The graph above shows increased torque and power over the whole rpm range (thick line=Surbo, dotted {faint} line no Surbo). The torque increased by 108/93 Nm, or 16%, and is more accessible as it peaked at 3300 rpm instead of 4300 rpm originally. Power was up by 69.4/65=6.7% at the maximum.
The Twin Surbo (thick line) was even more torquey, as its torque peaked at an even lower 2850 rpm (103.5/87.7=18% more at this common cruising speed). This makes driving or overtaking feel good on the highway.
This graph shows that the Twin Surbo was stronger in torque from 2450 rpm to 3150 rpm. Therefore for those who do not rev much, or who cruise* in 5th gear between 90 kph and 115 kph, the Twin Surbo will help them save more fuel. For super highways where speeds exceed 115 kph (such as the Malaysian highway), the single Surbo will save more fuel due to greater torque. This also means that the single Surbo is better for revving between 3150 rpm and 4900. The Twin Surbo's power peaked at 5100 rpm, earlier than the single Surbo, and this may mean different tops speeds depending on the gearing.
*Gearing (5th of this car): 110 kph at 3000 rpm, or 36.67 kph/1000 rpm, or 22.63 mph/1000 rpm.
This is the time graph comparison between the single Surbo and the Twin Surbo. The Twin Surbo (faint line) had more torque than the single Surbo (thick line) from 1.5 seconds to 2.7 seconds. The single Surbo led from the 3rd to close to the 6th second. The Twin Surbo reached its peak power of 69.2 HP in 6 seconds but the single Surbo took 8 seconds to hit its maximum of 69.4 HP. This may explain why the Twin Surbo is often faster for 0-100 kph times. The difference at other speeds must be done by road testing.
Power is maximised when the Surbo is activated (as far as possible like in How It Works). The peak power was 71.65/65=10% more this way.
Please also read the better acceleration and higher top speed pages to see the power effect of the Surbo, and
Fuel Savings
for the torque effects of the Surbo.
Watch the video above showing how an engine revs with Surbo. Or watch it with the How it works page.
Above: video of Volvo XC90 T8 with Surbo, sprinting to 130 kph.
Above: video of Volvo XC90 T8 with Surbo, sprinting to 211 kph.
Above: video of Volvo XC90 T8 with Surbo, sprinting to 224 kph.
More torque and BHP (dyno test)
Quick revving (1/2 throttle to RPM limit)
If you are using a handphone to read this, you can press the above CHAT link to either call us, or to save our number to your contacts, and then you can message us by clicking the WhatsApp icon below.
