Big Bad starter

This starter draws 159 amps @ free spin motor speed 3150 RPM or 700 RPM on the pinion
vs 5.9 starter draws 200 amps free spin @ 3000 motor speed.
Current draw @ max power is 921 amps
vs 5.9 Cranking Current draw 450-700
the big starter will turn the motor @ 57.3 RPM
Its all about load that will determine the amp draw speed.
 
renopker said:
This starter draws 159 amps @ free spin motor speed 3150 RPM or 700 RPM on the pinion
vs 5.9 starter draws 200 amps free spin @ 3000 motor speed.
Current draw @ max power is 921 amps
vs 5.9 Cranking Current draw 450-700
the big starter will turn the motor @ 57.3 RPM
Its all about load that will determine the amp draw speed.
Click to expand...


This is definitely a cool project, not taking that away, but I am saying you will need to upgrade the electrical system on your vehicle, before you really experience the advantages of the larger starter.


Where did you come up with the Free spin data?
Why is there such a wide window on the cranking current on the factory 5.9?

I am sure we will all learn some things from this.

I am just speaking as 20 years ago I worked for a starter manufacturer that provided starters for HD diesels and did quite a bit of work on the testing stations. We had some unique testing situations.
 
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zstroken said:
This is definitely a cool project, not taking that away, but I am saying you will need to upgrade the electrical system on your vehicle, before you really experience the advantages of the larger starter.


Where did you come up with the Free spin data?
Why is there such a wide window on the cranking current on the factory 5.9?

I am sure we will all learn some things from this.

I am just speaking as 20 years ago I worked for a starter manufacturer that provided starters for HD diesels and did quite a bit of work on the testing stations. We had some unique testing situations.
Click to expand...

The data for the 5kw came with the starter (test report and graph ) along with Tq, rpm current draw and voltage. If I have to put larger cables on so be it the interesting thing is the solenoid is the same as the smaller one. I have put a few starters together for custom apps in the past just not a denso.
 
renopker said:
The data for the 5kw came with the starter (test report and graph ) along with Tq, rpm current draw and voltage. If I have to put larger cables on so be it the interesting thing is the solenoid is the same as the smaller one. I have put a few starters together for custom apps in the past just not a denso.
Click to expand...

Do you have a performance chart for the cummins starter? showing the same data?
 
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zstroken said:
Do you have a performance chart for the cummins starter? showing the same data?
Click to expand...

I do not, the data sheet for the big starter is serial # to the starter. The info I have for the 5.9 is from the FSM I have the denso parts books but I haven't found a spec sheet at this point it doesn't matter I got in to this 3 weeks ago and had to wait for the big starter to arrive. The cranking rpm I listed is with 159 tooth fly wheel the fly wheel on a standard 5.9 ram app is 152 tooth when I built my clutch and fly wheel I went to the larger ring gear and moved the starter over it will help in that it gives me more room between the motor and starter.
 
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renopker said:
when I built my clutch and fly wheel I went to the larger ring gear and moved the starter over it will help in that it gives me more room between the motor and starter.
Click to expand...


"when I built my clutch and fly wheel"

Show off, LOL
 
Finished the starter, looks like the only mod to the truck is to open up the cable end and I might have to turn the motor mount bolt around (put it in from the back going forward).
DSC01651_zpstw2qa19w.jpg

I will install when I get some time.
 
2/0 Gauge (1127) cable and Quickcable Fusion solder walled lugs for the starter wire will eliminate issues regarding voltage drop. (As stated above, you'll need to open up the lug for the starter stud even on a stock starter) Use Military style battery terminal clamps so you never need to take them off the battery & easily add accessories.
 
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I'm going to change the cables as my time allows the OEM cable Battery to starter is 2/0 and the battery cross cable is 1/0 I'm putting 3/0 on it.
 
Sweet project, I would have been curious how much of a performance increase just changing the cables out would have been.
 
renopker said:
This starter draws 159 amps @ free spin motor speed 3150 RPM or 700 RPM on the pinion
vs 5.9 starter draws 200 amps free spin @ 3000 motor speed.
Current draw @ max power is 921 amps
vs 5.9 Cranking Current draw 450-700
the big starter will turn the motor @ 57.3 RPM
Its all about load that will determine the amp draw speed.
Click to expand...


Curious on what you ended up with engine rpm on the new starter?

Reason I ask is in the data logs of a 3rd gen the starter gets the engine up to about 200 rpm before it lights off.
 
Joesixpack said:
Curious on what you ended up with engine rpm on the new starter?

Reason I ask is in the data logs of a 3rd gen the starter gets the engine up to about 200 rpm before it lights off.
Click to expand...

I think the 57.3 rpm was a miss-figure it spins far faster then it had ever spun.
Ill see if I can shoot it with a lazer. The true test will be in the cold weather as for now Im sure its just close to free load.
 
Awesome. Any info on what you did to modify it? Just mill some of the material off the front to fit the gears in further? Or did you have to modify a flywheel/flexplate?
 
Its not to bad change the drive gear, machine the offset on the nose out to center it. Saw it to shape weld up the offset and where the bolt pattern is, turn the nose to register size
depth drill the bolt pattern and spot face.Nothing to do on the fly wheel.
 
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