A throttle body is responsible for driving air into the intake manifold and sending that air’s measured volume to the ECU to match the air’s volume with the right amount of fuel.
The volume of air-fuel mixture the engine can hold or flow through it determines the overall power produced by the engine. That is why increasing the displacement of the engine increases power.
The throttle body operates the air control valve, which controls the throttle blade and opens and closes depending on the load requirements and how much the gas pedal has been pressed.
The throttle body can be a direct mount and bored to increase surface area, or it can be ported, increasing the surface area and letting in more air volume while increasing the air velocity. There are other effects that a ported throttle body has on the engine; let us see if they are worth having a ported throttle body.
How Is A Ported Throttle Body Made?
A ported throttle body is made by boring the front end or opening at an incline and doing the same with the rear, which connects to the intake manifold in such a way that the throttle plate or the throttle blade and the circumference of the throttle body around it remain same so that the stock throttle plate is used to open or close off the airflow.
Whereas, in a bored throttle body, the whole throttle body is disassembled as the opening is bored to the end, and a new custom throttle plate or throttle blade is installed because a stock one will have a gap between the throttle body and the plate.
Advantages Of Ported Throttle Body
The purpose of not boring a throttle body all the way through but instead boring at an incline and leaving the circumference the same around the throttle plate is to create a bottleneck.
This bottleneck uses the principle of physics that tells us that an inclined decrease in surface area and then increasing it again creates low-pressure zones. This accelerates the air as it passes through the throttle body, increasing the air velocity and even driving more air into the intake manifold.
This creates a sort of forced induction. Due to an increase in air velocity, fuel vaporization is better, resulting in better acceleration.
Disadvantages Of Ported Throttle Body
A ported throttle body is for people looking for better engine performance, but it’s not guaranteed that it will improve performance for all engines. Small engines below 1.8L might not produce a completely fruitful outcome, and the bottleneck might end up choking up your engine.
Another disadvantage of ported throttle bodies is that they might make the car run lean, which voids the manufacturer’s warranty. Your car insurance will remain intact because the boring won’t affect the structural integrity of the throttle body to a certain point of boring.
Does Porting a Throttle Body Increase HP?
Well, the short answer would be yes and no. The HP figures claimed by the manufacturer and produced by the car occur at a certain RPM or a specific RPM range. When you floor the gas pedal, the RPMs rise, and the engine produces more torque with the rise in RPM.
The max torque is produced at a certain RPM, thus producing max HP. Ported throttle body increases your car’s acceleration and response time so the engine can quickly reach peak power producing RPM.
The quicker you reach the peak power-producing RPM, the faster you can have your engine at peak HP. So in a way, you feel more HP is being produced, but in reality, it’s just an increase in responsiveness and a better range of power-producing RPMs.
Is It Worth It?
It is worth it if you have an engine with a large displacement and want to improve performance without having to swap out anything or add anything new.
It may not increase HP by that much, or at all, but you will enjoy the performance anyways. If you’re looking to add a system of forced induction to your engine, i.e., turbo, this might also be a good idea to improve the boost threshold. Boost threshold is the range of RPM when the turbo is spooling up and producing boost.
Do You Need A Tune?
Well, you know what a ported throttle body will do; you can do a tune to get more bang for your buck. The ported throttle body doesn’t require a tune, but if you fine-tune your car or have it done by a professional, you might be able to get around 20 more horsepower.
Besides the tune, you can add a throttle body spacer plate. The throttle body spacer is bolted on the rear of the throttle body downstream of the airflow. It has pieces of metal that direct air into the intake manifold, and the spacer allows more air volume to pass through higher pressure.
With a cold air intake and a good tune, you might be able to squeeze up to 35HP or even more, depending on the person doing the tune and the parts you buy.
Porting a throttle body requires skilled labor and equipment such as a micrometer and vernier’s caliper. All in all, it will cost around $30-$70, depending on the frame size of the throttle body. If you buy a ported throttle body, that would cost about $100-$200, depending on the car’s make and model. The throttle body spacers go for around $20-$45.
A ported throttle body is a way of enjoying your car more due to increased performance. An increase in performance doesn’t specifically mean an increase in HP, but it improves the engine’s overall responsiveness. You will notice better acceleration and a better engine feel.
Ported throttle bodies are a harmless, risk-free, and safe way to improve performance for people who want to keep their cars reliable. The manufacturer’s warranty will be void if caught, but auto insurance might remain intact since you use a stock part. If you wanna explore the “HP increase without risks” zone, you can add throttle spacers, add a cold air intake, and fine-tune your car.
The company tunes the engine depending on the car usage and customer base. If a vehicle is advertised as fuel efficient, the manufacturer will tune it as fuel efficient rather than performance. So you can always try to tune the car for better performance, but better performance requires better airflow, fuel flow, cooling, and ignition timing.
If you plan to increase performance safely, then make sure to get all the work done by a professional. If the tune or part placement is bad, then there is a good chance your car won’t reach the emission standards or have the correct air-fuel ratio. This will make the car run either rich or lean or increase fuel consumption. A ported throttle body is worth it, depending on what you’re expecting from it.
The misconception around ported throttle bodies is that they will significantly increase HP. In reality, the HP increase is usually within the standard deviation affected by environmental, fuel, and surrounding factors.