Back to the original question. IF you want more power from an MB turbo diesel, add an intercooler and turn up the boost & fuel as much as the EGT's allow. Forget propane. Forget touching the injectors, prechambers, etc. Porting the head is great but expensive and time consuming. The intercooler is mostly a bolt-on, but will require internal IP tweaking to increase fuel delivery - you can NOT just turn up the ALDA and expect top-end power gains! Mosselman Turbo gets 20% power gain and 25% torque gain on their 602/603 intercooler kits, and I'd expect you could get at least that with a decent intercooled 617.

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