Timing on '05 (sensor ?s)

[rbattelle]

Nothing in life is free. What is being lost with the advanced timing?



-Ryan

 

[Matt400]

Increased Nox

 

[SHobbs]

Any hope for the 2nd gens to get one of these, or is it possible?

 

[67guzzler]

Increased Nox

Yup -- And if someone feels bad about that, they can use a additive like PowerService DieselKleen to offset the NOx emissions.

 

[rbattelle]

Increased Nox

So you're saying the only reason Cummins set the timing where they did was for emissions?



If that's true, I might just have to invest in one of these. But I'm reluctant until I can be certain that increased NOx is the only side-effect...



-Ryan

 

[67guzzler]

Ryan -- not to persuade you or anything but I'm SUPER conservative and I ordered one. My understanding is that it advances the timing the same way a box / downloader would but without the investment. It's easy to put on and take off and it's a mild timing advance. As you know there are 3 injection pulses per cycle. By advancing the the timing of the injections it will bring in the 3rd pulse for emissions in earlier and be used for more for power and less for burning off material in the exhaust manifold. This along with advancing the earlier pulses explains the MPG and power increases. Based upon what I've read, I doubt that this mod could hurt anything. Just my $. 02.

 

[rbattelle]

As you know there are 3 injection pulses per cycle.

Mine's an '03... I only have 2 pulses.



Please excuse my skepticism... I'm just leery of things like this because I generally think "Cummins knows best". That might be a bit naive, but I'm not an automotive engineer and I don't have all the facts that went into the design of the control system for the B5. 9.



Just how much is it changing the timing? I thought I read something like 2 degrees...



However, if you guys are right and the decision to time the engine where it is was based entirely on emissions, then I would have absolutely no problems buying one and using it.



Maybe I could email the Powermaster about it, except I'm not sure they'd understand the question.



I'm also a little confused by the Rokk website. They say they make industrial blowers, but their only products are for our Cummins engines... am I missing something?



-Ryan

 

[67guzzler]

However, if you guys are right and the decision to time the engine where it is was based entirely on emissions, then I would have absolutely no problems buying one and using it.

I'm not conceeding anything but what if we're wrong? Advancing the timing is one of the things that most of the boxes / downloaders do. It's really one of the more benign things. People with pyrometers are reporting cooler EGT's with the pulses coming in earlier. It's a more complete burn too.



C'mon Ryan. Experiment a little. It's under $100 and it's not going to break anything -- right away! Have some fun!



P. S. It's not like that honeycomb air thingie that straightens out the airflow so your turbo will be more efficient.

 

[rbattelle]

I'm not conceeding anything but what if we're wrong? Advancing the timing is one of the things that most of the boxes / downloaders do. It's really one of the more benign things.

I know, but I live by the belief that nothing is free. There is a specific, concrete reason the stock timing is where it is. You know if Cummins could improve fuel economy by 1 mpg just by changing the timing they absolutely would. So what stopped them from doing it? If it's emissions, I'll place my order for the sensor tomorrow. If it's something else...



Maybe I have too much faith in Cummins.



-Ryan

 

[Bob4x4]

Any hope for the 2nd gens to get one of these, or is it possible?

No luck. The crank sensor on the 2nd gen fits into a hole bored into the side of the block. Buy a box and get it all,fuel and timing



Bob

 

[67guzzler]

I know, but I live by the belief that nothing is free. There is a specific, concrete reason the stock timing is where it is. You know if Cummins could improve fuel economy by 1 mpg just by changing the timing they absolutely would. So what stopped them from doing it? If it's emissions, I'll place my order for the sensor tomorrow. If it's something else...



Maybe I have too much faith in Cummins.



-Ryan

RYAN! HAVE SOME FUN!​

It's $78 delivered. It won't break your truck. I promise. I'll buy you a new one (truck!) if it it does. I swear!



Now go to that www.rokktech.com site and geeeetcha one.



Joking aside -- Seriously. They retarded the timing and added the 3rd pulse for emissions purposes. They also have really high egt's to burn off emissions via the 3rd pulse in our 2004+ model year trucks. That's a major reason why people with 2002's on back are getting such better economy than the CR models. They have their timing more advanced.

 

[Matt400]

So you're saying the only reason Cummins set the timing where they did was for emissions?

I think so Ryan. If Nox was not an issue they would be free to run it more advanced taking advantage of the added fuel economy and performance. Retarding injection timing is a major player in reducing Nox and engineers are taking advantage with simple software changes to find a middle of the road setting.



Ted Jannetty a respected name in Diesel Performance wrote:

For the 24 valve engines of today if all you did was advance the timing map equally across the board, you would see a increase in power and mileage, in the range of 5% to 10%. But as you add more and more fuel and boost the timing requirements change, specifically for each combo.

I found some good reading on injection timing here:

http://dodgeram.org/tech/dsl/FAQ/timing.htm



There is a great chart at that link giving the trade offs you questioned.

This particular mod is said to be 2 degrees which isn't much at all considering the TST box will add as much as 10. It would most likely push Nox above where CARB wants it but dang. . imagine what TST or Juice pushes it to.

 

[nickleinonen]

and if you want to do this mod on the real cheap, just mod the tone wheel dowel hole to allow you to rotate it instead of moving the sensor...

 

[Matt400]

Thanks Nick, I am going to take a look at that. have you done it?

 

[67guzzler]

and if you want to do this mod on the real cheap, just mod the tone wheel dowel hole to allow you to rotate it instead of moving the sensor...

Nick -- Isn't this permanent?



Can you please snap some digital pics of the process so we can see what you mean?



Thanks!

 

[barbwire]

I bought one. Easiest bomb I've ever done with the most benefit. I gained 1 mpg towing, with snappier throttle response on the lower end. Truck seams to be happier. So far, I am happier. BTW, rokktech puts a lifetime guarentee on it. I put on about 1300 miles with it installed, and rough guess is that I used possibly 8 to 10 gal. less fuel than I normally would have on the same trip. You do the math. But,I would have to say, that, (at todays fuel prices), it is well on it's way to paying for itself. JMO

 

[Matt400]

I could see the tone wheel being less expensive but allot more work getting to it.

 

[67guzzler]

I found some good reading on injection timing here:

http://dodgeram.org/tech/dsl/FAQ/timing.htm

Matt -- I just read the info at that link.



I really liked the table and the explanations... Ties together for me a lot of what people have been saying.



Thanks!

 

[rbattelle]

Okay, I think I've got my brain wrapped around just exactly what's going on in the cylinder when we advance the timing. Believe I understand now what the tradeoffs are. There is only 1 tradeoff that "bothers" me a little: peak cylinder pressure is going to increase with advanced timing [this is probably what manifests as improved economy and power, as MEP would increase].



So the question is, how much are we eating into the design margins on the engine by raising cylinder pressures? Probably not enough to make any difference in an otherwise stock engine. What about the sensitive injector tips? Could their lifespan be shortened by seeing more average pressure over time? Don't know.



I may be coming around... especially since JGann offered to buy me a new truck if mine explodes! [i think i just heard what sounded like a big explosion out in my driveway... hmmmm]

 

[fbaurley]

Ive been looking into the sensors, myself. I was just wondering if anyone has an experience with it , and mileage gains etc on the 305/ 555 engine. Id no doubt buy it if i had the 325 /600/610. Ts there as big as gain potential on the 305?