Reman VP44's
 

Is there a difference in VP44 pumps for the standard 24v vs the HO motors? or auto vs manual?

Yes there is, but I don't know the differences.

Auto and 5sp is standard output. 6sp is high output. The only difference in them as far as I know is the onboard electronics.

the SO Vp44 runs all autos and 5speed manuals. the HO VP44 runs the 6 speeds trucks. The electronics are different on the two pumps. You can NOT run a HO VP44 on a SO engine because of the way the injectors are set up. You can do what I did I swapped my HO pump for a SO PUMP becase HO pump limits you to 500hp and less. The SO pump not responds beter to electronics but supports fueling well past 750hp.

The H.o will build over 500. Ive seen me do it alot. The S.O pump in most cases will build better top end power IMO but loose alittle on the bottom. The Electronics are the main difference but there are some internal differences as well.

Arnt the HO pumps high pressure and low volume and the SO low pressure and high volume?

Yes :tu:

The HO pumps have smaller plungers thus creating higher pressure and lower volume, where as the SO pumps have larger plungers creating lower pressure and higher volume. This and electronics are the only differences, far as I know injectors are the same for either pump.

exactly, we talked about this a few weeks ago. so for more power it seems that the so pump would be better because of higher fuel volume allowance i would think