ISX

The middle of the tire formula (245/75/16) is a percentage... The 245 is the width of the tire in mm's. The 75 tells you how much of the width of the tire the sidewall height contains. As in, from the edge of the wheel to the outer part of the tire, is 75% of 245. Obviously this is America and we need English units so you convert 183.75 (75% of 245) into inches by multiplying that by 0.0393700787, now you have about 7.23", so if you measured the sidewall on that tire (the stock size) it would measure almost 7 1/4". So to get tire height you multiply 7.23 by 2 (since there are 2 sidewalls in tire height) and then add the wheel size of 16". Now you have a 30.5" tire.. Let me know if you don't understand that. Alright I updated the file it to make that part a little clearer.

Spent a while making this thought you guys could have some fun with it too. You have to have microsoft excel for this file to work. Should work with any version.Don't mess with anything but the highlighted blue things or you might erase my formulas. If you do manage to delete it all and make it go nuts, just delete it and redownload the one here.. Speed-RPM 2.xls

You realize I been sitting here dieing to know what your voltage is :ahh: Yes I remember you disconnect yours :p

I thought you would have already had it charted and graphed months ago knowing you

Alright it's 33*F out this morning, voltage is rock solid at 12.62V. Turn grids on and it dropped to solid 11.09V. Now, what does yours drop to?

Sureeeee, make me go out and test the voltage why don't you!Alright the grids aren't even turning on. Woulda thought after 4 hours of sitting in 32* it would turn them on but whatever floats it boat. I'll check it in the morning. What is your voltage when they're on and the truck is off?

New movie, 2 cycles of the grids.

Yeah I need something to get the surface area up. One pipe bent inside the exhaust shaped like a water heater element just doesn't have the surface area. I have 5" from the turbo back so I have plenty of room to work with putting pipe in there. But it's a PITA to weld in such a tight spot. The copper around the exhaust or even exhaust manifold sounds very plausible. I know copper bends like crazy which would work so much better than the steel pipe that I have to heat and then risk kinking when I do bend it. Plus copper pipe wound around everything would look neat!

I ran a pipe into the exhaust hitting off the heater core but it's not doing much. Need longer piece of pipe, or slow the flow, it's going through too fast.

It does sound more complicated than just a boost leak the more you talk about it. You won't get any smoke with a leak though because the computer will not give much fuel to an engine with no boost, and having no fuel and no boost you would have no power. This is true even back to 1st generations, they have a spring that the boost pressure pushes against which then lets the pump give full fuel once boost is built. If trucks didn't have anything like this, the guys that floored it at stoplights would black out the intersection every time.

I can say for a fact that synthetic starts much more smoothly when the temperature drops below freezing, especially 0*F and below. I run the amsoil also. I take it you cringe at the price but you save a lot buying it. 25,000 miles compared to 5,000 mile oil changes pays you back over the 25,000 miles. Filters and dino start to add up. Synthetic also does not coke as bad when the turbo is hot and you shut the truck off and is supposed to keep gaskets and seals from getting dry and cracking. That said, if your nice to your truck dino is fine too. The coking isn't much of an issue when you let the EGT cool to 300*F before shutdown. Gaskets should last a long time with dino or synthetic, up to 150k miles or more. I run synthetic because it ends up being cheaper and it makes a world of difference in winter. Amsoil is probably the best there. As for dino, rotella or delo 400 seem to be some of the most widely used dino oils.

Was your boost pressure the same? Sounds like you have a leak between the turbo and intake manifold somewhere.

It allows the engine to breath easier and the filter lasts a lot longer. Some people claim more power and the turbo does seem to light sooner. I just don't think it does anything for mileage.

The reason people get BHAF's is because turned up trucks need more flow from the filter near the top end (when you build over maybe 30psi). I don't think there is any mileage effect. If your driving economically, then your not going to need much air flow, so any filter would do. Speed is the main factor of mileage. I lose 2mpg per 5mph over 55.

Hmm, well tell me how this does. The injector on a diesel works much like a gas engine's spark plug in that it determines when the explosion inside the combustion chamber happens. The only difference is that diesels do not use a spark, they rely solely on the heat of compression which ignites the fuel the instant the injector shoots it into the chamber. The injector fires based on a set pop-off pressure. Once the fuel in the injection lines reach a certain psi, the injector opens instantly pops open and shoots a set amount of fuel in. The p7100 pump has 6 little pistons that build pressure for each individual injector. The bore and stroke of that piston determines how many cc's of fuel is pushed through the injector. After pressure is reduced in the injector lines, the injector closes and waits for more pressure to build then the injector fires and the cycle goes on. Flow rate of the injectors is not only based upon the injection pump output, but also the injector hole size and number of holes. At the base of the injector are tiny holes in which the fuel shoots from. The bigger the holes, the more flow of fuel there will be. The same goes for number of holes, the more there is the more flow there will be. Pressure will be reduced as flow is increased which may affect atomization of the fuel, which may reduce efficiency.

Well if people know how things work then they become more knowledgeable about them and are able figure out what is going on with their truck. Not to mention they will know what to do when something does happen and should be able to go past that and create a solution for the problem beyond my solutions because they will know exactly how it works and may have a better idea for the fix than I.Give a man a fish/teach him how to fish..

Well I'm trying to hit all the common things but its hard to remember them all. I had a dream about the 5th gear nut, woke up and wrote that part I notice a lot of people also just tell you something like, the temp gauge fluctuation is normal, period. I wanted to let people know why things happen. Nothing I hate more than just having to accept something as being fine just because someone said so, I like knowing why it is fine.. I got more things to throw in that I have to wait til I'm at home to add where I have tools.. It's turning out better than I thought it would though

I will be editing this continually as I think of more.. Thinking of buying 12v, what do I need to check? Has the Killer Dowel Pin (KDP) been fixed? How is the front end play? When did they last change the bearings? Auto trans -- Does it go into gear well? Is there a lot of slippage in the torque converter? Check and see if the fluid is burnt. Make sure it goes into all gears and locks the torque converter when warm. Manual trans -- Feel for clutch slippage and how well it goes into gears while driving. Ask how many times the 5th gear nut came loose and how they fixed it, be weary if they say they welded it as you wont be able to remove the nut if needed if they did.. Check the dash as long periods in direct sunlight will make them hard and crack. There are 4 bolts holding the AFC housing, one of which should be rounded over (tamper proof) looking the same as the top of a rivet, if they are all regular bolts then you know they have got the tamper-proof one out and messed with the fuel plate (turned it up) and if its an automatic truck, they might be selling it because the more power they got out of it is making the trans very weak. Lastly, encourage them to let you start the truck "cold", as in having not been warmed up prior to your arrival. Any hard starting issue might mean your getting into a money pit, especially if its over 32*F out. What is all the Killer Dowel Pin commotion!? The Killer Dowel Pin (KDP) as its been nicknamed, is an alignment pin behind the timing cover on the front of the engine. It works its way out of position and falls out wrecking havoc. Click here for a writeup on it. I lost 5th gear! This is a common problem on the NV4500. There is a nut on the tail shaft which "holds" 5th gear in place. When the nut works it's way loose, 5th gear slides down the shaft until it loses contact with the splines. It is a very simple fix, though to permanently fix it there are a number of solutions. To get to the nut, you must drain the fluid out, remove the driveshaft, and take the tailshaft housing off. That is all that must come off, only the very end.. Then you will see the nut unscrewed from the threads just flopping on the shaft. Screw it back on and get it as tight as possible. There are updated nuts at the dodge dealership that contain set screws to tighten the nut down even further. People have tack welded them but that does not seem to work, if you don't care about ever taking the shaft out or disassembling the trans, then you can Tig weld it all the way around and that is said to cure it for good. There are also fully splined shafts available that allow 5th gear to slide wherever and always be in contact with the splines (the stock shaft is not fully splined which many believe is the root of the problem). If you put the nut back on and just tightened it there are ways in which you can prevent it from working loose. Avoid lugging the engine in 5th, basically keep the engine above 1500RPM, when you lug it, the nut feels each piston stroke and it hammers the nut off. The second thing is to avoid jerky driving in 5th, as in letting off then stepping on it in a jerking fashion.. this torques the nut off.. Cruise Control and/or Vents only blowing out defrost? This is a very common problem concerning vacuum lines. They will pop out of their rubber connectors or crack causing leaks and then your vents have nothing to run them so they default to defrost and since the cruise works off the vacuum too, it stops working. You will see the little black lines that stem from the vacuum pump that is located behind the power steering pump. They run to the the cruise control unit located under the driver side battery and they also run along the firewall right below where the back of the hood would shut. If only your cruise control is not working, the unit for the control under the battery may have issues and need to be tested. ABS/Brake Light is on? Check the connector on top of the rear differential, check vacuum (94-96'), check the brake switch, also check the ABS sensors. My dome lights and radio don't work! This is something most people overlook because of the labeling on the fuse panel. The "I.O.D." fuse is the one that controls the lights and radio, even though the radio has a separate fuse, this one still kills the radio. This fuse is also the one that has a yellow fuse puller on it, the puller only pulls the fuse out a little ways so that the contacts are not holding the fuse tightly allowing you to get the fuse out with ease, so don't try and rip the fuse puller out of the fuse panel as it is only going to go back maybe 3/16". Why does my temperature gauge fluctuate? Dodge came up with the idea that to be king of the pulling trucks it needed a big radiator.. Without a load, the radiator is way too big for the engine's heat output, causing every opening of the thermostat to drastically cool the engine because of the inrush of cool water. When the thermostat closes, the engine heats back up and then the thermostat opens and cools it off again. This cycle continues until the engine and radiator come to an agreement with temperature and then the range between opening and closing of the thermostat is only about 10-20*F. When pulling a heavy trailer, the radiator is now sized to perfection and the engine temp should stay around 190-205*F. Why does my voltage gauge fluctuate on cold starts? When it is below 60*F ambient temp, you now have to wait for the "wait to start (WTS)" light to go off. This is because the grid heater is heating the intake so that the air is warm enough to start the truck with ease. After the truck starts, it goes into the post-start cycle and will turn the grid heaters on and off to maintain a warmer temperature, this is why your voltage gauge goes up and down since the grid heater draws a lot of power. This post-start cycle will last a while depending on how cold it is. I have seen mine continuing to run up to 5 min past startup, but the longer it runs, the shorter it lets the grid stay on, eventually getting to the point of 1 sec or less then finally just staying off. The other way it shuts off is by going over 20mph. Click here for more info. Is the oil pressure really 40psi all the time? No. The factory oil pressure gauge is merely an indicator showing you have pressure. It is either on or off.. If you hook a real gauge up to it, you will see the pressure go up and down with RPMs. What gauges do I need for a 12V? There is one main/major gauge all diesels need, and that's a Pyrometer/EGT (Exhuast Gas Temperature) gauge. This measures the temperature of your exhaust and gives you an idea of how hard your engine is working and when you need to let off a little. The next gauge most have is a boost gauge, which gives you a measurement of the output of your turbo in psi. This is not as critical gauge as a pyrometer but it does serve some good purposes. Now it is a tossup of whatever other gauges you want. The next level from boost would probably be fuel pressure. It is not that big of problem on 12V trucks but if you want to monitor it and ensure it is running in tip top shape you can get one of them. Not to mention you can tell when your fuel filter is getting clogged. What is the EGT temperature limit? This is a debated topic but the rule of thumb is to not exceed 1050*F. After that is where it gets debatable.. This is what I will say and you can use your own judgement. Aluminum melts at 1220*F, however pistons have oil nozzles under them to constantly keep the piston from getting too hot, but that doesn't mean the piston crown gets cooled that well.. So if you can help it, keep the 1050*F as your limit. If your going up a hill, 1100-1200 might be considered "OK", I would make sure it is followed by a downhill and let off though. The range between 1050* and 1200* is pretty foggy and nobody really knows exactly when the piston will start to melt. However, one thing is for certain, never exceed 1200*F. Your risking everything if you do. What is the normal boost pressure? On a stock truck the turbo is an HX35 or WH1C (94') and the pressure should be between 17-23psi. The 160HP engines will have 17 or so with the 215HP engines having 23. The turbo is only good to 35psi, past that it generates too much heat to be efficient. How much boost pressure will the stock head gasket hold? In stock form it will hold about 40-45psi with some people not having issues up to 50psi. Advancing your timing will lower these limits.. Should I advance my timing and how far can I go? Advancing the timing puts the power curve higher up in the RPM's, so you will have more power in the higher RPM's and less down low. You will gain some mileage too. Keep in mind the more you advance it, the worse it will start. The had gasket is said to be safe up to 16* of timing. Stock is between 12.5 and 13.5. The advanced timing puts more stress on the head gasket so if you are running high boost you may want to reconsider, or do something about the head gasket. How often do I...? Click here for the entire maintenance schedule.

I love the full sweep and full range of numbers. Mine does that 1 2 skip a few crap (200-400-600...) like the 94-97' rpm gauges with their 2 lines between 0 and 1000 so you can measure 333.33333 increments I guess

Them diprocal optix gauges are driving me insane Need to sell all mine and get those :$: Hmm, these nice too http://www.glowshiftdirect.com/Black-7-Color-1500-F-Diesel-Pyrometer-Gauge.aspx

Well seeing as how I still don't see any votes but mine as the 16-20, no your not the youngest.. :biggrin:

Yeah I don't understand why things advance to improve starting, obviously doesn't help matters. The 1st gens also advance timing even more during cold starts, 5* more.. The P7100 doesn't do this so I am always at 16 but he would be around 21 which would explain why it won't start. If you could disable that cold timing advance so it would stay at 16 it would probably start. They say it advances timing during cold weather because it gives the fuel a longer time to burn (since its shot in sooner) because it needs it when everything is cold and this prevents smoking yadda yadda, I got the EXACT opposite! My truck starts worse obviously and smokes like a steam engine. That -2f start, it didn't smoke at all, it never did.. The only thing I can think of happening is the fuel is shot in so early that the piston hasn't come up enough to get much heat going and by the time it finally does get enough heat at the top of the stroke, it lights the fuel off the top of the piston giving horrible start characteristics. With the timing retarded, when the fuel finally shoots out of the injector, there is enough heat that it spontaneously ignites like it is supposed to rather than shooting in fuel then trying to light it off the top of the piston. I think having all the fuel on the top of the piston or wherever it lands also cools it off making it even harder to start. If the air is hot from compression and the injector fires then it will ignite before hitting any metal which will steal heat from the fuel making it impossible to light until the air AND piston wall and piston top reach a higher temp. If they think that advanced timing thing works, they need to advance it after the engine has ran for at least 30 seconds, NOT when it is trying to start! This is the only reason I can come up with for it not starting worth a damn. They say this is the electric cold start timing advance thing so you might unplug it and see what happens. I would think it would have a spring in there to keep it from advancing when unplugged. http://contrails.free.fr/images/Diesel/dsc05348.jpg Hmm, and a pic of one without the cold start thing. http://contrails.free.fr/images/Diesel/dsc05415.jpg

Told you all I would make a movie so here it is. Timing is at around 16.5* and it was 18f this morning. As a reference, heres how it started with the stock 13.5* timing at -2f.

I can't come up with anything else. :confused: Only thing I ever had was a super nintendo

About as make believe as a truck ran by the same thing in a PS2