S650 Mustang Stage 1 Upgrade
Upgrade your 2024-2026 S650 Mustang GT or Dark Horse with our Stage 1 performance packages at Miller Mountain High Performance in Pottstown, PA. Choose a premium cold air intake for improved airflow and throttle response, add a custom Shoemaker tune for optimized power on 93 octane or E85/flex-fuel, and complete the build with an aggressive axle-back exhaust for that deep Coyote sound. Configure your ideal combo below—professional installation included—and experience real gains today! Call 610-326-7000 for quotes.
Google Reviews
What Our Customers Say
"I trust these guys"
“Fantastic performance shop!! Miller mountain went over and above to ensure my truck got tuned properly. I brought my truck in with a trash remote tune and they took the time to dial everything in to perfection. Super friendly service and very easy to deal with. I trust these guys with my vehicles and will be back for all my tuning needs in the future.”
- Justin D.
"Friendly and professional"
“First time customer here and these guys are the real deal. They installed a cat-back exhaust system on my 10th gen Si. Mr. Miller and his team were very friendly and professional. I am extremely happy with the work they've done. The shop is clean and the waiting area is cozy. I highly recommend this shop!”
- Drew
"Definitely have the knowledge"
“Had headers installed and engine and transmission tuned. Would like to thank Art and Logan for the excellent service and workmanship. These guys definitely have the knowledge and know how to get things done right and in a timely manner I would recommend this auto shop for repairs and high performance projects. I also think I made a new friend there his name is Rocky the dog. Thanks for everything guys.”
- Mike L.
