Drove a 3900 Impala, MY '08 today...

[IsaacHayes]

Yes, a 2.93 FDR will make the car seem slower too. My car has 2.89 FDR, and after driving a 2nd gen GP, which was geared way lower, then getting back in my car, I thought my car lacked power and response. But once I floored it I was flying A LOT faster than the GP was with the same engine but lower gears, and more weight. So gearing will change how a car just feels too, making it seem slower when it's not sometimes.

The 3900 in the impala isn't the performance model. Think of the last body style that had 3400, or a 3800 optional. So they upped the weight, and had to put a "bigger" engine for the 2nd optional engine.

The 3900 is a bit different beast with its VVT and variable intake though than a normal pushrod.

[Joseph Upson]

There are so many elements that affect performance feel in cars now that unless you are driving the exact same car over different engines for comparison you can't get a realistic seat of the pants feel anymore.

Electric throttles allow the computer to second guess your pedal input so you can press the accelerator to the floor and still be part throttle if the computer decides so. The type of fuel has an affect because the computers can now better detect the difference and limit throttle response to avoid detonation, then there is gearing, weight and suspension differences. A friend thought my 85 2.8L firebird was faster than my 86 TPI IROC because the bird had a 5 spd and IROC an automatic, shifting the 5 spd gave a deceptive increased performance feel.


Anyway I'm almost ready to install the 3900 in my Fiero and will email the appropriate authorities on the forum for information on how to access the additional space I was authorized for donating (something we all should consider doing) so I can post the swap info, it's bolted to a 6 spd and is twin turbocharged, with .60/.63tur T3s.