ISX

Well the HX35 will go up to 35psi and still be fine, after that it becomes too small of turbo and just creates heat because it has to turn so fast to get anything over 35. The wastegate opens at ~20psi stock and the boost elbow keeps it from opening until whatever you set it at. The wastegate really is wasteful. It dumps pressure so you end up stopping at a lower boost pressure. If you were to plug it, you would get max efficiency out of the turbo until you went over 35psi. The wastegate dumps pressure out so it doesn't drive the turbine, which is wasteful. I made a really rigged up wastegate actuator that will not open the wastegate until it hits 35psi and my EGT's are lower and I have more power because I am building more boost sooner. Before, I would have to get to the wastegate opening pressure, then outflow the wastegate to go any higher. If I floored it I could get to 30 eventually. But with my wastegate actuator, I can hit 30 at 3/4 throttle because I am not having to work against the wastegate. That answer your question?

I'm actually at an all time high on percentage over him

Yeah you are basically only measuring part of the blow by since the .221 thing relieves part of it. If that outlet is not there, there is nothing stopping it from either blowing out the dipstick or blowing all your water out. What you are building is a crude manometer.

I actually did this but you MUST use the "T" on the blowby tube with a .221" outlet. If you don't it will push all the water out of the blow by tube. I didn't read the T part Oh and if you put your finger over the blow by tube to keep the water from coming out, it will just push the pressure out of the dipstick, and since the dipstick is in a tank of oil, the principles of hydraulics will push oil out of the dipstick. :banghead: So don't skip the T haha.

Your right there. I can only get 5psi if I redline my truck in neutral. Under a load is a different story. You do need flow and you get flow from a lot of fuel being burned. I am not sure if the guy at the stoplight was building any boost, I just know it was screaming so it is something to think about. I am not sure it is really back pressure that does it the more that I think about it. I think it is more the fact that he is just chopping the same air rather than the back pressure doing it. The turbine needs to spin as fast as possible to produce boost and I think back pressure would hinder this. So I'm going to say the muffler produces less boost. --- Update to the previous post... Found this on another site. I will break it up since they have it as one huge run on paragraph. VOLUMETRIC EFFICIENCY AND BACKPRESSURE Although the turbine recovers wasted exhaust gas energy from the expansion of the hot exhaust gas, the kinetic energy of the flowing exhaust gas and the acoustic energy of the exhaust gas, the working turbine also causes an increase in exhaust gas backpressure. This increase in backpressure can reduce the engine's volumetric efficiency. A typical, streetable turbo system has more exhaust backpressure than boost pressure and the power gains from such systems are due to the increase in the density of the intake charger, not due to increases in volumetric efficiency. (Volumetric efficiency, if you don't remember, is the volume of intake charge inhaled during the intake stroke vs. the actual displacement of the cylinder. VE is expressed as a percentage; the larger the VE, the better.) Backpressure is higher than boost pressure because the smaller turbine housings and turbine wheels used to ensure a quick spool-up time also, by nature, restrict the exhaust flow. We will explain the mechanics of this in more detail a little later. Racing turbos, the latest generation of medium-sized turbos and turbochargers for engines where throttle response is not much of an issue (like fixed industrial engines, long haul trucks and aircraft), have free-flowing turbines that have less exhaust pressure than intake pressure. Engines using these turbos often do have improved volumetric efficiency. This condition, where boost is higher than backpressure, is called crossover and crossover is what ever turbo system designer strives for. In crossover, VE percentages as high as 110 percent are not unheard of. Unfortunately, some of the design features that can create a free-flowing turbo can also contribute to turbo lag, something that is not desirable in a street-driven car that needs a wide dynamic power band. Excessive backpressure is hard to manage in a boosted four-stroke engine. Excess backpressure causes what is known as reversion. Reversion is when hot exhaust gas gets pumped backwards into the engine during the overlap period. Reversion can cause the engines internals to get excessively hot as cross flow of the cool intake charge during overlap is one of the ways an engine cools its self internally. Hot internal parts can trigger uncontrolled combustion and engine-destroying detonation. Because of this, it is sometimes not a good idea to really crank the boost on an engine that has a small, high-backpressure turbo - in other words, the kind of turbo that usually comes on a factory turbo car. This is a good reason not to go crazy with a boost controller on a factory-equipped turbo car. A little more boost, perhaps 4 to 5 psi might be tolerated, but trying for 20psi could be flirting with disaster. On small turbo cars with a lot of backpressure, camshaft overlap should be kept to a minimum. This means that the stock cam usually will work best. To deal with the problems associated with backpressure and reversion, the engine's tuning must also be compromised with richer mixtures and more retarded timing than what would normally be optimal for the best power. Even on full race turbocharged cars with low backpressure turbos, camshaft overlap should be several degrees less with more lobe separation angle than on an equivalent naturally aspirated engine, unless physical measurements indicate that the engine is in crossover in the engine's operational range. Because of backpressure and VE issues, the correct turbo size for the application is very important when designing a turbo system. A small, quick-spooling turbo can be restrictive, causing a great deal of backpressure and reducing VE at higher rpm. This means that small turbos should be limited to lower boost levels. A big, free-flowing turbo can be laggy and unresponsive, making it unpleasant for street driving but producing awesome power at higher rpm. To combat high backpressure and possible reversion, the compromised tuning needed to prevent destruction with an overboosted small turbo will also reduce power. If a small turbocharger is running backpressure to boost ratio of more than about 1.8:1, a supercharger has a good chance of performing better. Fortunately, it is easy to design a reasonable responsive, powerful turbo system with a ratio of less than this.

I'm curious here. How is it that it can act dead for a few minutes, and then all of a sudden it runs like normal, and that is a symptom of a dead pump? I think that is what the consensus usually says but I just don't get how a pump that is dead for a few minutes and fine for the rest of the while is deemed as being dead.

I think there are 2 variables here. A while back I was at a stoplight and along came another cummins with his exhaust brake on, well the turbo was screaming. Have you ever put your hand over one side of a little fan and watched it speed up? Same principle, I think. So back pressure allows it to speed up because it just spins the same air around itself without having to chop up new air. Since the compressor is on the same shaft, it would be producing more boost. But that's where variable #2 comes in. What good is boost when you have back pressure so the flow isn't there? It just stops flowing and hence why it was braking the engine. So although some back pressure might spin the turbo faster, I am not sure it is really beneficial in the end, because of variable #2.

You got a dozer there, strap it on and take it off.. I use my front end loader for all of that kind of thing. If you saw how I did things, a person in a wheelchair could repeat my doings lol.

I would check all those fancy hose connections that you have to have a special tool to remove. My ford liked to rattle those around.

So when your gauge messes up and you run out of fuel you can't bleed it That is one heck of a set. Just looking at it I thought it seemed like I was looking at some optical illusion from there being so many. That squares away the main tools, well actually I haven't stuck any in yet but I was wondering more what else as in specialty tools.. Like umm, hmm, gear puller.. Probably can't fit that in there but specialty stuff like that. I'll probably throw a feeler gauge in and maybe some calipers along with all my electrical crap but I can't think of anything else. I got a really bright LED light so we're good there. Hmmm, lock tite, haynes manual. --- Update to the previous post... I had no idea I could fit all this in there. I thought only 2/3 of all that was going to fit. I think Flman's organization on the sprinter must have rubbed off I took it down the road to see how awful it was and when you hear me open the socket drawer you hear all the chinging, well that was all I really heard and that was in our driveway full of braking bumps. It was the socket wrench and all those extensions so I stuck them all together and stuck it between one of the socket sets, problem solved. Believe it or not, turning or braking didn't make a sound. Think I packed it good and tight so it won't slide around. So as long as I can make it out of the driveway, I'm good to go http-~~-//www.youtube.com/watch?v=AFRJFRlNNYY

I know one guy who has a HUGEEE travel trailer to the point that he gave up his 3500 dmax and bought a kodiak, obviously he has a huge fuel bill to go along with it. But he put a camper shell on the bed and he said that gained him a bunch of mileage. Anything to make it a little more aerodynamic. Without the shell, the wind goes back down and has to hit the front of the trailer, with it, it only has to plow through whatever is over the trucks height.

Like I ever need to slow down.. I got the fuel pressure fixed so now it's even faster, have to take you for a ride lol.

What happened there? I assume there is some historical significance to that place. The only thing I found when searching for Becker Hollow is that the trail is realllly steep

You might be right I'm not sure. My theory is pretty wild Probably thinking about it too much. Either way everyone that has this issue upgraded their injectors and beefed up the trans..

I need a 100 hour a week job in or something. Been so bored I have just been out staring at my truck making it more customized each day. A week ago I took the back seat out. I have had so much crap on it for a long time that I just cleaned it all out and threw the seat in the attic. The roominess was nice. For some reason we have a lot of toolboxes around the house so I eventually decided to try one out. The viable ones were either the one I used or one that was a little taller with maybe 3 more drawers. That one wouldn't work since the top had to open to open the drawers and I would have had to put the box 3-4" away from the back of the cab, which then I probably couldn't open the drawers very far. So I decided on this little one which might be better since it has a deep drawer which the other didn't have. Got it centered in perfectly and it sits about 1/4" from the back of the cab so they wouldn't rattle each other. Put some self tapping screws in and now it's solid as a rock. The hardest part which maybe you guys can help me with is deciding which tools to put in it. Socketwise, my 1/4" will go up to 14mm-9/16" so I think I will just throw in a 1/2" set that starts at 15mm-5/8" and goes from there. I will probably put a good amount of wrenches in it. That leaves pliers which can probably fit in with the sockets. Screwdrivers. What else would you guys have in it? As for application, I just want to be able to work on anything on my truck in the middle of nowhere.

Just turn all the vent controls to off. If you want to take the alternator out of the equation, just pull the 120AMP fuse. You have to take the 2 screws out on either side of it, it doesn't actually "pull out" it is bolted in. All of that will be hot so be aware of that. I don't think you are supposed to run the alternator without a load though. You gotta be kidding me! Then that explains my theory perfectly. Let me make it more understandable first. I will assume the new injectors have the same pop off pressure, just bigger holes in the nozzle. So bigger holes mean more flow. Now lets look at the idle operation of an automatic. It is still fueling the same amount it was with stock injectors, but these flow and are bigger so it would be like trying to run an uh, ISX, with my 5.9 lift pump (really extreme I know but you get the point). So it needs a lot of fuel to run, but I am not supplying it with much. In other words, the injector isn't popping off enough at idle. So you put it in D, it is underpowered from the lack of fuel and dies. Well that's one theory but now what do winter and summer fuel have to do with it. Well if you think about the big injectors, they flow so much and yet only have barely enough flow to run them at idle. So when they do pop, they shoot the fuel out very fast, stock injectors were slower because the holes were smaller (like different orifices). Since winter fuel has high cetane, it burns up quickly. With a very short but large flow injection, the fuel would blow up instantly, to the point of burning up completely way before it should. So the summer fuel, having low cetane, took longer to light and was able to stay burning up to a more efficient duration. Now SASQCH didn't have any symptoms, the load instantly killed it. But after seeing Johns just peter out and die, that makes me think it is not getting enough fuel or an inefficient burn duration. Maybe this whole theory is too far out to be true I kept trying to understand why the thing wasn't compensating but you said the auto's don't compensate, just like mine, like it just goes back until it hits a screw (computerized screw lol). So now it really has me wondering. Hmm, are the injector internals also bigger? So if it reaches pop off, it expels all that fuel, then has to fill alllll that space again, and maybe at idle it isn't able to fill that space so it doesn't even get the next pop injection squeezed off.

So I changed out the fuel filter and cleaned out the prefilter. Problem solved. I didn't really see it go over 35PSI before, now it will get to 45. I read that you don't want to ever go over 45 so I am at the limit and don't think I will do anything about it since the spring will wear and then it will be lower. It actually only hits that pressure when you are high in the RPM's and let off, since it isn't burning any fuel and the pump is still pumping really good, the pressure just builds up. I think it might be an overflow valve inlet size issue that causes it not to relieve all the pressure fast enough. On this site http://torkteknology.com/products.php?product=TORK-TEK-CUMMINS--ADJUSTABLE-OVERFLOW-VALVE-OFV040 it says they went to a smaller inlet size to make the overflow valve last longer. The good thing is that when I floor it, it only drops to 35. I am going to have to change up the article I made so it includes all of this, including that site for the fancy valve that supposedly is the cats meow.

I am thinking the voltage drops somehow when you put it in D and for that second of engagement it kills the VP. But I am not sure on that. Someone on another forum was talking about increasing idle on the VP and I think they just ran into a wall. I don't think it's possible. Maybe change the ECM programming or something. I'd like to see what the voltage does first. Might end up with another clue on the problem.

If you have some kind of voltmeter (does that chip on your dash have one somewhere? I know scangauge does) you can see if it goes over 13 after it starts. Mine is pretty instant. Turn your blower motor and brights on and that will give you a ~50 amp load and you should still be over 13v. The gauge on the instrument panel is pretty crappy but if it stays over 14v (on the gauge) the whole time then chances are the alternator is fine. A voltmeter would confirm it more though. I wonder if we could tap into the VP power and see what voltage it has the entire time. Do the same thing on the ECM.

I've cheaped out a few times and just found myself going back to buy it. That stuff is like 4x more than RTV but it's worth it. If you don't waste the stuff it actually goes a long ways.

Yeah I'm just thinking the fuel filter isn't letting it flow. It can let it flow down lower but when it needs a lot of flow (floored) it just won't let that kind of volume pass through. Have to see tomorrow. I've gone a long time on this fuel filter lol. Long enough that I don't want to talk about it I might drill and tap the filter housing like it is stock on 24v's so then I have some prefilter test ports.

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Generally, you tighten the bolts in the center and work your way out. So get them all a little tight, then tighten the top middle then bottom middle, then top left of middle then bottom right of middle... Just keep going top to bottom and left and right. Its the same way on things as thin as oil pans or as thick as the cylinder head. Here is an oil pan example so you see what I mean. As for gaskets with or without RTV, I think the application has a lot to do with it. Oil pans are warped a lot of times in between bolts so I always get some "The Right Stuff" and put thin coat on both sides of the gasket. As for the oil cooler, it is thicker so I don't think would need any kind of sealant. That's my A *thin* coat of RTV like Blueox01 said couldn't hurt, but I think making sure the mating surfaces are perfect would allow for just the gasket without RTV. Did it leak out of the fiber or metal gasket?

I made an article on fuel pressure and am having some issues. I think I know what the problem is but I figured I would keep tabs of the problem on a thread so someone else can learn too. In that article, my fuel pressure tops out at ~22psi. It is supposed to "never fall under 25psi under a load" so the fact that it was just idling and couldn't get to it (even when at 2500RPM) tells me there is something going on. After restricting the return line, pressure rose and I stopped restricting at 30psi and it remained at that pressure throughout the entire RPM range. Ok, bad overflow valve. Got the new one in today and stuck it in. Pressure is now normal. 17-22psi idle, 25-35psi at 2500RPM. After getting onto the road, it was a different story. Pressure was fine until you floored it and it would reach a low of ~22psi. The overflow valve works fine, so the next thing in line is filtering. I haven't touched them in a while and I have a feeling they are not going to be pretty. After changing the main filter and cleaning the fuel heater prefilter, I will test again. If no change, we will move on to the lift pump. Should be interesting. This shows that pressure alone means nothing. We need flow too. All the test procedures say to run all the tests idling and mine is perfect, but driving needs flow. So they need to add it to their procedure. I will get the filter tomorrow and see what happens. If nothing, I will try and dig up some lift pump diagnostics. I ran a flow test at idle a couple weeks ago and got I think it was 36GPH. The lift pump is mechanical so the flow increases as RPM increases. Naturally, idle RPM will have a lower flow.

I'll show you how it's done John