Engine/Transmission (1998.5 - 2002) Difference between VP44 on 2001 H.O. vs. 235hp

[NicholasMiller]

Is there a difference between the VP44 on the 2001 HO motor and the 235 hp motor? I just had my 3rd VP44 (covered under shop warranty) and it seems like the truck is not making as much hp as on the previous pumps? :{

 

[Diesel_5.9L]

Not that I am aware of most of the difference in the engines is beefed up pistons, gallery cooled pistons and software adjustments. There is a pretty cool website from Cummins that pretty much tell you most everything you need to know about their dodge Cummins engine. # 29 on the list addresses the difference between standard and H. O. engines. http://www.cummins.com/na/pages/en/products/dodgeram/faq/index.cfm

P. S. How is the lift pump pressure

 

[RustyJC]

The HO (ETH) pump has smaller bores but operates at higher pressure than the SO (ETC) pump. The injectors differ as well - the HO injectors have a smaller flow area but a higher operating pressure than the SO injectors.



From the DodgeRam website:

What's new in the ETH engine:



Electronic Controls: New ECM calibration and fueling algorithms.

Fuel Pump: Increased fuel flow in the Bosch VP44 injection pump.

Injectors: Designed to provide increased fuel flow.

Injector note posted to the TDRoundtable by tgbol:

ETH injectors (3946306) flow 600cc at 100bars for 30 seconds

ETC injectors (3944828) flow 640cc at the same test.

Turbocharger: Revised wastegate setting for 26psi at the turbocharger outlet.

Manifold boost specification is 43. 5 inches Hg / 21 psi

Head: Valve seat inserts for added durability.

Pistons: New pistons with higher 17:1 compression ratio.

Flywheel: New flywheel with 330 mm diameter clutch (vs. std. 310 mm).

Rusty

 

[NicholasMiller]

Diesel, my fuel pressure is 15. 5 at idle and 12-14 wot and has been in that range for the life of the previous VP. Rusty, I assume that there will be different model numbers for the pumps so looks like I need to look up and compare them.

 

[NicholasMiller]

Thanks for the information. I copied (actually used a digital camera) down the numbers (several different sets, one from the bar code sticker another that was stamped on the casing of the pump, turns out the stamped number is the Cummings #) and called another local injection pump service shop. Sure enough, I have the low output pump from the ETC engine. Now have to deal with the shop that did the work.

 

[SSabick]

WOW!!! So the low output pump actually does work? That means you can hook up a timing box, and get better response than your old HO pump would have responded. That would also mean that you are loosing just a bit of fueling, but wouldn't the timing make up for the slight fuel loss? Aren't the Dyno guys doing better with the SO pumps over the HO pumps?