Engine/Transmission (1994 - 1998) Has anyone changed from a P7100 to a VP44???

[lpearson]

Question? It seems that with the newer style pump that you would get a faster response off the line and better fuel economy (going to electronics instead of manual).



I'm I all wet or what?????



It would be interesting to hear what someone went through and what results came of it.



There are those who swapped out in the reverse, but haven't read of a 12V with a VP44. ---- Interesting thought.



Regards,

Lowell

 

[WadePatton]

All Wet!

While the VP-44 does great for most of us at moderate fueling levels (500 or less). It's just not as durable as a P7100, nor will it flow as much fuel.



Changing injection systems is a very expensive proposition and that's why you see 24's with 7100's and not the other way around. It takes a racing/pulling budget to justify the expense.



Manipulating the fueling curve of a 7100 is all in your hands as well. The fueling parameters of the VP-44 are controlled by the OEM and aftermarket box(es) you hang onto the truck. One is generally limited to on/off and a number of settings between low and high, but that's it. The flexibility and fueling capacity and durability of the 7100 make it THE pump for HIGH horsepower applications.



Note there are plenty of VP's at high power levels too-so you might get mixed input. But until I see software that allows ME to determine the fueling curves for MY application, I stand by the above statements.



flame suit on.

 

[Andy Redmond]

Most of us would not want to do this! The reliability of the electric transfer lift pump and the VP 44 injection pump leaves much to be desired.



Plus you need lots of electronic management features that are not included with the 12v. , 12v. engine block etc. , plus many ports exist on the block (24 valve) for cam position sensors, crank position sensors etc. making a tedious if not impossible conversion.



Fuel mileage is typically better with the P7100 and it is easily "bombed" for more power. Not that it can't become a money pit if you want lots of power.



I would focus on performance uprates that are inline with your fuel mileage goals. Also assuring your stock truck is in top tune, should improve your fuel mileage concerns.



I recently pulled a pump on a 12v auto trans truck that never seemed to perform well and had horrible fuel mileage. When the pump was on the stand the pump tech stated the rack and some other things were "way off. "



Recalibration and improved timing have its owner grinning broadly now, it seems to also get better fuel mileage now too.



I just bring this up to say its a tough ole pump that performs modestly even when out of optimal specs.



Your not wet, you just didn't appreciated your correctly pumped and valved engine! "The fueling is better than the 'greener fuel' of the VP44/24 valve trucks. "



Good luck

 

[onestackdram]

I would like to throw this in as well if I may.



I recently was actually lucky enough to get in touch with a BOSCH rep. and to cut the conv short, and not to give away what the conv was for the most part, I can say this. Bosch themselfes feel this way about the pumps that they offer Cummins for the Dodge applications. The first VE pumps were them figuring out what worked best and while it was a serviceable pump it wasnt their best work, then came the P-Pump and they were greatly enthused (sp?) with it and just kept tweaking her. They were greatly disappointed that Dodge didnt want to continue with it, for they felt they were on the verge of nailing a "monster", but as we all know the EPA and all the other tree huggers screwed auto industry with their regulations. Then we began to talk about the VP pump they are well aware of the problems that have been had by our fellow CTD owners, but were'nt really sure what to do about them because it seemed to be 'just a few' and their seemed to be a something a little different on each one that was bad. So needless to say they weren't real happy themselfs with the product but felt like their hands were tied for the most part. Now onto the new common rail for our '03-'04 friends. From what this 'rep' told me those that work on the 5. 9 cummins engines on the bosch side of things, is this, WOW, they have been greatly impressed and cant wait for all you 'aftermarket' guys to catch up. Their is alot your not finding yet. That is all I can say about that.



Russell

 

[WadePatton]

Originally posted by onestackdram

then came the P-Pump and they were greatly enthused (sp?) with it and just kept tweaking her. They were greatly disappointed that Dodge didnt want to continue with it, for they felt they were on the verge of nailing a "monster"...

Russell

They weren't the only ones greatly disappointed.



While "the bird" (common rail) has great potential and is the way of the future, I'm going to spend the next 10-20 years living in the past--with the old inline beauties. With the exception of my current ride that is. Starting on Dad's 7100 truck for a puller this winter.

 

[lpearson]

Good Info.

Thanks for your thoughts. I guess I'll just dry off now.



What would it take to make my 180 pump into a 215 pump? Would there be a disadvantage? How about fuel milage if I wasn't getting on it all the time?



Thanks,

Lowell

 

[24VChev]

fuel systems

Bring your truck up here and I'll trade you fuel systems . Keep what you got and spend a few bucks on a plate and some gov springs and you will have more power than a 215 pump.







Malcolm

 

[Hammer]

You want to do what????:--) :--) :--) :--) . You haven't bumped your head or anything recently have you????. There is no other combination as reliable as the P7100 and all those wanna be over-valved guys want to convert theirs because of that..... Andy

 

[SEmerson]

I have both a 12 and a 24. Both bombed. AS bombing progressed with them both the 12 would always kill the 24 out of the hole. Now the 12 will out run the 24 all the way around. It is also MUCH more reliable. Also gets better mileage. #ad

 

[wsmalley]

You really need to keep what you got. The P-pump actually is much quicker out of the hole due to the instant response inherent in a mechanical throttle. There is no split second delay while a COMPUTER says how much fuel you can have. Personally I LIKE being able to say EXACTLY how much fuel I want at EXACTLY this a certain time. Now that's just personal preference, but I think many would agree. There is nothing more reliable or power-capable than the wonderful p-pump