Now that we had a wider powerband, we wanted to increase our fueling over the entire rpm range. For this, we acquired a Power Pin from Dynomite Diesel, which would give us more fuel as boost came on. While the original fuel pin is cut on all sides, the aftermarket pin is cut only on one side. The cut face of the pin must be facing toward the front of the truck to work correctly; otherwise there will be no extra fuel as boost rises. With the governor spring in place and the pin installed, we were seeing 1-2 psi more boost than we had without the pin, which put us at about 33-34 psi. The truck hazed a little more black smoke down the road under full throttle, so we were hoping to see better numbers on the dyno. In order to free up any airflow restrictions that came with our fueling mods, we replaced the stock airbox and switched to a 4-inch exhaust. Check out how we performed these modifications and see if we made more power.
You can now take the governor spring off and put the higher rpm version in its place. There's a pin right behind the spring that can fall into your injection pump, so when you are removing the spring, keep one hand on the pin so it doesn't go anywhere. | 
Old vs. new springs. The "366" spring is the new governor spring, and should result in hundreds of more rpms of usable powerband. | 
The new spring is shown partially installed (arrow). One side is already in place, while the other end installs where Chambers' finger is pointing. |
Once the spring is installed, the last step before reassembly is making sure the lever (arrow A) goes behind the fuel screw (arrow B). If needed, you can back out the screw a few turns, but make sure to count the number of revolutions so you can get back to your "known" setting. | 
After the spring is in, just work backward until you have everything back together. Remember the timing marks on the pump and also check to make sure you still have full throttle after you reinstall the pump linkage. | 
After the spring, the fuel pin was next. To access the fuel pin, you must remove the banjo bolt (arrow A) and the screws that hold on the top of the pump (arrow B). |
With the pump top removed, simply lift up and the whole fuel pin assembly should come out. There is a nylon washer you'll also want to remove because a new, thinner washer is included with the Dynomite Diesel Power Pin. | 
Here is what the fuel pin assembly looks like. With an open-ended 10mm wrench and a box end 10mm wrench, the fuel pin can be removed. | 
Once the stock pin is removed, the Dynomite Diesel Power Pin can be installed in its place. The same flat metal washer and rubber surface will be reused. When installing the aftermarket pin, make sure the new nylon washer is used and the pin is installed with the deepest part of the pin facing the front of the truck, or in the nine o'clock position. If the pin is facing the wrong way or the old washer is used, the truck may not see full boost. |