Just got my ECM back, DDEC III, 500+15% 2210 rev limiter, I've got a buddy that just laid down 504 to the wheels with the fan on in salina KS with a 485 with 15%.

sounds like some good #'s ,but I would think the MPG would go away some :U:

On the DDEC computer-controlled injectors, is there anything to gain with the old "vice grips over the fuel return line" trick? Or does it see the pressure in the head and adjust the injectors accordingly?

With the DDEC ECM, there is no fuel pressure sensor. Only fuel temp. They are electronicly controlled and use an orfice fitting in the back of the head to regulate pressure. Closing the gap (trying to raise press) will do nothing for the injectors. DDEC uses logic controll. Two timing sensors (cam&crank) monitor injector response times, then the ECM regulates from there. Raising fuel pressure will not help. The ECM will just make the injectors close faster.

One trick i have seen done is to install a resistor in the fuel temp circuit to make the ECM think the fuel temp is cooler than what it is. Have not seen anything proving that this work.

Give this sight a look. They're doin some pretty impressive stuff with Detroits. Makin em run with Cat and blowin Cat's mpg's out of the water.

The Pittsburgh Power N-14E Cummins and 3406E Cat Electronic Upgrade Kit

ain't hard to blow a new cats fuel mileage away I do that with my old series 60 stock:U:

We have a couple guys running the new c/15 cats getting 3.9 to 4.5 mpg, our new DDEC engine and Cascadia chassis are getting 6.9 to 7.8 pulling 105500 gvw. Pretty insane difference. Some guys save in fuel, the cost of a new truck payment.

So far my fuel mpg hasn't dropped. But I haven't had any real good way to test it, still did close to 5 with a 45mph side wind:argh: Been havin to stand on it hard this whole trip. Same fuel mpg, with added power....I'm happy.

you can change cal codes of injectors, if the turbo is wastegated you can adjust the rod so it opens later, you can put a resister in the boost sensor harness to show the ecm higher boost. thats pretty much it unless you want to spend some money on hard parts and programing to turn it up. hard parts are turbo cam and injectors. there are 800 hp series 60's out there you just got to know somebody at the factory to allow you to program one. its deffinetly a bad idea to drill out the r80 fitting. you will burn up your injectors.

At UNOH, we had a 60 series on the dyno all the time and the teacher tried different things to it to try and match the signature 600 we also had on another dyno.

both engine were egr engines, to keep them close.

one thing i do remember him doing is moving this fuel temp sensor from the back of the head to the inlet on the engine. little cooler fuel there.

i think that was right. lol been 3 years since i was in school .