Best Cummins Engine Swap
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From: Austin, Tx
Best Cummins Engine Swap
I'm wanting to put a Cummins in my big truck (see sig) wasn't sure which one would be the best choice, would like to hear some opinions. I would be running a std instead of the Auto.
1st Gen
2nd Gen
3rd Gen
thanks.
1st Gen
2nd Gen
3rd Gen
thanks.
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From: kingston,wa
1st gen 12v, easy to mod with only mechanical components.
2nd gen 24v, gotta watch for the vp44.
3rd gen, easiest to mod, just plug in or download some electronic wizardry, but have to worry about injectors failing and causing internal damage due to fuel dilution of the oil.
2nd gen 24v, gotta watch for the vp44.
3rd gen, easiest to mod, just plug in or download some electronic wizardry, but have to worry about injectors failing and causing internal damage due to fuel dilution of the oil.
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From: Peoria, IL
Also, the 2nd gen 24v and the 3rd gen engines are electronically controlled. That's not saying you couldn't strip them of the electronics and convert them to mechanical pumps, but it would take a decent amount of work.
The easiest swap would probably be the 1st gen engine, followed by the 2nd gen 12v.
The easiest swap would probably be the 1st gen engine, followed by the 2nd gen 12v.
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From: Baltimore, MD
2nd gen 12v (the ones from 94-98) that use the P7100 pump. only 1 wire to run and its all mechanical.
the 1st gen 89-93 12v were good but the VE pump isnt as capable as a P-pump
24v from 98-02, and the common rails from 03-07 are very complicated and require alot of electronics, and cost more initially
the 1st gen 89-93 12v were good but the VE pump isnt as capable as a P-pump
24v from 98-02, and the common rails from 03-07 are very complicated and require alot of electronics, and cost more initially
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From: Snohomish, WA
The earlier 1st Gen trucks were not intercooled. Although that can be added. As was said, the VE rotary injection pump is not as capable of the power that the P7100 injection pump found in 2nd Gen 12v trucks is.
94-98 2nd Gen 12v trucks are very simple, all mechanical, and easy to turn up.
I wouldn't even bother a 98.5-02 2nd Gen 24v due to the VP44. Seeing how many reports of them failing just out of the blue, they are just too much of a crapshoot for me. And who wants to babysit a fuel pressure gauge?
03-07 3rd Gen 5.9 common rail probably offers the best driveability and ease of tuning for power, but would be a chore to swap in all the electronics necessary for it to run.
For overall simplicity, ease of installation and potential power, I'd say that the ideal donor would be a 12v from a 96-97 truck with a manual transmission. These are the most powerful and refined of the 12v genre. Throw in the very similar 98 12v if you don't mind it's few oddities and quirks.
94-98 2nd Gen 12v trucks are very simple, all mechanical, and easy to turn up.
I wouldn't even bother a 98.5-02 2nd Gen 24v due to the VP44. Seeing how many reports of them failing just out of the blue, they are just too much of a crapshoot for me. And who wants to babysit a fuel pressure gauge?
03-07 3rd Gen 5.9 common rail probably offers the best driveability and ease of tuning for power, but would be a chore to swap in all the electronics necessary for it to run.
For overall simplicity, ease of installation and potential power, I'd say that the ideal donor would be a 12v from a 96-97 truck with a manual transmission. These are the most powerful and refined of the 12v genre. Throw in the very similar 98 12v if you don't mind it's few oddities and quirks.
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From: Caistor Centre, ON, Canada
94-98 2nd Gen 12v trucks are very simple, all mechanical, and easy to turn up.
For overall simplicity, ease of installation and potential power, I'd say that the ideal donor would be a 12v from a 96-97 truck with a manual transmission. These are the most powerful and refined of the 12v genre. Throw in the very similar 98 12v if you don't mind it's few oddities and quirks.
For overall simplicity, ease of installation and potential power, I'd say that the ideal donor would be a 12v from a 96-97 truck with a manual transmission. These are the most powerful and refined of the 12v genre. Throw in the very similar 98 12v if you don't mind it's few oddities and quirks.
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From: Austin, Tx
I love this site, thanks for the info/opinions. I'm leaning toward the 94-98 12v. They seem to capable of good amount of power and only needing 1 wire makes the swap that much easier..
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From: Snohomish, WA
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please elaborate more... I didn't see anything in that thread that spoke of quirks specific to the 98 12v... It's the same engine that they ran for 4 years prior 
I'm on my 2nd 98 12v, and there are no "quirks" that I'm aware of other than stone reliability
I'm on my 2nd 98 12v, and there are no "quirks" that I'm aware of other than stone reliability
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From: Snohomish, WA
Now don't you 98 owners take offense at the suggestion that your trucks may not be the end all/be all of 2nd Gen 12 valves, but...
Turns out that there are compromises to be made with every year. They are all still good trucks overall, though. 
Anyway, once again, (shorter version now) the '98 12-valve engine is a bit of an odd duck since it's built out of a 24-valve block, but drilled with SAE threads (versus Metric for all 24-valves) and some parts like main bearing cap bolts aren't the same length as 97-older 12-valves. And Evan (or someone) told me the '98s had more problematic P-pumps than the other years.
As for your analogy of half-year vehicles ending a vehicle generation (at least to a degree), the '98 12V did have problems. Many of the P-pumps crapped out prematurely, many of them not going even as long as many of the early VP44s! The intercoolers were not cast or the halves joined correctly at the inlet and outlet ports leading to substantial air leaks. Additionally, casting flashing wasn't properly removed from the inlet and outlet ports of the intercooler leading to additional air leaks. If a pressure test was administered to a '98 12V it usually had quite a few leaks throughout the entire length of the intake tract (turbo to head). BTW, Chuck Arnold of The PowerShop wrote a monthly column on this some years back in the "Nuts & Bolts" column of the RV periodical he writes for. In respect to the 12V engine, '97 was definitely the better year! The lure of the '98 12V is due to the Quad Cab and interior redesign aspects of the '98 model year truck...the 12V was just along for the ride so-to-speak.
So, not all was hunky-dory in '98 with the 12V engines.
So, not all was hunky-dory in '98 with the 12V engines.
I agree. The 98 12-valve is BY FAR the most troublesome of the 12V trucks. They have a ton of weird problems, too many to list here.
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first I've ever heard of problems w/ the 98... I prefer the 97 because of the interior. never heard of P7100's failing on 98's!
the way fittings are threaded really doesn't concern me
perhaps when the trucks were brand new there were issues, but I wouldn't have any fear buying a used one as I would imagine any leaks would have been fixed under warranty.
I loved my 97, but I've loved my two 98's just as much. haven't had any problems with any of them
the way fittings are threaded really doesn't concern me
perhaps when the trucks were brand new there were issues, but I wouldn't have any fear buying a used one as I would imagine any leaks would have been fixed under warranty.
I loved my 97, but I've loved my two 98's just as much. haven't had any problems with any of them