Engine/Transmission (1998.5 - 2002) SO and HO pumps...

[sparks57]

They are designated as -027 and -028 right?



What is the difference? I've heard the SO pump can actually outflow the HO pump?



Is the HO beefier? Does it maybe last a little longer?



Please explain!

 

[Tcolesanti]

027 is the SO pump. The 028 pump is the HO pump. They are not interchangeable. I don't believe either is beefier or lasts any longer than the other. FWIW, when I talked to Cummins they said Bosch was introducing a new pump with teflon coating I take it on the inside of the plunger cylinders of the pump.

 

[SpicyJam]

The H. O. pump delivers less fuel than the other. That is why no matter what electronic box you tap your wire with the H. O. can only achieve around 95hp. That is why I am going to a P-pump, to rid myself of the electric B. S. and to be able to adjust my timing the way I want it.

 

[Jim Fulmer]

Why not go to the high output pump? I like P-Pumps too but I sure like being able to play with the pump from inside the cab!



Jim

 

[SpicyJam]

Jim, ya I can get a higher flowing pump to work on my truck, problem is that I can not get away from the extra timing the ETH puts out, so I would still not achieve the power a ETC can.

 

[sparks57]

I'd love to run a P7100, but the cost does not justify the ends... IMO.



For a while there, I was really thinking about ultimately ending up with the P7100, but I just don't think I'm aiming for it any more.



Better VP44's are in the works, from what I've heard... just hang on!



BTW: is anyone producing upgraded VP44's yet? Any that are beefed up or flow more?