: 12 vs 24 valve cummins


Jonboy4542001
07-25-2006, 07:23 PM
Im looking to buy a dodge pretty soon with a cummins desel engine. I have searched all over the place but cant seem to find what im looking for. I need to know which engine is better all around. Such as cheaper upgrades, power, and most importantly dependability. Im pretty new diesel engines. If you can point me in the right direction or have any info of your own that would be great!!! Thanks

DieselRoverSwap
07-25-2006, 08:43 PM
Im looking to buy a dodge pretty soon with a cummins desel engine. I have searched all over the place but cant seem to find what im looking for. I need to know which engine is better all around. Such as cheaper upgrades, power, and most importantly dependability. Im pretty new diesel engines. If you can point me in the right direction or have any info of your own that would be great!!! Thanks


Since your motto is "break it fix it repeat" go with the 12 valve that has a p1700 injection pump.

The cheapest to bomb is that 12 valve.

You can just slap a edge or similar product to a common rail 24v.. So its easier to a certain level but more expensive. Not all 24v are common rail.. Once you run out of injector size or need to have them fixed on the common rail be prepared to spend some money. Both engines have their pros and cons.. Just avoid a '53 casting 24v block like its Richard Simmons on E...

http://www.cumminsforum.com/forum/

I will edit this with a direct link to a thread where the 12v vs 24v thing gets gone over like the 911 commision... Or you can just search 12 valve vs 24 valve on that site.





www.cumminsforum.com/forum

bigdreamin
07-26-2006, 05:39 AM
as far as 12v dependablity, i have a '96 with 288K the only work ever done to the engine other than a few serp. belts was a water pump, the key is doign your scheduled mant. religiously

getblown5.9
07-26-2006, 05:49 AM
yes the 24v from 98.5-2002 is not the most reliable from the factory. they have weak lift pumps, which in turn take out the poorly designed bosch VP44 injection pump...which costs $1-2K to fix. with an aftermarket pusher pump, and a fuel pressure gauge to keep an eye on it the 24v then becames almost as reliable as the 12v or 24v common rail.

the 12v will have a few things that need addressed as well, the Killer Dowel Pin is the biggy. you need to fix it, or else you will end up repairing all the timing gear when the pin falls out and destroys the gears. the 12v is also the cheapest to mod TO A CERTAIN EXTENT, you can get a 12v up to a lil over 300hp with just some injection pump tweaking and wastegate mods for pretty cheap. if you wanna go for 5-600hp, then you are looking at expensive stuff like delivery valves, injectors, governor springs, valve train upgrades, turbo swaps, etc. but the 12v P7100 pump will always be able to make more power then a 24v with VP44 pump if money is no problem for you.

bigdreamin
07-26-2006, 06:55 AM
yes the 24v from 98.5-2002 is not the most reliable from the factory. they have weak lift pumps, which in turn take out the poorly designed bosch VP44 injection pump...which costs $1-2K to fix. with an aftermarket pusher pump, and a fuel pressure gauge to keep an eye on it the 24v then becames almost as reliable as the 12v or 24v common rail.

the 12v will have a few things that need addressed as well, the Killer Dowel Pin is the biggy. you need to fix it, or else you will end up repairing all the timing gear when the pin falls out and destroys the gears. the 12v is also the cheapest to mod TO A CERTAIN EXTENT, you can get a 12v up to a lil over 300hp with just some injection pump tweaking and wastegate mods for pretty cheap. if you wanna go for 5-600hp, then you are looking at expensive stuff like delivery valves, injectors, governor springs, valve train upgrades, turbo swaps, etc. but the 12v P7100 pump will always be able to make more power then a 24v with VP44 pump if money is no problem for you.


about the Killer Dowel Pin, i am assuming it only need replaced if your doing performance upgrades? i see bd diesel sells them, any sugestions on what to look for when buying on afetrmarket?

jarvisjeep
07-26-2006, 09:34 AM
94-98.5 have the inline p1700 pump. Very reliable. They used the same pump on some of the bigger cummins engines too. Goto Turbo Diesel Regestry, they are the experts of the cummins engines. Reliabilty wise, buy a 97-98.5. They have the 215hp pumps in them. That pump is the cats meow in cummins modifying. my .2

jarvisjeep
07-26-2006, 09:40 AM
about the Killer Dowel Pin, i am assuming it only need replaced if your doing performance upgrades? i see bd diesel sells them, any sugestions on what to look for when buying on afetrmarket?
It willl come out and break the timing cover on any vehicle, modifyed or not. Its just a matter of time

superhawk2002
07-28-2006, 12:52 AM
It willl come out and break the timing cover on any vehicle, modifyed or not. Its just a matter of time


Probably the first preventative measure anyone should do when they get a 12V is fix the KDP..

Get a good low mileage 12V - you will be more than happy.

mattpark
07-31-2006, 12:27 AM
I'm not downplaying the importance of fixing the dowel pin, but they rarely do extreme damage. Normally if they fall out, they just get shot into the case and crack it. A tap with a hammer and some JB weld they usually seal up. In extreme cases they can break the gears/camshaft/anything in there. Every engine with the old style front timing case needs to have it fixed, even early 24v engines.

Get a 94-98.5 12v 5 speed. They are dependable and economical for what they are. I'm on my second, had a 94 5 speed, sold it with 340K on it (still perfect to this day with over 350K), and picked up a 98 12v 5 speed with 260K. Don't be afraid of miles on them.

crashnzuk
07-31-2006, 11:14 AM
I'm not downplaying the importance of fixing the dowel pin, but they rarely do extreme damage. Normally if they fall out, they just get shot into the case and crack it. A tap with a hammer and some JB weld they usually seal up.
Cracking the case IS extreme damage if you actually want to repair it right instead of a half assed trail type fix. JB weld may get you home, but is not adequate if you want to see 3 or 4 hundred thousand trouble-free miles out of it. My .02
Travis..

skipped_Link
07-31-2006, 11:28 AM
I am no cummins expert, but I thought I would throw in the fact that I just bought two 97 dodge truck with the cummins engine & nv4500 tranny, both trucks have over 500K miles I have not messed with one of them but the one truck I did mess with runs like a top,

PeteyPower
08-01-2006, 03:50 PM
94-98.5 have the inline p1700 pump. Very reliable. They used the same pump on some of the bigger cummins engines too. Goto Turbo Diesel Regestry, they are the experts of the cummins engines. Reliabilty wise, buy a 97-98.5. They have the 215hp pumps in them. That pump is the cats meow in cummins modifying. my .2

the 215 pump only came with the stick shift. It was from 96 to 98.5. i believe.

jarvisjeep
08-01-2006, 04:09 PM
the 215 pump only came with the stick shift. It was from 96 to 98.5. i believe.
Thanks. I am trying to memorize the years still:D.