Engine/Transmission (1994 - 1998) Ideal timing for 2100 RPM?

[mschoenheider]

As far as I understand, the timing of our injection pump does not change with RPM. My question is what would be the ideal timing setting (most power, best economy) if you were to run all day long at about 2100 rpm?

Mark

 

[Jim Fulmer]

Still falls back on 15. 5 to 16. 0 as the best overall setting, lots of timing and towing down do well together.



Jim

 

[JJW_ND]

15 - 17 degrees

I have a somewhat similar setup. I just got back from Muncie and did the best MPG I have ever done for a longer trip. I have every drop of fuel logged (use to hotshot) over the 230K miles I have. I have gotten better then 22 before for short trips only to be followed up by a lower tank or preceded by a lower tank.



I am sure the lower compression I am running did not help my mpg. I am sure the amalagated additive can not take credit for all the increase. Timing is the only other magor change!



I use to expect 18 - 20 mpg running 2000 rpms and 68 - 70 mph. Very repeatable given decent weather.



I got 21. 5 for the entire 2400 mile round trip to Muncie and back. best tank (I carry a total of 80 gallons) was 22. 5.



My timing is based on the signal pickup near the pump so it is really around 17 or 18 degrees.



It sure runs good, quiet, and great mpg!



jjw

ND

 

[mschoenheider]

I guess I was looking for something more technical. I have read in the forums that advancing timing to 16 degrees BTDC helps out with high RPM operation. In my mind that makes sense that the fuel would need to be introduced earlier in the cycle to have enough time to burn with the engine at higher RPMss. It also makes sense that at each RPM level, there is some ideal value for injection timing. I guess my question should have been stated as what is the perfect timing for the most efficient burn of fuel, at 2100 RPM engine speed? I know there are number crunchers out there, lets hear from you!

Mark

 

[Futures1]

Customer Service;

Hey Mark; certainly a controversial subject,

as you may see in the next 24 hours )

I have had good results by contacting the guys who build these engines. You can direct your questions through "Customer Service" in their site. Best i could find was to go no more than about 1 degree advanced from the timing shown on the engine plate. But I did not ask for a specific RPM.

http://www.cummins.com/na/pages/en/index.cfm



Hope this helps, Dick S.

 

[illflem]

Problem in getting a good answer to this excellent question is that most research was done to get emissions down with no other factors considered. Seems they would go hand in hand but that's not the case. One to two degrees over the stock recommendation sure gives better fuel economy and a seat of the pants better feeling.

 

[JJW_ND]

What I heard from Cummins!

Not that I am following the advise I heard directly from a Cummins Engineer at the 98 TDR nationals . . . he told me that all 12V used in Dodge applications should be set at 15 degrees at least. They all will see mpg improvements as well as better starting, less smoke.



One degree on on top of all 94, 95 or later auto trucks gets you to about 13. 5 or 14 degrees. While it will help another degree on these would help more.



The later 5sp trucks has a little more advanced timing (13. 5 - 14 ???) that the one degree rule might be more meaningful. The trucks that are at 14 or better from the factory probably run real good already. It is the ones that for some reason or another are at 12 or less that really see big improvements from middle teen timing.



Running higher timing in these trucks is getter about as popular as running non stock fuel plates (TST, etc). As long as it is done with in reason and sensable (not by ear) it is a safe and benificial upgrade.



JMO!



jjw

ND

 

[pathaymond]

No Problem sorry!

I am in agreement with the One over the stock setting or the number on the plate which will allow me to set my time at 15*

I have also sent my pump to a shop to have it calibrated to a uprate of no more than 15% of its stock setting. I have been assured this is the max safe setting for My 180 horse auto engine. I just want to warn others who may be reading and thinking oh this is simple stuff. Like i did. This stuff you read is serious business . The cummins is a fantastic engine so long as its kept within its design limits. This is just my opinion after loosing a engine due to what I feel to be some very incorrect upgrades I trusted others to do. I am busy person and really do not have time to fool with this stuff so I hired it out and now I AM PAYING the price. Buyer beware!

I wish it was proper to bash the entity that raped me!!But I will say watch out South of Atlanta off 285!!He will lie to you and do it to your face with no regard for integrity or morals. His time will come and I would not care to meet my creator carrying his cross!

Heres to ya MR I do hope I have not crossed the line if I have delete me fast!!

 

[Futures1]

Good stuff Pat;

This is taken from Piers Diesel site in the Q&A section. I doubt if "emmision" is their primary concern as might be for the Cummins Company ?? It does seem to back up what Cummins suggests however !!



"Q: How much should I advance my pump timing?

A: For stock trucks or trucks with only mild horsepower increases, the typical rule of thumb is 1° advance is better, 2° advance is not. "



I do agree that there are some who have exception in this area. I see that as somewhat similar to a driver who often exceeds the speed limit in a big way... when everything is just right, something unpleasant will occur

 

[Roger rodbolt]

Re: 15 - 17 degrees

Originally posted by JJW-ND



My timing is based on the signal pickup near the pump so it is really around 17 or 18 degrees.



It sure runs good, quiet, and great mpg!



jjw

ND

JJW,



I'm using my pickup sensor for timing near #1 injector and am interested in the proper place to connect a timing light. I'm told that some engine spec's use the pump end of the line for proper timing and others the injector end and publish timing spec's accordingly. I don't know why that I've not moved the sensor both places to read the difference, but I haven't. Larry

 

[JJW_ND]

about 3 degrees difference

Piers said about 3 degrees difference.



My truck was set at 20 degrees when taking signal from the line nearest the PUMP. I am guessing it is probably more like 17 degrees or so. Next time I am at the shop again I will have my timing checked. Will check both locations.



jjw

ND

 

[Roger rodbolt]

Thanks, I'm going to check the difference in locations too, Larry

 

[pathaymond]

Futures.

I havent forgotten to send you the rest of my story been busy building a engine!!

And trying to work in the rain!!

I got my pump back it seems shop x messed up the pump springs etc as well. What a surprise!!

No offense here but I really think this website needs another look I think there needs to be a place for us guys that do care and appreciate the Integrity the cummins has within its design limits and the other side for the risk takers.

I also have to wonder and please correct me someone if I am wrong. why Cummins or someone from cummins has not spoken up on this site and said whoa Guys this is Ok and this is not I think this whole site needs a disclaimer. I had no clue that you could modify these engines until the Tdr. so I guess I could blame the tdr for my engine destruction. But I am not interested in Blame. But there could be others that might be and are crafty enough to manipulate with a Lawyers help. How Bout it Cummins you built these engines I guess if we dont hear from you it means everything that is speculated and proven here is OK? Isnt there a link to the TDR from the Cummins dodge site?

Pardon my analitical view but I am starting to wonder if I have been helped or hurt by the site. I have gained alot of valuable info and alot of destructive info as well Of course now I know the difference. And of course the site did not turn the wrenches I allowed a supposed diesel performance shop to do this for me. At my request I wanted to remain in safe Cummins specs which I did not know what they were. and I trusted this entity to do so instead They caused in whole or part the destruction of my engine.

trusting I am and in these times we live in thats a nasty enemy!Maybe I just dont fit in at all. But I am stuck here till the boss takes me home.

 

[illflem]

Pat, while a few folks here take the chance and push their engines beyond the design limits the vast majority are either stock or mildly modified. You have to remember the engine as it comes in a Dodge has been detuned in order for the rest of the drivetrain to make it though warranty. Many of us are just restoring the engine to it's design potential as it is when used in other applications such as marine and heavy equipment. When I read of someone chasing the elusive lower egts after several mods my first thought is they have pushed their engine beyond the design parameters and they will eventually have to pay as you are.

My feeling is you timing was probably in the mid twenties either by ignorance or mistake.

 

[Reddog1]

pathaymond - Unfortunately, many of the guys that post on TDR make half truth statements. Many are armchair mechanics, repeat what they think they read.



If I really said what I am thing about these guys, and especially if I could name them, this thread would be closed and I would be thrown off.



You can shut most of them up by asking them directly if they speak from experience or theory.



With that said, and in defense of TDR, you and I cannot be so gullible as to believe every thing we read. We are responsible for our own actions.



If you follow the various guy that post, you will find many are exceptionally knowledgeable, with good info. If you want to go fast, read the go fast guys. If you want reliability, read the reliable guys.



DO NOT FOLLOW BLINDLY.





Wayne

 

[Futures1]

My reply to a new member;

I agree that some information is too loosely

given in the site. . often given without explanation or consideration it seems !! I really feel bad for folks who rely on some of the information they are given in the replys. Like myself, I would expect that a member who has been on the site for some time would understand the new persons position.

Ego has it's place !!



Here is the copy of my reply to a new member who had a question on 05/08/03.

Note my comment after "One of my favorites"

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

"Welcome to you Travis;



You have a great truck there. . I recently purchased a 97 2500 CTD myself and I can tell that it's going to be one of my favorites !!

The TDR site is loaded with great folks and great information... from your description of yourself, I would suggest that you tread lightly. Lots of the members on the site have had a ton of experience with Dodge and the Cummins. So much so, that it is second nature to them !! If you are like me, you need specifics (just as a good carpenter would use a plan when building a house, etc. ) What I think was my best move was to order the Cummins engine manual and Dodge Ram service manual. Now when I get advice from my TDR buddies, I can open the book and see what the "whatsis" is that they were talking about !!

You may receive several good answers for each question you ask !! I like those answers that include the site links. BTW. . there is a wealth of helpful information available in Cummins and Dodge sites as well as in the sites by aftermarket suppliers themselves.



Congratulations to you on your new arrival and

watch out. . these darned trucks are addictive Dick S"

 

[pathaymond]

Bryan

I think you are correct i feel it was a combo of to much fuel with retarded timming I did have alot of black smoke and was told its fine. which caused wash down. I at that time did not trust that entity so I went looking for another opinion. thats when the timming was turned up by another Proffesional! it did clear up the smoke. I think that timming was done by ear!! so I beleive that over the 15K miles I traveled with things not set right and me not knowing they werent due to my ignorance and willingness to trust, that combo is the culprit. You can bet one thing I will not touch or allow anyone to touch my engine again. The bad part about it is I was refered to the entity that did my first upgrades by a known transmission upgrade company!! which tells me there are not alot of checks and balances of referals in place. I refer people in my business alot and I check on my referal and make sure they are worthy of another referal. Oh well Its going to be Ok In another week the truck should be back together and ready to work. I will keep it as a spare vehicle once my new 650 arrives. Thanks for the info that has been shared. Patrick