How much peak power will my car make, what does this figure mean?
The general consensus is the higher the number the better, numbers sell. A 300hp car sounds much better than a 280hp car! But in reality, what can you tell by these numbers?
Peak Power / Dyno Figures
First of all quoted power and torque numbers are peak figures. They are the highest seen figures on a power or torque curve. They tell you what power and torque a vehicle is making on that specific dyno, on that specific day.
But are these figures are really only useful for bragging rights at the bar with your friends? For a true indication of how a vehicle will feel and where the benefits of tuning can be seen you need to assess the full power and torque curves. As they say, it’s the ‘power and torque under the curves’ that makes the difference.
Lets look at a dyno graph printout
In the below example there are three power curves. The purple is stock, the red is Revo and the dashed black line is hypothetical:
What does this mean?
On paper, the dashed Blackline makes the most power as it peaks nearly 10bhp higher. So does this mean your car is faster?
The simple answer is no. From 2400rpm through to 6000rpm the red curve makes a lot more power. At 3500rpm the red curve is 50bhp more than the dashed black curve. On the road, a car running the red curve (with a lower peak power output) would be a much quicker car. This is a good example of how a peak number can be very deceptive and not tell the full story. You can clearly see the difference in the area under the curves. And how much more the red curve has gained throughout the rev range in comparison to the dashed black curve. That fact that most of the time you will be at the lower rpm ranges. Means having more power at this point will be the greater benefit on the road. Rather than simply having a higher peak power figure.
Understanding Peak figures
Whilst an understanding of peak figures and power under the curve is essential. It’s just as important to understand that rolling road results can and do vary. They aren’t always a true representation of what a car will do in the real world. This is why it’s important not to base a decision about tuning and remapping your vehicle solely on peak numbers. There is a lot more to ECU calibration and making cars perform consistently on the road.
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