ModUrStang's GT850R Tuning software development

Mike from Modurstang reached out to us to help him with his awesome 'GT850R' Mustang GT build. After already having one catastrophic engine failure with another tuner we were given the responsibility of tuning the new engine in this killer bee 🐝 ———————————————————


- 9.5:1 Low compression ratio block
- MMR supercharger cams with lockouts
- Stage 2 Whipple Charger w/ 3.500” 10 rib pulley
- Kooks Headers w/ Sports Cats

An engine built to this spec is not something that you can just tweak the current map for. Essentially a WHOLE new tune file needs to be engineered to suit such modifications.

This car was previously suffering from multiple misfires detected by the ECU as the tune wasn’t built to accommodate aftermarket cams with phaser lockouts. This meant that the ECU was picking up on false misfires due to the MMR cams which then lead to a cylinder injector cut / closed loop fuelling fault which resulted in a target AFR of an extremely lean 16:1 at wide open throttle! (Cause of engine failure!) We ironed out all the issues with a custom written tune and the car is now running 600rwhp & 460wtq!

Unfortunately the much lower compression ratio block in this car meant that we lost quite a lot of power and torque in comparison to if it was running the stock compression ratio of 11:1. The 9.5:1 alluminator blocks needs 20+ psi boost before they start making the numbers whereas this is running a 13.5 psi pulley

Still some bits to do on the tune, let’s see if we can find some extra ponies!