i wanna learn how to madify a cummins and other diesels

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tyler_s18

tyler_s18

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i am looking at getting a first gen cummins with the 12v engine. those cant be chiped they are mechanical not computerized so what can i do to make it fast lol. i like the chip cuz you can go from mileage to tow to performance and back and forth by the push of a button. is there any way to do anything like that to the older ones? where can i go to learn about it all lol? the diesel instructor has a 12 sec street first gen cummins. he wont really tell anyone what he did to it lol. so what kinda things would he of done or what would you do? the one i am looking at is auto 2wd ext cab long bed with single wheels on the back (no duely) thanks tyler
 
Actually diesels are simplier than gas engines cuss there's no spark or spark timing to worry about but there is diesel injection timing, how much and when, hence the rechipping of the ECM on newer diesels. Most first gen. diesels (like the Jimmy's and the Cummings 350 and 400) used fully mechanical injectors that were operated from the camshaft through lifters, push rods and rocker arms (one per cylinder) or other engines like the Mack used a timed high pressure fuel pump delivering precise amounts of fuel to injector nozzles (one per cylinder) which were basically a spray nozzle with a check valve just upstream of it. The go peddle operated a rack affair, on the cam shaft operated engines that would increase or decrease the actual fuel pumped by each injector whereas the high pressure pump design had a single pump plunger that also pumped a precise amout of diesel to each injector and was also controlled by the go peddle. I suspect in your instructors case he's using a big assed turbo or even 2 and opening up the flow orifices on the injectors eg. more fuel and more air. There was an old trick that truckers would use in the old days to help pull the mountain passes before the really big diesel engines took over and that was propane injection (you didn't hear that from me:toothy10:). Just a little bit mind you and they'd watch the EGT (exhaust gas temperature) guage to make sure they didn't melt down the engine. Maybe that's also what he's using. He may even be injecting water to increase the charge density therefore horsepower.

Terry
 
ok thank you. i learn best by taking it apart and playing with it but that was a lot of help:) i know his is one turbo and it didnt look to much bigger then the newer cummins turbos i have seen. could you put a cam in it that opens the injectors longer or open farther?
 
tyler_s18 said:
ok thank you. i learn best by taking it apart and playing with it but that was a lot of help:) i know his is one turbo and it didnt look to much bigger then the newer cummins turbos i have seen. could you put a cam in it that opens the injectors longer or open farther?
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Interesting question, both no and yes. On the old Cummings engines you couldn't change the stroke of injector plunger as a matter of fact there was a clearance tolerance that you had to shoot for between the rocker arm and plunger head. You could go to larger orifices in each unit injector kind of like going to a bigger plunger but those changes have to be done on a special test rig/flow bench that also calibrates each injector. I'm pretty sure though that you could change the timing of the injector opening by adjusted a slotted gear or pinned on the end of the camshaft but this would also change your intake and exhaust valve opening timing also. The valves and injectors work off the same cam. I'll pull my diesel engine manual (the big one) and see what it says tomorrow, it's been a while. One other thing to consider is the old and new turbochargers had internal exhaust waste gates that controlled the RPM of the turbo therefore the boost pressure to the engine. He may of cranked up the waste gate controller to boost the air pressure to the engine but god only knows how much and if you really crank up the boost you also have to have a intercooler to cool the air after you boost the crap out of it.

Terry
 
ok lol i know his is intercooled so maby that is what he did. i also heard there is a plate on the throttle body (or what they use for that lol) that you mess with and then it blows black
 
Okay I will take a stab at

built tranny

bigger 4 or 5 in turbo back exhaust

timing adjusted

0# fuel plate

GSK (3000 or 4000 rpm)

headwork

intake or filter

torque converter

shift kit/valve body

T-turbo upgrade

bigger injectors ( HP rating ie : X100 for 100hp injectors)
 
Hehe......

The skinny on the first gen cummins........

They have a Bosch VE injector pump, gear driven off of the cam gear. The VE is a single piston rotary pump, good for moderate HP, mine has probably an honest 350 at the rear end, and, oh, maybe 650-700 pounds of TQ. To start out, you need a boost guage, and a Pyrometer. Boost should be measured on the plug under the intake of the manifold, Pyro should be in the joining of the two sections of the ex manifold, before the turbo. Pyro goes like this. 1200, OK, 1250, mmm, ok for a little bit, 1300, hit it and back off, 1400, your brave, don't keep it there long 1600, I have hit it, didn't seem to hurt anything yet, but it scared me, and cumins says my pistons are bubbled. Pyro and boost are not only detrimental, but needs for a guideline.

Mods to the VE pump.

First thing, is to screw the start wheel all the way down on the "ach"? (The boost sensor, this will make it smoke some when you hit the throttle, boosts quicker, then, you grind the pin, or get a bullydog ol smokey pin, I ground mine, line the diaphram up so the skinniest part of the pin is facing the front. Then, pull the fuel pin screw out, break the collar off of it (count your turns) and fix the threads, grab a 2x4, pull the....... You know what, I am going to find a damn link..... brb
 
Demon Speed, what size engines are you talking about? Sounds like the larger medium/heavy duty engines?

There are a few different "Gens" for the dodge diesel:
The "First Gens" are from 89-93, they were the boxier truck and didn't come with intercoolers till 91. These trucks have a mechanical injection pump called the VE pump. These trucks can be tweaked with for "free" HP but these are smaller pumps and on fuel only will max out around 330-375HP depending on how well they are set up. These truck make great torque number anywhere from 650-900ftlbs. I've seen one truck up to 500hp but at that much power the truck becomes unreliable, his engine would "run away", rev up all on its own. These are 12v motors and for a while the aftermarket injector selection was meager, now most of the injector companies can make you a custom set rated at just about any HP you want.

2ng Gen trucks came out in 94 and the body style went to 02, but received some updates in 98. 94 to 98.5 trucks came with 12v P7100 mechanical pump. 98.5-02 came with the VP44 pump which was their first electronically controlled pump.
The P7100 pump (P-pump) can make some serious power and still be very reliable. There were a couple version of it 160,180, and 215hp pumps. The 215 pump are more sot after cause they have some bigger/better internals and can support more HP... easily 700-800hp. There are aftermarket pumps called 13mm and 14mm p-pumps and that refers to the pump plungers. These pump can spin the motors up 5-6k rpms and make up to 1500-1800hp.
These pumps have fuel screw, springs, and "plates" that you can change out, modify and do all kinds of things to make power. But yes these aren't "on the fly adjustable".

The 24v Vp44 truck were from 98.5-02. The vp44 has a bad rep for failing all the time... But in reality it wasn't all its fault. The vp44 is lubricated with diesel fuel instead of motor oil like the Ppump and VE pumps. The 24v trucks came with a really crappy electric lift pump that supplies the VP with fuel. These lift pumps would go out anywhere from 10k-100k miles on stock vehicles and in no way could keep up with mildly modified engine. Electric fuel pumps are meant to push fuel instead of pull fuel as well, these lift pumps were mounted on the side of the engine straining to pull the fuel up to the VP. Most people buy after market fuel pumps and install it on the frame back by the fuel tank eliminating the stock lift pump all together. The VP is a smaller pump and maxs' out in HP much sooner then ppumps. On fuel only they are just getting to 700-850 or so hp with aftermarket VP pumps. They are just breaking the 1060hp mark with nitrous.

Now all of these motor use a "mechanical" type of injector. It uses shims to adjust "pop off" pressure, when the injector injects.

In 03 and newer trucks they went to a Common Rail injections system. This system's injection pump is called a CP3 and all it really does is create pressure. The injectors have an electric solenoid and can be controlled a lot more then the previous injectors.... There is all kinds of crap on these truck and I dont know too much about them so I'm not going to get into these.


But some other things to think about is most automatics SUCK when they are stock behind a Cummins. It seems like they basically took a small V8 trany and stuck it back there. The design of the trany its self is great! But the stock valving and pressure are too weak. An aftermarket auto is one of the best upgrades I've done and really changes the characteristics of the truck.

There are a lot of things you can do to these trucks. Its crazy how much HP you can get of these and still get great fuel mileage and drive it everyday. Cummins has a 1/3 less rotating parts then a powerstroke or duramax. Working on a cummins is very easy. But watch out... it gets addicting and your other projects might get neglected.
 
http://mopar.mopar1973man.com/tips/cummins/1stgen/inc-pump/inc-pump.htm

Pics of my cummins intake, made by TWorline at 1stgen.org and stock air filter mod, mad man with a sawzall.........

S8001159.jpg



S8001158.jpg


Since the pics were taken, it now has a HX35/40 on it, instead of the HC with the HX impellers like in the pics. Oh, the pyro probe, that is shown too.
 
Also check out some other forums like cumminsforum.com or TDR.com or even Competitiondesiel.com... Although the CompD guys are a little more hardcore.
 
There are a lot of things you can do to these trucks. Its crazy how much HP you can get of these and still get great fuel mileage and drive it everyday. Cummins has a 1/3 less rotating parts then a powerstroke or duramax. Working on a cummins is very easy. But watch out... it gets addicting and your other projects might get neglected.
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Mine tows every day, 8K+, runs around town, and get an average of 19.5mpg.
As far as addicting, little gas engines, just seem boring now. The baddest RB truck motor I have seen doesn't hold a tea light candle to the cummins, and burns 3X the fuel.
Take a look at the oil filter, I wrote the mileage on it, look carefully, that isn't 34,5XX, thats 345,***....... Yyyyyeah, do that with a gas engine!

This winter I am taking my "rebuilt too many damn times and failing again" Getrag out, and putting a 13 speed in it. Just to be cool, and to have a gear for everything........
 
I want to see your passenger mirror mods for holding that flag.
Does it affect MPG?
Do you fold it down to go under bridges and wires?
Special permit?

I also just noticed he asked how to "Madify" a cummins... I'm not sure how to make my cummins mad, but if I accidentally step on the foot feed a bit too hard, at a bit too low of an RPM, it sure "Madifies" the people behind me.......
 
My buddy just put twin turbo's on his older 12V, he's got 5 inch exhaust,big injector,modified P-Pump the list goes on He's the one that got me into the 12V CTD.He tried it out and it hit 55 lbs of boost then poof went the HG:toothy10:
 
My Buddy has twins on his 02, with New era 200's, I think, edge w atitude, ect.

We hit 60 all the time, I wonder if the 24V takes boost better. My 1st gen runs up to 45, no issues yet.
 
megajoltman said:
My buddy just put twin turbo's on his older 12V, he's got 5 inch exhaust,big injector,modified P-Pump the list goes on He's the one that got me into the 12V CTD.He tried it out and it hit 55 lbs of boost then poof went the HG:toothy10:
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Did he do head studs? I have a few friends with twins only one of them have studs and o-rings the rest just have studs and they see anywhere from 55-75lbs. Both blocks have the same number of head bolts.... some just get lucky with HG. I did, I was over spooling my HX-35 and could hit 47lbs. I installed arp studs when I got the HX-40.
 
Nitrous340Dart said:
Also check out some other forums like cumminsforum.com or TDR.com or even Competitiondesiel.com... Although the CompD guys are a little more hardcore.
Click to expand...

Yea, when tyler said first gen Cummins I thought he was talking about the larger units not the pickup engines.

Terry
 
Nitrous340Dart said:
Did he do head studs? I have a few friends with twins only one of them have studs and o-rings the rest just have studs and they see anywhere from 55-75lbs. Both blocks have the same number of head bolts.... some just get lucky with HG. I did, I was over spooling my HX-35 and could hit 47lbs. I installed arp studs when I got the HX-40.
Click to expand...

He does now:-D head studs, decked and o-ringed. He only pushed 55 lots more in it but was trying to save the HG for just a little while lol

This thing is unreal how it runs and pulls:cheers:
 
I kinda of put my truck on the back burner to get the dart running and mobile at least.Then its 12V BOMBing for me !

lited4x4002.jpg
 
wow this a lot of info:) thank you i will read it a lot lol. i am hopefully getting a powerstroke then tradeing it as quick as i can for a cummins or at least a dirtymax lol. so it will be a while before i get it but i want it to be fast quick lol
 
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