bully dog box

[DIESELMAN]

First , I am a controls and electronics engineer, so I believe I know the thinking and practicality behind the design and mods, but I'm not a Dieselier, yet



Yes, the ECM has a limiter, it appears to de-fuel beginning at just below 3200, and I have heard that it doesn't come apart until it reaches 4200, so I guess its safe. I've seen 3600



The flare is caused by the Rail Pressure still being high, and the ECM not completely ever not firing the injectors less than a certain duration (cooling?), when you remove the load, push in the clutch, the pressure bleeds down through the return line and the injector orifice and is burned, the engine speed naturally rises. It is worse when getting on it with the EZ on 4 I think, and not good for the clutch either.



I think the 'wasted' fuel would amount to microliters and is insignifigant and the process to shear the fuel would be overly complex for an irrelevant result.



DM

 

[SRadke]

The highest pressure you saw on a stock truck was 1600 psi. Was this a HO or SO engine? I have often wondered how they account for the diffrence in the software.



I think I'm with you now. The pressure actually is increased from stock, just not beyond the design limits of the system. You mentioned what sounds like a high pressure bleed off on the rail. This begins to bypass fuel at 23,000 psi. If all this is true then one could assume (and we all know what that does) that the system was designed to operate at that pressure. The question then becomes how much pump life, if any, will we loose because of it? Out of curiosity I also wonder how much heat we add to this fuel after pressurizing it to 23,000 psi and leaking it through a pressure relief.

-Scott

 

[DIESELMAN]

One more 0.



I don't think it ever leaks out of the pressure releif, and if it did the temp would drop, not increase.

 

[randyn]

MPG increases? Anyone running a Bully Dog box see better mileage? What are the theories about how this occurs? Better atomization of fule w/ higher pressure? Local dealer has a Torque Dog fom a customer that took it off his '03. He had bad vibration in front end and sold truck. He's asking $550 for it. I think that's high, but haven't really checked pricing yet. Any advise is appreciated.



RandyN

 

[MUDDY]

Originally posted by randyn

MPG increases? Anyone running a Bully Dog box see better mileage? What are the theories about how this occurs? Better atomization of fule w/ higher pressure? Local dealer has a Torque Dog fom a customer that took it off his '03. He had bad vibration in front end and sold truck. He's asking $550 for it. I think that's high, but haven't really checked pricing yet. Any advise is appreciated.



RandyN

ive seen an increase in mpg on mid position



550 is decent buy IF it is the adjustable box. retail is 749

 

[RCrowley]

I have seen an increase of 1-2 miles per gallon and that is calculating it by hand. I pulled a load of hay about 200 miles yesterday the whole rig grossed out at just over 26,000, don't tell the d. o. t. I had the box on medium and still got 13mpg. I cant believe how well this thing pulled that much weight

 

[dieselpilot1969]

well been a week now and still no response from bully dog