S63TÜ Stage 1 E-Flash Performance ECU Software ESS S63TÜ Stage 1 Performance E-Flash ECU Software 700+ HP / 680 lb-ft tq The E-Flash S63TÜ software is a full OBD2 solution that does not require sending in the ECU or opening the ECU in any way. All emissions control systems remain active... MSRP: Now: $1,349.00 Add to Cart Compare Selected