What makes a truck do this?

[Light It Up]

Ive heard trucks and tractors sound like this for a couple years now and it may be a dumb question I should know but what makes this truck lope before take off is this video?

 

[apocalypse1812]

what video?

 

[Light It Up]

Sorry
http://www.youtube.com/watch?v=72H-hGj6fHw&feature=fvw

 

[Light It Up]

Im guessing its just a sh*t ton of fuel and big lines?

 

[ride42]

Probably a real big cam...

 

[JFlagg]

Probably a real big cam...

:hehe:

 

[dmigz57]

Im guessing its just a sh*t ton of fuel and big lines?

yea lots of fuel most likely running an ag governor as well

 

[sk31821]

The biggest reason is because while spooling up the rack in the injection pump is boucing back and forth befor going to full fuel.

 

[ride42]

:hehe:

 

[BluegrassDiesel]

Governor bounce.

 

[dieselbeef]

probly the blonde at the beginning of the video

 

[Light It Up]

Governor bounce.

For what reason does the governor bounce?

 

[Scooter's Roofing]

springs

 

[quarterman]

Its called a sigma pump

 

[Extended Power]

Simple.....Very High Horsepower...

 

[Farmallgray]

I'm not 100% sure this is correct but I think when the governor is modified for high rpms by using stronger springs and/or lighter weights, they can't counter-balance each other properly at lower rpms. So the springs and weights are kind of playing tug of war with the rack.

 

[Timebomb]

Its a combination of pump cam profile, timing, and gov springs

 

[ride42]

I did say cam...

 

[Santa Gertrudis]

Hey my arm is in that video! LOL

 

[SCHOOL BUS]

i like the noise at the end better!