I can answer a few of the newer questions:EFI big block?
No, not really. You CAN do it, I meant most (save for maybe some experimental) didn't come that way. Intake manifolds are now available off the shelf to accept standard bosch style multi point injectors, add your favorite brand of stand alone pcm. There are a few throttle body alternatives, adapting tbi to carb intake, once again with a variety of controllers.Chip a dodge?
Yes, no, maybe, kind of. In truest sense, physical replacement of the chip, it is possible but not yet accomplished. The circuit boards are coated in 1/2" of
polyurethane, which makes removal difficult. The chip is soldered in place, which means the board needs to be desoldered and socketed to accept a removable chip. Then the requirement for a chip burner and a bunch of blanks, along with the appropriate tuning aides. Final straw is the fact dodge wrote code in some format that is so hard to decrypt, no one spent the effort to do this to a truck that never sold that well in the first place. A few hard core gurus have cracked the 4 cylinder turbo code and rewrote it to their liking, one has recently offered to do the same for tbi trucks if there was enough interest. Personally, I view it as not worth it.
Then there is this thing called a "JET chip" just say no. Also say no to the stupid resistor tricks.
Finally, OBD2 (96-03 magnum v8) can be flash tuned via SCT. If you tuned dodges for a living, this is a viable option, because you can go in there and tell the JTEC controller to ignore all kinds of sensors that would be missing when you install this engine in an older chassis. Without the racer pro package, (lots of money) flash tuning alone isn't worth the trouble. SCT for big3 vehicles is like hondata for hondas, although hondata is by far the most feature packed oem tuner.Gear Ratios?
Most all had 3.21, a select few had 3.55, I am not sure if 3.91 was available in a ramcharger, maybe. The under geared scenario is the root of all evil on these trucks, especially with oversized tires. Your old chevy likely had atleast 3.42s, although I could be wrong. I don't really care what it had honestly lol. Dodges like some more gear. Plain and simple.Megasquirt vs cruise control?
Yes and no. MS will not control cruise. It is a fuel and spark controller, that is about it, although it has some other basic outputs like fan/nitrous/ ect ect. BUT yes, you can still have cruise and a stand alone pcm. Before efi, carbed vehicles still had optional cruise as well. They had their own control module built into the cruise actuator itself. Cruise wiring is relatively simple, there are 3 solenoids inside the actuator. Furthermore, hot rodders like to install cruise on their hot rods. They sell aftermarket controllers for around $100 which look stock and handle speed control even if the vehicle didn't have a speed sensor (flying magnet). It can be done, and can be done cheap.Pulling MIL codes on a dodge?
I assume you have the red brick MT2500? NOT NEEDED. Almost all obd1 vehicles have a method of retrieving codes without any scan tools. Fords using test light and STI pin, GM jump ALDL connector A-B pin, and dodge....turn the key on/off 3 times within 10 seconds. All produce a flashing morse code type display of the MIL light. Count the flashes, write them down, compare to the list. Dodges use a 2 digit code. 3 codes are of no concern for 4x4s. #12 (batt disconnected in last 50 cycles) #37 (lockup solenoid circuit failure- 4x4 didnt have lockup converters
) #55 (end of test)MegaSquirt and reliability?
It seems to have been proven as a very robust pcm, and cheap. Must more durable than that junk 88-89 SMEC pcm dodge used. Which is actually 2 separate circuit boards (power board for outputs, logic board for inputs) and using a spider web of internal jumper wires to connect the 2. If any of those wires break or otherwise become damaged, the pcm is junk. In a worst case scenario with the MS, you can always carry a spare since they are cheap. It can already be loaded with what ever program you so choose. Whether it is fully refined or merely a crude limp home tune. Furthermore, the board itself can be repaired instead of replaced, and every single part is available individually and widely available through local electronic outlets. Sure you can buy a replacement stock pcm from autozone....it might be back ordered for a week and most definitely any custome tune you had before is for ever gone.Mopar clueless?
Nah, it's just an engine....with very little different from most any other efi engine as far as the basics go. Uses the same 5v reference, same analog signals (MAP, ECT, TBTS, TPS, O2), same waveforms for most of it, same pulsed ground commands, low impedence (2ohm) injectors, coil testing is the same principle, the 1 single difference is the 8v square wave hall effect distributor sensor. Nothing major there.No power, quiet exhaust, only cat
Perhaps you simply have a plugged and failing cat? Its 20 years old, anything is possible. Simple backpressure test could tell you. Or cutting it off. Or possibly even some WOT testing with the o2 sensor unscrewed. (they run in open loop at WOT anyways) and the open hole may relieve some pressure, freeing up a little power, indicating a potential clogged cat.
Doing a compression test WITH THE ENGINE RUNNING can immediately indicate a worn cam lobe. Yes I understand most people do a static cranking compression test....no one said you have to do it this way, you still get numbers, they are just different, and must be interpreted differently.
Simple vacuum gauge will also tell you a lot.http://www.secondchancegarage.com/public/vacuum1.swfBig cams on mopar efi?
Well they won't help a truck with acceleration problems, but it can be done. The secret is to use a wide LSA. Most reputable cam companies such as comp cams will provide a custom ground wider LSA variant for very little extra. 114* might be a good place to look. This will provide a smooth idle which will provide a smoother MAP sensor waveform as viewed on a scope. Less rapid fluctuations=happier pcm.