killed300ex

Just purchased a 94 12 valve with 156k on it. This is my first diesel and after just half a day of driving it I am already hooked. I dont think I will ever be able to go back to a gas engine. Have some questions though. First off is I am looking to put a new intake and exhaust on it I have decided on running stacks on mine. Wondering how you guys are doing it with no mufflers ect? Do diesels not require mufflers for inspection? (I know this might vary state to state) I know all gas engines have to have them in NH and I dont know if I will be able to fit a muffler while running stacks. Also What is a good intake to run? Is there any easy way to tell if the injector pump or lift pump needs to be replaced/rebuilt? The truck seems to have plenty of power but I am looking for more get up and go.
Thanks
Evan

jester1542

Depending on your setup you may not see much power improvement from either an intake or exhaust. A larger exhaust should lower your EGTs if you have other mods.
Most will suggest an upgrade approach something as follows:

gauges
KDP
3K governor springs
fuel plate
before more extreme upgrades

displacedtexan

Welcome to DTR, and congrats on the truck.

Many guys run without mufflers, I usually have in the past, but at the moment I have one on. OK doesn't even have vehicle inspections. They probably should with the crap some of the meth heads drive around, but oh well... Rip Rook (sourceautomtive.biz) sells a "sneaker" muffler, it is a muffler with 4" pipe straight through, so you can pass a visual. I really have no idea what NH inspections do.

Odds are your IP is still good. The P-Pumps are a pretty tough to kill pump.

To get more power out of your truck the first and foremost investment is a good set of gauges. These are a must anytime that you are adding more fuel to your mix. At the very least a Pyro, a boost gauge is really nice to have, and if you have an auto, a tranny temperature gauge as well.

A governor spring kit, referred to as a GSK is a wonderful investment that widens your normally narrow power band from the 12 valve engine and allows you to fuel hard to at least 3200 RPMS or so, before it starts to defuel, this is all dependant on your governor arm adjustment and your plate positioning.

A Torque, or fuel plate should come next. NO one really follows the plate guide anymore and the most popular plates nowadays are 100, 10 and a zero plate.

More commonly referred to as fuel plates, they come in different numbers to explain how "aggressive" (for lack of a better term at the moment) that they are 11, 10, 8, 6, 5, 0, and 100, zero being a flat plate that bombards the pump with fuel, and a 100 being a ten plate curve with no top end defueling, much like the zero.. The plate goes in the P7100 injector pump, It goes under what is called the AFC housing, which has a little starwheel on it, the starwheel can be accessed with the removal of the hex dealy using the the right hex head size plug, and you loosen it for more smoke, and better lower end, and tighten it for the inverse. Use a good screwdriver.... furthermore... You will see four screws there where the starwheel is, two that are flat, one that is possibly a breakoff screw that can be a real pain to remove, take a hammer and good screwdriver and bang the tar outta it, it will come off, if that fails, left hand drill bit... Looking down the driver side, the top left hand is the breakaway, and the top right is a regular screw as well, the bottom two are 8mm bolts and you need to get around to one that is in the back of the AFC housing that holds that fuel shutdown solenoid in place...

The other tricky bolt is the one (if you look down from the drivers side) behind the Fuel shutdown solenoid (electronic hooked up deal that bolts in front of the injector pump, easily removed with in my case an 8mm (and most should be too) socket and pull out the two bolts. when you undo those you will notice that there is one in the back that is holding the housing, you can just loosen the one in the rear using a deep 8 mm socket and just move the shutdown solenoid out of the way, (downward) and then you can get to the plate..

When you are in there its simple, you just remove the stock plate and put the other plate in place of that one. NOTICE you have some play here. Sliding it forward of the stock position will net you more power, sliding it back will reduce the power.

Now put it back together and you are done. Installation is simply the reverse of removing it. Having a magnetic tip screwdriver REALLY HELPS. As you are putting the AFC housing back on you will notice that you can also slide it forward and backwards a bit as well, sliding it forward increases the low end fueling as well.

To increase the boost you will usually have to plug the wastegate line, it is the one that goes to the wastegate from the back of the AFC housing, you can get a boost elbow from many different vendors to increase the boost, or some just disconnect the line and plug it by clamping a screw in the end of the hose to keep anything from going in the hose.

Install time, for a newbie, well it will take you about a couple of hours at most. Your only real problem might be that break off screw, especially if your truck is stock, However, nothing a good strong screwdriver and some persuasion cannot take care of.

Which plate is right for you? A 10 is generally considered the best all around plate, many guys run a 100 for a little more to end, and guys that drag race and such tend to like the really heavy low end fueling of the zero plate.

There is no one setup that works for everyone, you may have to make some adjustments to the plate, AFC position, or starwheel to get it set to your liking and needs as far as power, responsiveness, and smoke.

Either ways, you are going to need a clutch or tranny work if its an auto. And your EGTs will tell you when you need an intake and exhaust to help keep the temps down. Neither of them will gain you power alone, but they can help you get more from the fuel that you already have.

The next step is usually advancing the timing, which requires more advanced skills, and special tools.

jester1542

One other thought as mentioned a folks advance the timing of their trucks to around 15.5 degrees which helps performance, sometimes fuel economy, and a couple of other things. As also was mentioned, it is a more technical change which isn't really hard but does require special tools. If you decide to have the timing done you might want to have the KDP checked at the same time since the KDP fix requires getting under the front cover which also provides access to the timing gear assembly. Combining the efforts can save you a few dollars.

killed300ex

Thanks for the replys they are a big help. I am thinking about getting a set of guages and installing a #10 fuel plate and doing exhaust(Mainly I have always wanted to put a set of stacks on a pickup) I am tentative about doing the work myself as its my first diesel. Anyone in the NH area interested in helping me install them? Will compinsate with beer and $
Thanks
Evan

Box5

is ur truck a auto? if so, be careful with the mods you do or the tranny will act up.

killed300ex

unfortunitly its an auto. I was looking for a 5 spd but found to good of a deal to pass up. I deffinitly know about dodge auto trans as this is my third ram 2500. What do most of your cummins idle at? I think my idle is high at around 1000 rpms?
Thanks
Evan

Mslaughter

I know in some states the turbo is considered a muffler. So you might wanna check to see if that applies in NH.

dieselfuelonly

My 3500 is pretty low, its about 500ish. I should turn it up a bit. My 2500 idles at about 800-900 RPM.

Willy91

No inspections here, as stated above there are several things that can be done to make your truck run like it should. The way I would do it if you're not looking for to much power is

Guages
Intake(BHAF is a pretty cheap way to do it)
Exhaust, your choice here, you can buy a kit or build it yourself
For the tranny atleast a good valve body, if you can afford a torque converter would be nice to.
HOme grind a 100 plate
3 or 4 GSK, I would just do the 4 and be done with it
16 degrees of timing

That would set you up pretty good, and the truck would deffinently be a runner.

A couple good companys to buy these parts from are Pure Diesel Power, for your guages, and GSK, and then for the tranny parts I would get ahold of either Dave Goerends, or HTS transmission.

*****

dieselfuelonly

Just remember with the 4k GSK you have to upgrade you're valve springs or be really careful with you're right foot.

jester1542

The truck should idle between 750 and 800 in drive with the AC on when warm.

killed300ex

Just went to fill up with fuel tonight. OUCH I know I had a heavy right foot but I only got just over 10 mpg. What are some common ways to get some better gas milage? Other than keeping the right foot from the floor. Seems like something must be wrong.
Thanks
EVan

displacedtexan

Timing helps the most on MPG.

Are you running oversized tires? That could be throwing your speedo off and skewing the numbers.

Also could be a bad lift pump/overflow valve.

killed300ex

I do have slightly larger tires 285-75-16 I know it would make a small differance maybe 1-2 mpg but thats it. How can you tell if its a bad lift pump?Thanks
Evan