POSTED BY Steve
Jeff's awesome 2017 Subaru STI finally gets his full power tune and makes 650whp on the HMS Mustang Dyno! Steve pushed the tune as far as the GTX3584RS would go and she ended up making 40psi of boost on E85 Fuel, we hoped to make more but this turbo just wont give us more. Jeff has future plans to change up the turbo and go for his ultimate 700whp goal so stay tuned! Go check out the Customer Cars section for more info and full specs on this beast!