Especially important for the early V8 Vantage with the 4.3L engine, adding power is often the first place people look when planning out their modifications.
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4.3L V8 Vantage
Of all of Aston's recent cars, the early V8 Vantage is the one most in need of increased power. In fact, the only real complaint anyone had about the car when it was first released is that it needed an extra 50-100 hp. From what I've experienced, it wasn't that the car was under-powered. 380 hp, while not a ton, was on par with other cars in its performance category at that time. Rather, there were two distinct issues that, when combined, made the car feel rather slow. The first is that the Vantage looked and sounded much faster than it was. Second, there's a considerable amount of lag between throttle input and engine response. That lag is a much bigger issue than many people realize.
Fixing Throttle Lag
The 4.3L engine throttle lag can be largely remedied with two changes to the car. One reduces the electronic lag that causes the throttle body to open more slowly the relative input you're giving the gas pedal. The other reduces the mechanical lag caused by an incredibly heavy flywheel.
4.7L V8 Vantage
In 2009, Aston Martin swapped out the 4.3L V8 engine for the 4.7L unit that would power the car until its replacement with the AMG twin-turbo 4.0L V8. The new, larger V8 fixed the common complaint of the Vantage needing more power, and it did so in a few ways. First is that the larger engine provided more horsepower and more torque. The extra 40 hp was a considerable bump, but what made the biggest difference during most driving was the extra torque. In addition to the extra power output, the factory also fitted a lighter flywheel. This reduced the throttle lag that plagued the 4.3L engines and got the engine into the higher rev range a bit quicker.
V12 Engines (DB9, DBS, V12 Vantage)
The power potential of these engines is greatly handicapped by the factory.