The real story here is where the easy power ends. On the Duramax L5P, once output is already around 505-510 flywheel horsepower and roughly 1,022 lb-ft, the next weak point is the turbocharger turbine. That means the path forward is no longer just about adding more tune—it’s about fixing the airflow bottleneck. The same thinking carries over to the 6.7L Cummins. We’ve been working the charge-air side on that platform, including intercooler development and competitive analysis, because air handling becomes critical when you want clean, usable power. The tuning plan also includes the Banks Derringer Tuner, but the bigger point is simple: once you get into this power range, hardware has to support the tune or you run out of room fast.
When asked what the first turbocharger modification would be on a deleted, fully tuned L5P, Gale's answer was direct: the turbine side is the first area to address. In this context, the turbine is treated as the limiting factor once tuning freedom is available, making it the logical starting point for improving the turbocharger package.
The discussion then turned to measured output with the Derringer. Flywheel horsepower was described as being in the 505 to 510 range, while flywheel torque was about 1,022 lb-ft. Those figures place the setup at roughly the threshold many diesel owners consider a benchmark for a street truck.
That benchmark was framed as a kind of industry holy grail: a truck that can deliver 500 horsepower and 1,000 lb-ft starting from a stock showroom platform. In that sense, the L5P combination under discussion is notable because it reaches that territory while Banks continues refining the package and evaluating what comes next.
After covering the L5P, the conversation shifted to the 6.7L Cummins platform. Gale noted that he also owns a 2016 Ram 2500 Crew Cab 4x4 with the 6.7 Cummins, and that work is already underway on supporting hardware for that truck. The next phase of development appears to be moving toward that platform while the L5P work continues.
A major focus on the 6.7 Cummins has been the charge air cooler, or intercooler, along with related components. The 2013-and-up trucks were identified as using the same charge air cooler configuration, which makes that model range especially relevant for product development and competitive comparison. Banks is in the final stages of competitive analysis on its charge air cooler product for that application.
Tuning the 2016 6.7 Cummins was described as less straightforward than a simple in-house flash. Instead, the current landscape involves workarounds that require combining tools and services from multiple outside sources, including separate companies and cables to enable reflashing. The implication is that calibration access exists, but the process is fragmented and less elegant than Banks would prefer.
Despite those tuning complications, the plan is to apply the Derringer to the 6.7 Cummins as well. That indicates Banks sees enough potential in the platform to extend its existing power-module strategy beyond the L5P. In sequence, the engineering story here is clear: establish strong results on the L5P, identify the turbine as the first turbo bottleneck when tuning constraints are removed, and then carry the development effort into the 2013-up 6.7 Cummins market with intercooler work and a future Derringer offering.