjusting the intake manifold can be done in two ways:

  1. Direct suction
  2. Impact suction

1. Direct suction

In this method of adjusting the intake pipe, it is necessary to make the new intake pipe as short as possible and to have as few folds as possible. At the same time, however, it must be ensured that the intake pipe is not located too close to the engine, thus avoiding hot air intake.

2. Impact suction

This type of intake modification is much better but more complicated because the air gets into the engine by thrust, which means that the faster the car moves, the greater the thrust of air acts on the front of the car.

As with direct suction, the new suction pipe must have as few folds as possible, be as short as possible and not suck in hot air. In the case of blast suction, it must end at the place where the greatest blast of air acts - hood, bumper, area of ​​fog lights, mudguards, and the like.


The best materials for adjusting the suction are plastic, rubber, silicone hoses, or hoses and pipes made of light alloy, mainly because of the excellent heat insulation.

Modifying the intake pipe and replacing the air filter are the cheapest and easiest modifications on your engine. In the next article, you can read about other options for increasing the performance of your car.