please explain the pros and cons of 1stvs 2nd generation 12v cummins

bears4x4

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I'm at that point, my 7.3 decided to die, so I was looking in to doing a cummins swap but which one, common rail? , 1st or 2nd gen 5.9, I don't really know the differences, could some one explain them for me
 

argve

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1st gen cummins - uses mechanical rotary pump - can be made to make decent power for little money. Fuel mileage is decent. Early ones did not have the intercooler I can't remember the first year for the intercooled dodges.

Everything below was intercooled from the get go.

2nd gen cummins - uses mechanical inline pump - often referred to as a P-Pump. Can be made to make insane power for little money. typically these are known for the best MPG.

Both of these engine share a lot of parts and there really isn't much difference between then other than the fuel system.

Both of these only need one wire to run = fuel shut off solenoid power.

The 2nd gen also has the 24V engines which started in late 98. These require the use of a ECM to control the rotary pump VP44. These can be made to make decent or insane power but costs a bit more money to do it because you have to actually purchase all the items to increase their power. But this brings on the ability to at the flip of a switch or press of a button increase the power setting or lower them. These typically get decent mileage. This engine still has mechanical injectors. The VP44 has gotten quite the bad name because they tend to fail in stock form. I have heard a lot of reasons why but the one that seems to come up a lot is that because the pump is lubed and cooled by the fuel that if your supply pressure or volume drops then it's pretty much downhill from there.

Next in line is the Common rail fuel system. In this application they feed fuel to all the injectors at all times then open the injectors electrically to control the fuel. These are typically the quietest of all the Cummins engines in that they don't rattle as much. That was a big selling point for them. Again this engine will require the use of an ECM to control it. Fuel mileage is decent and again just like with the VP44 series engines you can have anything from decent to insane power levels. but it costs money.

Now they have 6.7l which I don't know alot about other than it's computer controlled and seems to be proving out to be as reliable as all the previous engines.
 

argve

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If I was to do motor swap some day I would swap in a either a 1st or 2nd gen 12 valve engine. I would not do a computer controlled one because I don't want to mess with that type of stuff. The mechanically injected ones are far more straight forward swap. Not to say that a swap is easy but you know what I mean.
 

bears4x4

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What years am I looking at for a 2nd gen cummins, what would a 92 year be? What kind of decent mileage am I looking at getting
 

argve

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First gens stopped in 1993

1994 was the first year for the 2nd gen.

Did forget to add that there were 3 different hp ratings on the 2nd gen pumps.

180 in auto trans trucks
195 in early manual trans
215 in later manual trans

Fuel mileage... A lot depends on your right foot, drivetrain set and gear ratio... With my goat truck I would get 20-22 on a real consistant basis. She had a 5 speed manual tranny with 3.54 rear gears. I could eek out 24 on the highway running 70+ . Lowest I would normally see would be 20 in the winter (I like to let it warm up) I would not avoid rolling smoke and would still get those numbers - I rolled coal at least once a day and didn't drive like a grandma either, but I wasn't launching either from every stop light but would accel with traffic and would shove down on her a little to pass someone. You know normal driving but there were days that I would roll the rears in smoke and on those tanks I would see a drop of about 2mpg.

I had a 195hp rated pump.

Now with doing the swap keep in mind that these engines stock will hit the gov at 2400 ish (if I remember correctly) so you might want to look into changing your rear gear ratio out and installing a govenor spring kit to increase the max rpm to 3k.

If and when I do a convert I will just use the dodge tranny (NV4500) and will swap out my rear gear ratio in order to have the fuel econ and be able to run over 100mph when needed.
 

u2slow

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I'd suggest a 94-98 Dodge for a swap.... the intercooler and P-pump gives you more jam than the 1st gens. Moreover, you can use the complete NV4500 and the Dodge t-case.


That said, the 1st gens - especially the early non-intercooled ones, makes for an easier swap. At 160hp rated, they are also very thrifty. Probably only need to fill mine up once a month!
 

rebel_horseman

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1st gen cummins - uses mechanical rotary pump - can be made to make decent power for little money. Fuel mileage is decent. Early ones did not have the intercooler I can't remember the first year for the intercooled dodges.

The '89-91 engines were non-inter-cooled. The 91.5 trucks were inter-cooled and remained this way until the end of the '93 model year when the 2nd Gen was introduced. The IC trucks (and the 2nd Gen trucks) were not completely wire-free in that they did require a small ECM to control alternator charging and ABS functions. This can be easily remedied by swapping to an external voltage regulator to control the alternator.

The main difference between the VE and P-pump trucks is the fueling characteristics. The VE is designed to deliver lots of fuel at low-RPM thereby producing mountains of torque. The P-pump tended to give similar fueling on the lower end while delivering more fuel on the top end. This is why you see more torque for the 1st Gen for the same HP rating compared to the P-pump trucks. Both pumps were governor-limited to 2600 in stock form those they can both be easily made to run to 3200 or more with a governor spring swap.

The VE's power increase is easily attained with the turn of a screwdriver whereas the P-pump requires a different fuel plate (or grinding the stock one). Both do well with injector upgrades, however the heads are different from one generation to the next so injectors are not necessarily universal. Also, the non-IC engines are different from IC and have larger injectors.

The IC on the 1st Gen trucks was decent but undersized so if you're doing a swap you might as well look for a used 7.3 'Stroke inter-cooler for more capacity.
 

bears4x4

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Ok I'm back, I found a " 94,95 " cummins, running on a stand, what do I look for to confirm that its a 94-95 cummins, I know power strokes not cummins
 

rebel_horseman

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There is a metal tag from Cummins on the driver's side of the engine. It will have the build date, HP rating, QPL number, engine ID number, etc. That's a good start. The HP rating will determine if it's an auto or manual engine.
 

bears4x4

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Sweet info, what I ment by does it matter if it was an auto or standard, will either engine bolt up with the adapter plate to my 4r100?, is there any noise, sound , play in parts that I should look for? If all goes well ill be buying the conversion parts from fordcummins.com
 

bears4x4

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Ok, decision. Point, came across 2 94-95 cummins, one "rebuilt" 2000.00. Don't have paper work on it but its a running engine on a stand no ps pump intake tubing etc, then another engine in a truck, 130 k complete running will let me have it for 2500 complete engine only, intake, down pipe etc. What to do, what to do? Opinions please?
 

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