Why is the Z slower than comparable cars?

Jordo!

Unless the OP is talking about heavily modified boosted cars, with the possible exception of the latest iteration of V8 Mustangs/Camaros (and I believe for more money and coming with a lot more torque) the Z is still around the head of the pack on N/A performance, especially for the money.

On that note, the latest V6 Mustang has a 3.7 that makes less power and about the same torque as the Z and is NOT faster in a straight line, stock vs. stock.

Also, compare the Mustang Ecoboost (more powerful than their V6) to the Z
http://fastestlaps.com/comparisons/n..._ecoboost.html

vs. the much more powerful Mustang GT, which also has a better power to weight ratio
http://fastestlaps.com/comparisons/n...ance_pack.html

It's about even with the 2015 WRX STi -- the slight advantage for the WRX likely being due to the AWD.
http://fastestlaps.com/comparisons/n...5_wrx_sti.html

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