Db2831 mods internal

Redblock

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I’ve got a few performance questions for a hot street truck.
Ill attach some pics of the pump ID.

Quick history story, i have a built 6.2 and I did the following to the 2831-4911 pump :
1. Removed leaf spring
2. 3/8 inlet
3. Shaved off about 1/4-1/3 of the gov weights, evenly on all of them.
4. 6.2 gov spring assembly, nut shaved down and rod maxxed out. Also added about 1/4” to the end of the rod pushing on the hobo.

I have very little experience doing these mods on these pumps, so I am just shooting in the dark. I get the theory of operation, but not a ton of experience. Anyway, it did not really do as much as I had hoped. It did fuel more, still not enough, but the fuel response and rpm still aren’t enough. Guessing its only turning 4000-4200 or so, and it just kind of runs up and flattens out.
Why did my old raggedy n/a 6.2 rev up and ba-ba-ba-ba at the top end, where this one just runs up and flattens out smoothly? Just curious about WHY the difference.
Hard to tell alot of performance “gains” because that engine is in a heavy lifted square body.

Now to the point..

The new truck is a square body shortbed stepside, lowered, also a built motor. I have this other pump, i have pulled 3 gov weights (every other), removed the leaf, 3/8” inlet, 6.2 gov spring, shaved nut.

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I havent put it back togather completely just in case there is more “I” can do.

Can any gains be made from the smaller gov spring? Adjusting, bending, etc?
Removing the metal tab where the idle spring contacts?
How about machining a couple thousands more on the metering valve? Or somehow getting it to turn further?
What about the advance piston/linkage mods? Add/remove material to the cam/ramp?
What about static timing setting for performance?

Mainly looking for quicker revs, less “governing”, more fuel, and more rpm.
Dont really want it not reliable, but i do understand it may induce some quirks.
I am saving for the big pump from CCD, but in the meantime i am trying to real world learn “if you change this, it does this” type thing.

Engines i have covered, but pump wise…..clearly I know enough to be dangerous lol.
 

mike k

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Redblock for cdd he put a stronger transfer pressure spring in and that would fill his charge ports more and with higher pressure fuel you could try that it will give you more fueling in the top end of thw rev range not so much down low but be careful how stiff you make it cause to much pressure and the ip body will start to flex you guys also have marine db4 pumps you could mod one of them as well.......
 
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