12 valve cummins differences?

[otisd85]

i have a 1990 crew cab chevy im considering a 12 valve swap into. i havent found a motor yet nor do i really know what im looking for. what are the differences in 12 valves? i know the 89-93 have a different ip than the 94-97.5 but when you look up a pump theirs a difference between auto and manual trans, whats up with that? whats the difference between the motor with 1 valve cover or 6? what other things do i need to know bout the cummins before i pick my donor.

thanks in advance
otis

 

[shortbusdriver]

94-95 auto - 160hp pump
94-95 manual - 175 hp pump
96-98.5 auto - 180 hp pump
96-98.5 manual - 215 hp pump

All will make serious power but the 215 pump will make it easier. I personally like the 180 pumps the most for various more technical reasons.

 

[argve]

I wouldn't worry too much about making sure you get the 215 pump... I had a 95 with a manual and you can ask some of the guys here what kind of power mine tossed down. Mine was a power house with probably under a grand in mods. Trust me when I say it really doesn't matter as mine really had too much power for a daily driver as I didn't really use all the power but it was fun when I wanted to play. But if you are going for top hp honors then I would shoot for the 215 but if you are looking for a daily driver then anyone of them will work just fine. You would be flat amazed what you can make the lower hp pumps do.

 

[otisd85]

can i buy a 89-93 truck and simply put a p7100 pump on that engine or would there be more to it than that? the reason i ask is it seems like it would be easier and possibly cheaper with the 1st gen as far as getting the engine/nv4500/np205 with a passenger side drop, than finding a 2nd gen with a nv4500 and adapter to a chevy np205 then changing either the output on the tranny or the input on the t-case.

when i do this swap i am going to have the engine rebuilt and i intend on replacing the turbo, injectors, and pump. in my research on the pump so far there is quite a few upgrades you can play with on the p7100 as far as modifying the fuel plate and changing the governor springs, so after you modify the pump are they all equal?

 

[otisd85]

that sounded very uneducated! what i meant to ask was can you take a 160hp pump and put a stock 215hp fuel plate in it and have a 215hp pump or is there more to it than that, or what im really trying to get at is if the pump is being rebuilt does it matter what pump i end up with?
i am looking (hoping) for something in the 450-500hp and 8-900ft/lbs range as an end result, and i am wondering if a 215hp pump will get me there easier than a 160 or if they are equally capable of making those kind of power numbers, if not, why not, an what is the difference?

 

[shortbusdriver]

The internal cam, plungers and barrels, delivery valves, govenor assembly, and plates are totally different between the 160 and 215 pumps.

 

[otisd85]

so can the both pumps be upgraded to make the same amount of power or is it easier to start with the higher hp pump from the start?
can the p pump be used on the 89-93 engines or do you know whats involved in upgrading the older cummins to install a p pump?

 

[shortbusdriver]

The cost to upgrade a 160 to flow the same as a 215 will cost you more then a whole different pump will. Like I said, ANY of these pumps will make SERIOUS power, more then you will ever need.

You can p pump a 89-93 but you have to change pumps, injectors, injector lines, mounting bracket, timing case, and timing gear.

 

[otisd85]

i realize a performance p pump is going to be pricey and even more so without a core to turn in, but has anyone come across a kit with or without the injectors to put a p pump on the older cummins or do i have to find another donor to get the parts to retrofit the pump

 

[otisd85]

been doing some more research and come up with some more questions.

is there a difference in the bellhousing from 89-93 and 94-98.5? the reason i ask is because ive seen threads about people wanting to upgrade to an OD auto and run into problems.

what years did cummins have the getrag behind them and what years was it the nv4500, or did they overlap, and is there a way to tell without looking at the truck when the seller says it has a 5 speed but doesnt know the difference between the two?