EFILive tuned Cummins hits 5,300 RPM

[GMPX]

It's finally happened, after years of Cummins owners being told it can't be done, the RPM limitation on the 5.9L Cummins ECM has been beaten. We did say EFILive would change Cummins tuning forever, well, here's more proof.

Firstly, EFILive wishes to thank Brayden from Fleece Performance for he's persistence in working with us on beating this problem. When we first hinted at doing Cummins tuning Brayden said to me that he will do anything to help us figure out how to beat the RPM limiter. As he had a test truck with all the right parts as a mule there was nothing stopping us when the time came to give it a go.
With the time zone differences between Australia and Indiana, Brayden often found himself at he's workshop at 1am, 2am, testing changes we'd make over here during our working hours. Well finally we did it, and at some insane hour of the morning in Indiana you may have heard their shop truck screaming to 5,300 RPM.

It's not a 100% perfect run, the injection is maintaining over 100mm3 of fuel up to about 4,200 RPM, but starts to taper off above that, still, this is a minor set back we will keep pursuing and it may be something as simple as another table that was never calibrated from factory to fuel that high.

This RPM Limiter fix will not be available in our first public release, but it will at some point be available for everyone.

Below is a screen shot of the scantool from the 5,300 run and another video showing it's real (apart from the stupid Tach not working that high!).

Thanks,
Ross

[Boost]

Congrats, very proud of EFILive again as usual! Maybe they can keep up just enough to read the license plate on the Duramax now...

[x MadMAX DIESEL]

awesome

[Brayden]

I just hit 55xx and the converter bolts loosened up... Sounds a lot like a rod bearing! It's fixed and ready to head to Bowling Green.

[FUBAR]

Great work fellers!

[schwoch1]

WOW!!!! I didn't even know that an engine with a 4.72 inch stroke could hit 5300 RPM more than once!!! ALmost makes me want to sell my '99 Cummins Ram for a newer one......well maybe not!!! So when does the '98 - '02 VP44 support come about ...... Just kidding!!!
Keep up the good work!!!

Mike

[joecar]

Wow, 4.72" stroke...! What is the connecting rod length...?

[schwoch1]

Wow, 4.72" stroke...! What is the connecting rod length...?

After a quick google search, I came up with 7.545" center to center......... considering your average 350 Chevrolet has a 5.7" rod, that's damn long!!!!

Mike

[joecar]

Piston acceleration is green graph.

Cummins
5300 rpm -> 555 rad/s
BDC: +1.6618[in/rad^2] *555^2[rad/s]^2 /12[in/ft] /32[ft/s^2] = +1333 g
TDC: -3.0918[in/rad^2] *555^2[rad/s]^2 /12[in/ft] /32[ft/s^2] = -2480 g

LS1
6000 rpm -> 628 rad/s
BDC: +1.2728[in/rad^2] *628^2[rad/s]^2 /12[in/ft] /32[ft/s^2] = +1307 g
TDC: -2.3467[in/rad^2] *628^2[rad/s]^2 /12[in/ft] /32[ft/s^2] = -2410 g

At 5300 rpm the Cummins g forces on the piston are comparable to the LS1 at 6000 rpm.


Note:
these graphs are wrt crank angle, i.e. due to crank/rod geometry, i.e. regardless of any rpm;
to get velocity and acceleration wrt time, multiply by radian/s and (radian/s)^2 respectively.

Convert rpm into radian/s like this: 2*pi*(rpm/60)

[joecar]

It has higher piston velocity (which depends mostly on stroke) than the LS1, you can see it in the graphs.

Piston velocity is blue graph.

Cummins:
2.5[in/rad] *555[rad/s] /12[in/ft] *60[s/min] = 6937.5 ft/min (peak)

LS1:
1.9[in/rad] *628[rad/s] /12[in/ft] *60[s/min] = 5966.0 ft/min (peak)