Cummins 6CTA8.3 Injection Timing

[74M35A2]

I've got a little bit more than free access. Glad you were able to get the information you were looking for though

Were you able to find anything more definitive or different? Not having an easy way to pressurize fuel to 300-375psi, I'd much rather try to use the dial indicator method, if possible. Can you find any reference to that, in relation to the ESN I provided, or even something generic for the 8.3 with an MW pump?

 

[Wildchild467]

Advancing timing is supposed to reduce EGT, as well as dumping the muffler.

You going to get rid of your muffler??

 

[74M35A2]

You going to get rid of your muffler??

What are you doing in the 5T forum? You've got one of those little boy trucks. Get outta here...

 

[JohnnyBM931A2]

what are you doing in the 5t forum? You've got one of those little boy trucks. Get outta here...

lol

 

[Wildchild467]

What are you doing in the 5T forum? You've got one of those little boy trucks. Get outta here...

Bully!

 

[4XDesign]

I also have free access to Cummins QuickServe (everybody does), and I can't seem to find any useful injection timing info. They talk about IP spill port timing, and they show the dial indicator to measure plunger #1 height ion their tool section of that chapter, but there is no table or chart or how-to for this method. I was expecting to find a timing table of plunger height vs crank degrees. I have not read it in depth though, and have yet to do that. This is easy to find on the internet for a 5.9L with the 7100 pump. My ESN (Engine Serial Number) is: 44455234 (saved within and working with Cummins Quickserve), please try to find timing info beyond what I did if you can.

I bought a full size Volvo road tractor intercooler, same as member 4xdesign did. He did a fabulous job of measuring to find the best fit one, and then installation also. I am copying that. But, I want to install my EGT before I do any mods, so I can accurately report their effect. Advancing timing is supposed to reduce EGT, as well as dumping the muffler.

Have you gotten any EGT numbers? I'm very curious to see how hot these engines get from the factory.

 

[74M35A2]

No, not yet. That is why I am waiting on mods, so I can actually quantify each with an EGT and timed acceleration runs. Hope to have base EGT data by end of this week, but not tonight, as a local member invited like everybody over for free BBQ ribs and beer. So, only fishing stories tonight...

 

[fattboy123456]

Yeah I just took my truck on its first long trip 400 miles Towing a 33' 5th wheel some very steep grades High altitude and flats..
I have the Truck turned up and have a boost and egt guages a 1100 cfm air filter (550 stock) and a muffler delete kit

Total miles 400
used about 1 tank of fuel 55 gallon approx I purchased 72 gallons of fuel but cam home with way more than I left with
33' Fifth wheel right about 8-9k lbs
Saw boost as high as 30 psi
Top speed reached for short period of time 70 mph
and I did my best to keep my egts 1300 and below but this truck had my gauge easy maxed out (1500 deg) so had to down shift
I put 20oz of Radiator fluid in each tire before the trip seemed to help out a lot on the 55 mph shakes (from when i picked it up)
Engine temp never got over 200 deg
Transmission was 185-225 deg
Hit elevation as high as 7000 feet noticed a huge power loss if my math is correct a 21% LOSS

all and all truck did great and was a huge hit at the dunes and in the Parade (sand mountain NV)

Would love to see the changes in getting the timing advanced.........

 

[4XDesign]

Yeah I just took my truck on its first long trip 400 miles Towing a 33' 5th wheel some very steep grades High altitude and flats..
I have the Truck turned up and have a boost and egt guages a 1100 cfm air filter (550 stock) and a muffler delete kit

Total miles 400
used about 1 tank of fuel 55 gallon approx I purchased 72 gallons of fuel but cam home with way more than I left with
33' Fifth wheel right about 8-9k lbs
Saw boost as high as 30 psi
Top speed reached for short period of time 70 mph
and I did my best to keep my egts 1300 and below but this truck had my gauge easy maxed out (1500 deg) so had to down shift
I put 20oz of Radiator fluid in each tire before the trip seemed to help out a lot on the 55 mph shakes (from when i picked it up)
Engine temp never got over 200 deg
Transmission was 185-225 deg
Hit elevation as high as 7000 feet noticed a huge power loss if my math is correct a 21% LOSS

all and all truck did great and was a huge hit at the dunes and in the Parade (sand mountain NV)

Would love to see the changes in getting the timing advanced.........

What kind of filter are you running? I am still pulling filter indicator in the red every time. I'm waiting with anticipation on timing as well!

 

[fattboy123456]

What kind of filter are you running? I am still pulling filter indicator in the red every time. I'm waiting with anticipation on timing as well!

This is not a factory replacement I modified my intake

 

[Rmtaunton]

1500 sounds really high if you just did the rack and low fuel , what else did you do

 

[Jeepsinker]

Well, if it was a multifuel you probably would have melted a piston... but I bet you at least melted some small pockmarks into the piston tops if you hit that temp for more than a couple of seconds.

 

[fattboy123456]

Naw never at 1500 (pre turbo temp) for more than a few seconds i was on that worry gauge a lot!

Muffler Delete
Huge cfm filter as posted previous
and turned the pump up
I could get way way above 1500 deg easy on egts the truck has Sooo much power but I watch that worry meter like a HAWK!
Truck will do 70mph easy unloaded with more peddle still available

Going to starting working on a intercooler and larger turbo/ mabey a twin turbo that hx40 spools up so slow

 

[Rmtaunton]

I've got low fuel screw up 1.5 turns , gov springs out two clicks and the full rack adjusted all the way out , and towing 18k a hundred miles I can't get it to 1300 if I tried bit not any huge hills on that route either.

Question is what did you do to your pump to hit 1500 so easily empty

 

[Jeepsinker]

The intercooler is going to be what makes the biggest difference for you. If you run an HX50, or compound turbo setup, you will likely want to install some good head studs. It may have head studs already, not sure because I've not had a valve cover off of an 8.3 yet, but even if it does, I would upgrade them if you get up around 40 pounds of boost or better, and I'm sure you will.

 

[74M35A2]

6CTA8.3 uses head bolts.

 

[fattboy123456]

I've got low fuel screw up 1.5 turns , gov springs out two clicks and the full rack adjusted all the way out , and towing 18k a hundred miles I can't get it to 1300 if I tried bit not any huge hills on that route either.

Question is what did you do to your pump to hit 1500 so easily empty

My pump is maxed out the gov springs i believe i did 4 clicks the screw is all the way maxed and the star wheel as well

but hitting 1500 on flats is hard thats on a decent grade and it only shoots black smoke when theres no boost on a load

 

[74M35A2]

After much thought and investigation, I think I may be able to advance the injection timing myself, and I want people to check my thinking on this please:

Our 6CTA8.3 engines are timed at 8 degrees per the data tag. This means with both the cam pin (engine @ TDC) and injection pump timing pins pushed in, the advance will be 8 degrees, as that is a function of IP pump setup. But, the IP driven gear is adjustable, as it is a tapered fit like a lawnmower engine flywheel, sans key way, me thinks.

So, question then becometh: If we do the above setup, but then pull the cam timing pin, loosen the IP driven gear, and back the crank up 8 degrees BTDC, and then lock down the IP driven gear there, I think this should give the target 16 degrees of injection timing advance.

Can an anybody see why this would not work? I guess I'm willing to risk my head gasket on it....., but knowledgables please chime in!

 

[fattboy123456]

Wish I could Help this is to new for me please please please do a bad ass wright up and tons of pics

 

[RobertoGatos]

Keeping an eye on this thread to hear what happens.