6.4 Compound Turbo Testing

dino graph for 6.4 turbo


Got the KC Turbo Harley test truck back on the dyno again. We added a Midwest Dual Fueler kit, way more work than we originally anticipated. Dyno results above, For those who have not been following our write-ups, we are doing a lot of R&D on the turbo side to build the best drop in compound turbos possible for the 6.4. We don't wanna just do the same old stuff everyone else has been doing. We are still just working on the drop in Atmo turbo. Results have been super impressive. I can't believe how much power we can squeeze out of these trucks with just a drop in Atmo turbo


  • Stock injectors
  • Midwest dual fuelers
  • EZ Lynk SOTF tunes from Chris Buhidar with Truck Source Diesel
  • No Limit Diesel intake and cold side CAC Tube
  • Engine was built by Jared Alderson from Kill Devil Diesel
  • Turbo: Stock HP Turbo, Atmo is a KC 75mm with 4" inlet, ported cover, anti-surge ring with modified MAP groove. Larger upgraded s400 turbine wheel and bearings

If anyone remembers our last test, we were starting to drop Rail pressure on a 2200us tune even with a brand new fuel system on a single pump. Made good power but could be inconsistent in between dyno runs so it was making it hard to do back to back testing. Well that problem is solved now, Blue run was dual fuelers on the same tunes as before, 2200us. ZERO power gain over a single pump. This is still a good representation of what stock would expect if you can hold rail. As long as you hold rail on a single pump then there are no gains. We get asked that question a lot, Green run was turning the truck up to 2400us, which is a pretty hot tune for these trucks. 2200us - 667hp 1327tq 2400us - 708hp 1426tq. Truck runs SUPER CLEAN at WOT. This setup is just begging for more fuel which is crazy because it still has the stock HP turbo, We need to get a higher reading map/ebp gauge on the truck. 2900rpms maxes at 50psi at 2900rpms with 69ebp. It just barely maxes out the ebp gauge at 73psi at 3300rpms. If I was to guess it is 53-55psi boost and 75psi ebp comparing to previous runs and how they rise.

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