3200 RPM Governor Spring
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3200 RPM Governor Spring
After cruising the site I saw some comments that said I could up my rpm's with a 3200 rpm spring and by grinding off something in the fuel pump. Anyone know where to get the 3200 rmp governor spring? Exactly what is it that you grind off in the fuel pump when you put the governor spring in? Any info would be greatly appreciated. Thanks!
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From: Golden, Colorado
Piers Diesel Research, They are a website/store/repair shop I believe.
Good place to shop.
http://www.piersdiesel.com/
Good place to shop.
http://www.piersdiesel.com/
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Adminstrator-ess
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From: New Holland, PA
The AFC lever is circled in yellow. The red line points to the "foot" that gets ground off. Mine is ground so that the area where the foot was is now in line with the rest of the lever.
Just to clarify where to grind, you want to grind the surface (the back of the lever as it sits with the pump assembled) that the red line is pointing at, not the bottom of the lever.
Just to clarify where to grind, you want to grind the surface (the back of the lever as it sits with the pump assembled) that the red line is pointing at, not the bottom of the lever.
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From: Katy, TX off north Mason Road.
Originally posted by mhuppertz
I put in the 3,200 a while back, but didn't know about grinding the AFC lever foot. What does this do? Is it worth taking the top back off my pump?
Mark
I put in the 3,200 a while back, but didn't know about grinding the AFC lever foot. What does this do? Is it worth taking the top back off my pump?
Mark
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Joined: Mar 2003
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From: New Holland, PA
http://dens-site.net/Dodge_CTD/Gover..._Spring_24.jpg
A much better pic of the "foot". Thanks Den!
From an earlier post of mine:
A simplified version:
Grinding off the foot is worth somewhere around 30 HP, and the torque that comes with that much extra HP. 
A much better pic of the "foot". Thanks Den!
From an earlier post of mine:
I like the AFC lever mod better than turning the pump up to the edge of runaway. The reason the pump wants to run away is that you bias the control collar so far toward the "full fuel" position that there is no longer enough open port area in the "defuel" position to slow the engine down at high RPM due to internal pump pressure. If you're sitting there going "WTH does that mean?" you're not alone. Read on.
VE pump 101: The control collar controls injection duration (which controls the amount of fuel injected) by varying the amount of effective stroke the injection plunger has. The control collar covers a vent port in the plunger during the effective part of the stroke, as the plunger moves towards the back of the pump the vent port is uncovered, which bleeds off the pressure and stops injection. The longer the vent port is covered by the control collar, the more fuel the injectors get. The control collar position is determined by the governor and the governor spring. Basically, if you are asking for more RPM than the pump is making, the collar is pulled towards the full fuel position by the governor spring. Once the pump is making the RPM you have asked for, the governor balances against the governor spring and brings the control collar back towards the defuel position.
Cranking up the fuel screw moves the entire governor lever assembly but does not change the range of motion. When the fuel screw is too far in, there is no longer enough open port area in the new "defuel" position, flow is restricted so injection continues and engine RPM hangs or continues to rise. The shutoff lever will not help you here because it acts on the governor lever - which is already defueling as much as it can.
Modifying the AFC lever increases the travel of the governor lever towards full fuel but does not move the defuel position. So instead of moving the range of motion, you increase the range of motion in the full fuel direction. Clear as mud?
VE pump 101: The control collar controls injection duration (which controls the amount of fuel injected) by varying the amount of effective stroke the injection plunger has. The control collar covers a vent port in the plunger during the effective part of the stroke, as the plunger moves towards the back of the pump the vent port is uncovered, which bleeds off the pressure and stops injection. The longer the vent port is covered by the control collar, the more fuel the injectors get. The control collar position is determined by the governor and the governor spring. Basically, if you are asking for more RPM than the pump is making, the collar is pulled towards the full fuel position by the governor spring. Once the pump is making the RPM you have asked for, the governor balances against the governor spring and brings the control collar back towards the defuel position.
Cranking up the fuel screw moves the entire governor lever assembly but does not change the range of motion. When the fuel screw is too far in, there is no longer enough open port area in the new "defuel" position, flow is restricted so injection continues and engine RPM hangs or continues to rise. The shutoff lever will not help you here because it acts on the governor lever - which is already defueling as much as it can.
Modifying the AFC lever increases the travel of the governor lever towards full fuel but does not move the defuel position. So instead of moving the range of motion, you increase the range of motion in the full fuel direction. Clear as mud?
Grinding the foot off the AFC lever increases the total travel of the governor lever. This allows you to make more power without turning the pump up and the problems that go along with it like runaways and not being able to get the idle slowed down. Turning the pump up only moves the governor arm further towards the full fuel position, it does not increase the range of motion. This is why you eventually reach the point of runaway if you keep turning the full fuel screw. The only time I would recommend NOT grinding the foot during a 3200 RPM spring install is if you live in a state where the truck has to pass a "snap test" for opacity.