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Message: [QUOTE="Charles, post: 1295175, member: 103"] I watched Darrin Morrison pull low to mid 700 or so on fuel one particular day, rolling massive coal, I mean blotting the sun from the sky. I asked what that was all about and he was saying how the problem was the tiny ass injectors. I was thinking damn.... you're saying the problem was not [i]enough[/i] fuel.... He looked at me strange. After he swapped to bigger injectors and later pulled a little over 920 on fuel with way less smoke I understood. The problem was how [i]long[/i] it was taking to get the fuel in the hole. A small nozzle will make less power all while smoking like a train, running hot and consuming resources. Going to a [i]faster[/i] injector doesn't mean injecting more fuel quantity. You can inject the same quantity far faster, make more power on the same fuel (because the window is more efficient) smoke less and run cooler. So yes, there are very good reasons to run a large injector and dial the duration back. Most of the time the programs are way too stretched out in the first place because they were meant to stretch the slow stock nozzles out to try and get fuel in the hole. It's not so much that you need to dial the fuel down, more just put it back where it was supposed to be before you started dragging everything out trying to get a stock nozzle to perform a task it's too slow to do efficiently. Sadly, if you just removed the program and went back to stock you would probably be pretty damn close! Although driveability at lower desired power would be jumpy as hell. If always dragging out the smaller nozzles was the answer instead of a larger nozzle at shorter duration then you wouldn't see OEM decisions on the subject use larger nozzles for higher output versions of engines instead of just pushing harder and harder on the same nozzle size each time. Sometimes there's enough reserve on a stock nozzle to accommodate modest power increases without becoming inefficient, but as the power climbs, it doesn't take much before a larger nozzle will win on power, smoke and EGT all at the same time. Otherwise the stock nozzle was spec'd to big for the intended power in the first place. Nozzles are picked for efficiency at a given power. "More fuel" as a concept is the problem. It's one dimensional. The problem is fuel per time. 400cc of fuel over 20 degrees of crank travel is quite a different animal than 400cc of fuel over 40 degrees of crank, yet each one uses the EXACT SAME amount of resources from the pump, while one makes tons more power at lower EGT with less smoke! The same fuel happening quicker is worth its weight in gold. [/QUOTE]