The big news for the 2013 Shelby GT500 was that for the final two years of production, this Ford supercar would make 662 horsepower from its 5.8 liter V8 engine. That’s a whole mess of power, and with the car coming with a factory warranty, other aftermarket companies have struggled to keep up in terms of raw numbers.

But more than a year after the 2013 Shelby GT500 debuted, ROUSH Performance is now offering a Stage 3 ROUSHcharger kit that can squeeze an incredible 675 horsepower out of the standard Mustang GT’s 5.0 V8. So how’d they do it?

Utilizing a 2.3 liter ROUSH R2300 supercharger with a 80 mm pulley, the Roush Stage 3 kit includes upper and lower aluminum intake manifolds, a twin 60 mm throttle body and high-flow 45 lb. fuel injectors. Combined with a high-efficiency intercooler system and a plug-and-play wiring harness, this kit adds a whopping 255 horspower and 195 ft-lbs of torque. That brings total output up to 675 horsepower and 585 ft-lbs of torque, which is right on par with what the 2013 Shelby GT500 offers.

At just $7,199, these kits are a lot cheaper than that Shelby, and if you already invested in a ROUSHcharger system, then the upgrade kit will only run you between $1,000 and $1,500. This cost-conscious alternative to the GT500 gives you all the power, without the high cost. Can’t complain about that!