Above: Surbo (at the centre inside a black housing) clipped to inlet of air filter of Honda Civic 1.3 Hybrid.
A hybrid vehicle is one with an internal combustion engine (petrol or diesel) that is coupled with an electric motor, powered by batteries that are charged up when the engine revs or when the vehicle slows down, using engine brake regeneration. At low speeds, the electric motor will move the vehicle, and later the engine will be started and they will work in combination. When the charge runs out, for example on a long climb, the engine will work alone. How can the Surbo benefit such vehicles?
Firstly, hybrid vehicles have downsized engines, and when there is no charge left in the batteries, they will be underpowered. In this case, the Surbo's added torque and higher revving capability will aid the generation of electricity.
Secondly, the Surbo is known to push vehicles further than normal when the accelerator is released completely, because the engine back pressure formed charges the Surbo and it increases air density to the engine. This means that the Surbo-equipped hybrid vehicle will charge and store electricity at a higher rate during engine braking. The resultant increase in charge stored will mean more distance possible on just electricity, or better acceleration on its own, or in combination with the engine.
Thirdly, there could be more fuel saving and more quiet driving with the electric motor alone due to the increased charge stored.
The Surbo has been installed in a Honda Civic 1.3 hybrid (with cvt gearbox). The owner said that for gentle acceleration, only 2500 rpm was required from the engine, whereas 3000 rpm was needed without Surbo. This showed the improvement in low end torque. The hesitation was gone, and the drive had become smoother. The charging of the battery became faster--previously he had to slow down whenever battery level was low, especially upslope. During faster acceleration, the engine could go above 4000 rpm, previously not possible.
The Surbo has also been installed in a Toyota 1.3 hybrid in Malaysia. If you have a hybrid vehicle and wish to improve its performance, please come and try the Surbo.