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Turbo upgrade

As for the offroad fuel: the only difference off off road fuel is there is a red dye added so that it can be tracked as not having road taxes paid.

Both are susceptible to contamination, bugs, etc all the same.
Ds4 specifically could be having a harder time with bad dyed fuel because the dye could add to cloudiness of already bad fuel making it hader for the optic sensor to do it’s job. Another couple of the advantages of the db pumps. No need for clear fuel and ability to handle crappier fuel.
 
I know it’s supposed to be the same thing but usually it worse because the problem we have around here is the majority of the places that sell off road fuel are more rural fuel stations and they store it in above ground tanks and it usually stays in those tanks longer as it’s not sold quick enough and then begins to grow algae.

The last time I bought some for my kubota tractor I noticed more smoke and the engine temp was running higher than when I used on road fuel. I don’t know but they may have treated it with something that caused that. I never looked into. Just bought the green fuel the next time.

Besides all that even the newest fuel systems have a hard time holding up to the current fuel we are dealing with now. On road or off. Side note: the denso HPCR pump holds up well. Injectors not so much
 
Oh, yeah- if it is above ground tank and if you are in a humid climate- those both make it more susceptible.

A really big thing is people don’t turn them in to the authorities. “It’s too much wate of time and no money back to file a report and make 2 or 3 calls.” But if you do it, then share that you did it with others in your town, then when they get screwed, they will do it too. The more the regulating department gets complaints, they will make the suppliers tighten up. I can guarantee the major distribution tanks dont have the problem- they are so large, the fuel always stays too cold to let any algea live.

Who you file complaint with changes by local laws who does it, which finding out is usually the hardest part. But worth it because you can then find out who has the best fuel inyour area and who to avoid.

If you have the ability to store at your location and fill up at home or on the farm (am I causing a micro aggression by assuming you have a farm since you are in Arkansas and own a tractor- haha) if you have a storage tank that keeps the temp low enough, or you treat it and have it in a tank with ZERO uv light (sunlight) then nothing can live in it. Now, if it was alive and you kill it, you need to filter before pumping into your trucks and equipment. Live algea and dead algea both mess up the system the same.

I have helped a few outfits set up systems, an at home version would be: a tank if you need that much and 3 barrel system fixes it. Put barrel #1 in bed of truck and go fill it up add your algeacide now where driving agitation occurs. 1 at a time because more than that requires hazmat license. Come home and siphon/drain (no pumps here) into barrel #2 with the centrifuge plumbed to it. And seal it up so no light can enter snd wait the alloted time for algeacide to kill everything. Most are a couple days max in that volume. Now run it through the cf into barrel #3. Treat and clean the cf for the next use. The cf will Not only remove the bugs, but will remove the far more damaging water in there with any contaminants. Now you can use your pump which we kept uncontaminated to fill the storage tank if needed or just pump from the barrel to your truck and equipment.

For those of you with a forklift or tractor that can unload a full barrel of fuel safely, you only need 2 barrels. Just keep in mind which is the “dirty” barrel and the “clean” one.

Also keep in mind after decontamination of the cf, you can always drain, heat and clean your engine and gear oils to get better life from them, just plan it out.

There was a fleet I worked at that I implemented running all oils on a scheduled through a cf. The fleet was around 80 semi trucks, 4 or 5 forklifts, and a few pickups and cars. The 2 cf system paid for itself in the first 6 months and then some.

Anyways, the centrifuge is a much underused tool to save some money and solve problems. If you can implement one, do so.
 
@Will L. has forgotten more about fuel than I will ever know. However bugs are nasty and modern fuel holds more water to let the expensive SOB's grow better than ever. I link my battle below. In summery get the bad fuel tested and use a treatment that will kill them. It is an infection requiring the proper meds. The fuel can become acidic / corrosive from the bug infection. It's best to throw away bad fuel than try to burn it while ruining an injection system...

Next time you buy fuel anywhere: look on the pump for a weights and measures sticker from the state. CALL THAT NUMBER! Turn the bad fuel in and the State has a "Field Day." They shut down production and delayed deliveries of bad biodiesel till they got it into specs after I turned in the supplier that ruined my injection system.

More than you want to know about bugs in fuel:

https://www.thetruckstop.us/forum/t...ulsd-and-biodiesel-this-can-affect-you.35096/
 
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Haha @Will L. no micro aggression here. The tractor is mainly for mowing and property maintenance I got out of farming a long time ago. Hard to pay the bills with it as least in my part of Arkansas. This is Walmart home office territory so a lot of money around here pushing the farming out

We have a centrifuge setup at work we use for cleaning up failed hydraulic systems after repair. Never used it for fuel but I’m sure it work. We usually do like @WarWagon says and throw it away. Then treat with an algicide and change filters a few times.

That is good advice to report these suppliers. I will probably start suggesting that to customers. Although it won’t help with the money they lost from repairs of the fuel system maybe it will make them feel better. I doubt most of them know that it can be reported.

Wow @WarWagon that was more than I wanted to know about bugs in the fuel but another good read also it does sound like @Will L. Is the one to ask about fuel although I may not understand it all at least we know we have someone that’s got the answers.
 
Save fuel receipts always. Many have gone after the supplier for bad fuel and been made "whole". Gasoline mixed in by foul-up, slug of water... It happens.
 
Will L. said:
@royunion another welcome to the forum. Love to bear others sing the song of fuel preyat the ip. SO MASSIVE an impact, I say it is the most important gauge missing on the dash. Way more than boost, egt, etc. i value it over the voltmeter wether ds4 or a db pump. Between that and a clear ip return line, a person is buying life for the ip and engine.

Although it sounds like you are a proponent of keeping the pmd on the pump (which I disagree) the proper fuel flow helps there too if a person chooses that route. Unfortunately we saw too many pmd failures from heatsoak after the engine is off in the fleets.
Click to expand...

Will L. . . . No NOT so much a proponent of keeping the PMD on the IP, as much as IF you have enough fuel pressure on IP - like 9 and slightly over - it will open the check valve and recirculate fuel so that COOL fuel is always in the IP which then does a good enough job - and sometimes actually better - depending on where one mounts their PMD relocation heat sink - of cooling - which it really does not need "much" of if the fuel pressure is proper.

BUT . . . a poorly placed PMD on a heat sink that is one which cannot cool is worse than leaving it in the stock position with proper fuel re-circulation. On a hot day driving on a hot black asphalt road - under hood temperature are worse than recirculating fuel which a a steady "radiator like" cooling system that is a constant cooling temperature. It takes a lot of heat to raise a tank of fuel's temperature.

The Optical sensor in the IP has a fuel temperature sensor and sadly it is a hidden feature only readable with a scan tool that reaches that extended PCM reading, but the difference is huge when the fuel pressure is higher to the IP because it re-circulates by opening the return check valve.

15 psi at the IP gives the best cooling as the return valve opens around 7 to 9 psi. Sadly when you first put a 15 psi pump on it will act up until the IP and PCM can stabilize with a DS4 IP

A wet immersion rotary lift pump - is the 6.5's best friend - the pump is cooled by fuel for long life and is quite reliable

My engine starts in around 5 seconds - cold or hot - and has 9 psi at the IP at start - and I use a 7 to 9 psi rated pump. I have an electronic sensor driven digital gauge I can rotary switch between transmission line pressure, fuel pressure pre-filter or post filter, and a couple of other pressures not relevant to this discussion

The way the DS4 works is to multiply inlet pressure by stages, and frankly it is designed to need very little throttle "help" from the Fuel Solenoid Driver - everyone knows as the PMD - to pull the throttle open, as the increased pressure from engine RPM to the IP should want to FORCE open the throttle plate - which has a spring on it holding it closed. that is how it idles - by IP pressure forcing past just enough to idle. If there is not enough fuel injection pressure - the PMD creates PWM current to the Fuel Solenoid - which is in the center of the fuel lines at the end of the IP - to hold it and pull it "more" open, and the power transistors which act like switching transistors get the load, overheat and fail if the duty cycle goes on too long with too much frequency (too many times constantly). Solenoids are not meant for 100 percent duty cycles and they heat up and the PMD gets hot trying to hold the power to the Solenoid. That is why with low IP inlet fuel pressure the engine will just "cut off" at idle or when coasting coming back to idle.

During a rebuild if the Fuel Solenoid is not set properly as to distance which is done with a dial indicator reading thousandths that is why the DS4 can do a runaway as to engine speed. On a rebuild it is usually the Fuel Solenoid burnt up and of course the PMD. If it is really bad - the IP internals are scarred up from no lubrication due to low fuel pressures to lubricate the IP

As Will L. emphasized it is the most important thing in the 6.5 fueling system - inlet IP pressure.

Deere65 - if you read this - try to get someone to check your timing (TDC) offset - which should be between -.25 to -.75. You would be shocked to discover how much performance you loose with improper (TDC) offset timing.

Just mechanically putting on a new IP - it will start - and run - but you will not have proper timing until the KOKO procedure is done and many guys who do not have the equipment just leave out that step when they replace a DS4 IP

However, with certain circuits disconnected like the boost waste gate solenoid - this procedure has been known to not work, and also it will not work with DTC's set and present or pending.

The DS4 really cannot do what a Gasoline Engine EGR system does - which is one reason it failed as a path for Electronic Fuel Injection for decreasing Diesel emissions. A Diesel is a throttle-less engine and it only has air - as much as it can get or is forced into the cylinders and then the fuel is injected at (or near) to top of the compression stroke. You need electronic injectors to affect the injection amount by a duty pulse cycle with granularity like a Gas Engine Fuel injection system has.

The Diesel's combustion is more akin to an explosion than a burn - which is why there is a characteristic rattle of valves being slammed shut etc, "that diesel sound" - and the lower quality the fuel the slower it takes to ignite - a.k.a. "ignition delay" which happens with low cetane fuel. And the louder the engine rattle . Sure this happens in milliseconds - but that is why the DS4 tries to change timing to account for different fuel qualities - to try to stay ahead of the ignition delay.

How HOT that explosion is determines the power you get and whether it will burn impurities. That is why CNG and Propane bi-fueling gives such power and are also so dangerous to raise EGT's really fast. Also today - the poor fuel that burns so cool - does not any longer work well - without an additive - to bi-fuel with CNG or Propane because the ignition temperature and delay will not timely light the CNG or Propane. Pure Hydrogen does not have that high ignition temperature problem of CNG or Propane.

The "S" engine EGR system on a GM 6.5 Diesel simply puts "dirty air" in the air being compressed - which is just slightly oil laden air that "might" or might not act as fuel.

Whether you loose power with an EGR system is a function of the quality of the Diesel fuel you are using - with poor fuel that won't light easily - yes you loose power, and may get a little more black smoke from un-burnt fuel, with "hot" high cetane fuel it will simply actually burn the dirty air as fuel.

Admittedly I have an "F" OBDll engine - so I cannot say for sure, but you will get the best performance making sure the timing is correct and fuel pressures are high to the IP inlet. Also mine ran like a bit of a dog with TDC offset at +1.25 and the KOKO procedure corrected that to -.25 without physically moving the IP.

The point is the ECM PCM programming for most all 6.5's is not the best and is really buggy as to how it tries to respond to changes in the engine sensors inputs - as never having really ever been "dialed in" with a lot of experience of the engine family life on the road for only less than ten years and from the change from OBDl then to OBDll and changes in binary code all the way up to 2000 - when it finally became a decent PCM binary.

In the above example - the PCM programming wants to see 180 to 190 as a coolant range and after that it begins to try to change other things - of god only knows what - and event the PCM programmers never really understood things the PCM did. It does the same for fuel temperatures and trans temperature and the list goes on and on in an ugly fashion. One thing it certainly does is decrease fuel - which does not "lean" anything - it results in a decrease in available power due to a lower amount of fuel injected for combustion. It cannot "lean" a throttle-less engine.

All of this is meant to try to save you from damaging your engine. Here is a weird one - if the oil pressure drops below the sensor set mark - the OPS reports - the fuel pump circuit may or may not open to shut off the engine, but usually if you turn of the engine yourself - it may not even physically CRANK again - until you pull the CRANK and GAUGES fuses and simply put them back in. It often will not set a code - but may illuminate the "check gauges light" on the dash.

Deere65 wrote "So I kind of have multiple reasons I’m interested in changing the turbo because doing so really requires new programming which can eliminate a lot of unwanted systems that my truck possess."

The 1994 had early generation buggy PCM code and whether you have the GM upgrades only an appropriate scan tool can tell you. Personally after experiencing that Heath tune come in to the shop that would not accept the KOKO procedure - which I think was the wiring hacking the owner did to disconnect the boost solenoid and not Heath's PCM tune, I upgraded mine by just buying a 2002 PCM complete for a swap in. So the final word is - myself I would not mess with things as little as possible - because you may not know what other Gremlins it will cause in the end.

I believe Quadstar87 ( https://www.thetruckstop.us/forum/members/quadstar87.11829/ ) - a user on this site - might be someone to contact for more ecm / pcm performance timing info
 
Will L. said:
As for the offroad fuel: the only difference off off road fuel is there is a red dye added so that it can be tracked as not having road taxes paid.

Both are susceptible to contamination, bugs, etc all the same.
Ds4 specifically could be having a harder time with bad dyed fuel because the dye could add to cloudiness of already bad fuel making it hader for the optic sensor to do it’s job. Another couple of the advantages of the db pumps. No need for clear fuel and ability to handle crappier fuel.
Click to expand...

This is correct.

Also if again you have low IP pressures to the IP it may FOAM and not fill the upper cavity to where the optical sensor is.

A really dark compendium of fuel additives - like really dark brown - and algae which make also darken it will mess with the optical sensor and it will throw a 370 and 251 code

Trying to run "black diesel" through a DS4 is an impossibility - but of course it will go through the DB2 just fine

The issue for a DS4 is how much dye they use in the off road fuel and how DARK the fuel is. An already dark brown fuel from algae dyed red is really bad.

ALGAE is ugly and will contaminate your entire tank and all the next fuel you put in - but will "first" get trapped in the filter - but if you do not KILL it with algicide of some type it will start to grow in the upper end of the IP and then mess up the optical sensor. A good algicide will kill it and dissolve it and send it to the filter to be caught and you will go through a couple of filters before good flow is restored.

I saw a DS4 opened up and the upper tank area was full of algae and its history before being sent in for rebuild was the engine was throwing persistent 251 and 370 codes.

This post https://www.thetruckstop.us/forum/threads/p0370-p0251-codes-again.32249/ looked like an immediate candidate for the optical sensor troubles - and while it did not show what was the final resolution - algae is small enough to get into the injectors and clog them just enough to spray erratically or cause misfires.

It is safe to buy algae laden fuel so long as you know that is what it is and you should treat ALL bulk bought fuel like it has algae in it and you then filter it first in a buffer algicide treated tank to kill the algae first.

While above ground tanks can be a problem - it is not as much as a problem as not FILLING the tank ALL THE WAY and then putting in algicide to kill algae living up on the sidewalls of the tank. If you cannot fill it all the way - then if you can reach inside spray the walls with gasoline in only a small amount and it will kill the algae.

If you look at the Safety Data Sheets of Killem or Power Service Diesel Kleen you will see that Diethylene glycol monomethyl ether is what is commonly used to kill algae but you will find that 2-Ethylhexyl nitrate (2EHN) both of which are an Alkyl Nitrates kill and inhibit algae - so using a fuel additive religiously is good for that reason also. 2EHN is the main additive to all chemical Cetane enhancers on the market for diesel fuel

Another algicide is Xylene and the family of fuel we call Gasoline - which most safety sheets call "Petroleum Distillates" can be anything from Kerosene to Mineral spirits or "hotter" - like what might be "White Gas" or gasoline. small amounts of gasoline in diesel will kill algae and give it characteristics of better performance.

It is chemistry business and if one does not know chemistry is is all black magic to them. Most any solvent will kill algae, and then off course make sure there ius little or no water left or condensation to let it grow again - or best yet keep the fuel treated at all times with an algicide.

One has to know what they are doing in taking away lubricity with Gasoline and adding BTU per gallon with a hotter - lower flash point solvent like gasoline or Xylene to an additive, but what you are doing in the proper amounts is restoring what the Hydrodesulfurization process steal in making ULSD fuel.

The right mix of two stroke oil, gasoline and a really small amount of 2EHN makes an additive just as good - and even better than any on the market and for pennies on the gallon instead of way more and keeps algae from growing and kills it and cleans the entire system as well over time.

Using a Hydrometer I have seen pump fuel as bad as 38 Cetane - and the 6.5 likes and wants fuel at 44 Cetane and above. (that is what the GM 6.5 Diesel manual says) Chevron makes the best I have seen while other places are a crap shoot what you get. Chevron diesel with an additive runs the engine like a gas engine - and it makes the 6.5 run so quiet - you will cry. (Do not confuse straight API gravity with actual Cetane)

However you cannot measure chemical Cetane improvements that additives do

Chevron is expensive but I use a combination Albertson's gas rewards and Gas Buddy approach to find the cheapest Chevron station for diesel and pay cash with the 20 cents off per gallon I can usually even beat ARCO prices by 10 cents a gallon and run smoother too.
 
Welcome to the forum royunion and Deere65.
I toohad been thinking of installing the ATT system on My 2000 K3500.
At around 70 mph, the tach is not much above the 2000 rpm range. When towing the camper, due to the smaller tires, I run at under 60 mph, not sure the rpms but probably well below 1800. I just do not think the ATT, or any other after market turbo system would do Me much good. I do like to keep the unit in over drive, running in regular D position will increase the rpms but will also decrease the fuel mileage, in My opinion.
I am thinking about the Wicked Wheel and installing that on My stock turbo.
Any opinions on that ?
 
MrMarty51 said:
Welcome to the forum royunion and Deere65.
. . . I am thinking about the Wicked Wheel and installing that on My stock turbo.
Any opinions on that ?
Click to expand...

It will compress more air per rpm of the turbine wheel - yes - but assumes you have a tight turbo waste gate system. On the 6.5 that means a tight vacuum system with a strong vacuum pump to keep the waste gate closed to that higher boost potential

The waste gate natural state is open - remember - vacuum holds it closed

It has to be felt to be believed but - boost means nothing with crappy fuel. the diesel doe snot burn air - it burns fuel - and boost just compresses more air into the cylinder so you can get maximum heat and pressure to light the diesel that is injected.

For instance when I flick on the CNG or Hydrogen - it is like Nitrous for a gas engine - and the boost shoots up to ten - due the PCM it cannot go higher and the waste gate solenoid meters it and the engine takes off like a bat out hell.

On CNG the EGT's will climb, but the power is quite impressive, while on Hydrogen it cools the EGT's

My moral is you can only compress with as much as power is on the exhaust gas side to spin the compressor wheel

A new vacuum pump made a huge difference on mine - even though the old one was working - it had a slight knock meaning the pump cam was wearing down. Now at idle it takes off from a light IN BOOST immediately and drives in 3 to 5 psi at all times until I push it it goes up.

A slight vacuum leak or weak vacuum will let the waste gate open slightly the more exhaust gas pressure hits it and you have no way to tell. Even a slight leak in the waste gate actuator itself will cause the same.

At a couple of hundred dollars the wicked wheel is not a bad investment
 
@royunion

"It is safe to buy algae laden fuel so long as you know that is what it is and you should treat ALL bulk bought fuel like it has algae in it and you then filter it first in a buffer algicide treated tank to kill the algae first. "

It can't hurt to run a biocide now and then, but, what one do you run as there are different ones to kill different bugs. You have to treat a known infection with the proper biocide as the wrong one is in effective, wastes time while the bugs population doubles in 12 hours, and filters/downtime add up.

So saying need good fuel and pressure and then "go buy bug infested crap that used to be fuel" is expensive bad advice. I will give you a pass as "old school" diesel didn't carry and adsorb as much water as the Biodiesel laced ULSD Diesel we deal with today. Today's fuel has enough water in it to allow bugs to grow everywhere rather than "just that the water fuel layer in the bottom of the fuel tank". This change in fuel is why your advice is no longer valid today. Some biocide products on the market are now useless (the ones that treat the water fuel layer only) as well as any steel lined fuel tanks, yellow metal for fuel line parts, etc. You must have a biocide that treats the fuel not just the fuel water layer.

No, "algae laden fuel" is not safe in any way shape or form. The bug infested possibly corrosive fuel is waste oil as it no longer meets spec and damage it can cause is expensive. Fuel polishing services to clean a bug problem up is expensive. (Cheaper to dispose of the small amount of fuel. Big 1000 gal tanks start to make it worth it.) Offhand the bug infested fuel cost me: a $1200 IP rebuild with no core credit, $550 injector set, $150 lift pump, $150 fuel tank (cleaning expensive aux tanks is $200.) and filters by the 6 pack costing $40+ each. Nevermind labor and downtime. Only when the bugs clump together do they plug the filter. We are talking mold, bacteria, yeast that are all smaller than the micron rating of the filter, pass through, and grow everywhere in the system.

As the bad fuel wiped out the IP I started running used IP's to keep rolling. I ran into one IP that TOOK OUT MY ENGINE at 4200+ RPM. Bad fuel could have also corroded and stuck the governor in my original IP. Well it did actually corrode the governor and the rest of the IP but didn't stick. Regardless a bad fuel injection system can wipe out the entire engine. Water in fuel wonking out the timing on Olds 5.7's is known to shatter a cylinder.

IP corroded by Biological growth:
93IP_ate_by_biodiesel_bugs.JPG

Me and my buddy are an experts at dropping fuel tanks of the 1995 burb and 1993 pickup. If I knew now what I know today I would have dosed the system with gasoline to kill everything and thrown the IP away anyway.

HPCR systems are even more sensitive and expensive to fix.
 
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I've thought about doing a replacing my stock unit with a GM8 ( I know, not much of an upgrade) in my 95 burb, it's at 200k with 3:42 gears, has a tune, 4in exht, and I just would like a tad more power/mileage. I don't haul, nothing but kids and dogs, or sometimes the rider on a small trailer. once a year I get 2 yrds of mulch, but other than that, It's a low mile use daily driver, or family across the state hauler every other month.
 
royunion said:
Deere65 - if you read this - try to get someone to check your timing (TDC) offset - which should be between -.25 to -.75. You would be shocked to discover how much performance you loose with improper (TDC) offset timing.

Just mechanically putting on a new IP - it will start - and run - but you will not have proper timing until the KOKO procedure is done and many guys who do not have the equipment just leave out that step when they replace a DS4 IP
Click to expand...
The obd1 does not use the koko procedure. I am able to set and check pump timing use GMTD scantech. I have tried it at -.75 up to -1.94 and it seemed to me to start and run better at -1.94 so that is where it is currently set. If it takes 5 seconds of cranking for your truck to start you may need to check some things out as mine starts within about 2 rotations

So after reading the link @WarWagon posted I see that timing changes when egr is active which seems to me that if my engine is not actually allowing the flow of exhaust gas to the enter the cylinder then it would be having and effect on power and could potentially cause damage to the engine. Now since emissions testing is not required here I am not going to go to the trouble of trying to reinstall the egr system. I think by tuning out the egr would probably be safer for my engine.

Although I am wrong about the engine being leaned during egr. I would like a further explanation on how a diesel can not be leaned or the other extreme rich as the pump can vary how much fuel is injected along with when it injected just like a gas engine. As I understand it a lean or rich condition is determined by the amount of fuel given for the amount of air which could easily be accomplished with the stock programming controlling the turbo. I agree with you @royunion that keeping the stock programming will most likely give me many years of service and be the safest for my engine because that’s what gm wanted but why not unlock what it is safely capable of with the proper use of aftermarket products.

@Pruittx2 I have also wondered if a wicked wheel would a good option for me with a tune which it looks like Quadstar offers a tune to go along with a wicked wheel but I have tried to find someone on the forums that has run one and can offer any info on whether they are worth the money for the 6.5. I haven’t found any support for them. If you have any please share
 
I think it's mostly a matter of terminology and engine types. A lean condition on a diesel simply translates to a colder exhaust temp and less power. It won't physically damage the engine. Conversely too rich is black smoke and higher egts which can be dangerous ,but not normally.
 
Its also because of the way the ignition works, it has different effect on limiting air vs fuel.

Take a carbureted gas engine. The carb will allow 100% of fuel as fast as it can go in. Buy throttling the amount of air getting sucked in the engine speed is controlled. So you make the quantity of fuel match the amount of air going in. Same thing for gas injecected engines. As the air goes in, the komputer meaures air volume and throttle position, then adds the fuel to match the demand.

If you dont have enough gas and you still have high ignition heat from the spark plug, that is too lean of condition and the entire burn of explosion happens while the piston is still on its way up since timing is normally btdc. This is how you hear too lean burns holes in pistons. Now btdc isn’t always the case, but This timing didn’t change to tdc or atdc until focused of maximizing mpg and having the computer able to dave the engine from massive damage. There is always enough air to idle by design, unless you adjust the idle screw to low (cutting air to low).

Diesels dont have sparkplugs, so there is no ignition source to do any damage if there isn’t enough fuel
To burn. And if bare minimum of fuel
Is present but timing too advanced, the compression has to be close enough to tdc that pre detonation is hard to cause under low fuel supply- there is actually only a 3* window in the 21:1 compression,1.5* at 14:1 and 0.75 at 7:1. It is linear.
Thats why the older higher compression diesels are easier to have worse affects from to advanced timing — they simply can ignite the fuel sooner because of higher compression.

A diesel always has max air allowed in. Even turbo or blower shoves in mega quantity of air. The throttle is controlling the amount of fuel going in. Not enough fuel isn’t too lean, it just means lower rpm. Excess of oxygen and not enough fuel is just less power / rpm.
The reason too little boost (oxygen actually) causes black smoke is a ton of fuel is being throttled through the cylinder and with not enough oxygen to burn it, raw fuel is trying to flash off hitting hot metal and leaving the carbon chain unburned. This super hot metal get cold fuel on it then the heat being higher in that spot tips the burn triangle ratio where too little oxygen is just enough and it ignites the fuel in contact with it. So that metal went hot to cold then super hot in a couple nano seconds. It is heat shocking the metal causing fatigue.

People get confused thinking high egt means “x” temperature on the metal and that metal part melts or softens at “y” temperature, so x.5 is ok. No. While somethings could simply melt down in extreme cases, most egt damage is simply metal fatigue being dramatically sped up by temperature swings.

As to a wicked wheel on a k2500, I would vote no. The only reason it is good for the center mount turbo is there are no simple upgrades to better turbos. Complete intake and exhaust plumbing, sometimes body lifts, etc is needed adding a ton of expense. Cheaper is often to mount the turbo below the engine and need a scavange pump for the oil drain. An rv, that could be ok option- but not a 4wd truck that already has an easy access turbo with so many options. Cko hx hybrids for example. If I run out of money, that may be what I do for my center mount- but I can fabricate anything to fit and can do a 2” body lift on the cheap, and have to redo my dog house anyways. I would much rather a happy turbo from a vendor here, but we’ll see about the cash. I already have word out on hummer forum about spacing measurements to see if what I can fit that could be duplicated or as a kit for other hummer owners.
Again, no clue what space is had in the rv in question here.
 
Will L. said:
Its also because of the way the ignition works, it has different effect on limiting air vs fuel.

Take a carbureted gas engine. The carb will allow 100% of fuel as fast as it can go in. Buy throttling the amount of air getting sucked in the engine speed is controlled. So you make the quantity of fuel match the amount of air going in. Same thing for gas injecected engines. As the air goes in, the komputer meaures air volume and throttle position, then adds the fuel to match the demand.

If you dont have enough gas and you still have high ignition heat from the spark plug, that is too lean of condition and the entire burn of explosion happens while the piston is still on its way up since timing is normally btdc. This is how you hear too lean burns holes in pistons. Now btdc isn’t always the case, but This timing didn’t change to tdc or atdc until focused of maximizing mpg and having the computer able to dave the engine from massive damage. There is always enough air to idle by design, unless you adjust the idle screw to low (cutting air to low).

Diesels dont have sparkplugs, so there is no ignition source to do any damage if there isn’t enough fuel
To burn. And if bare minimum of fuel
Is present but timing too advanced, the compression has to be close enough to tdc that pre detonation is hard to cause under low fuel supply- there is actually only a 3* window in the 21:1 compression,1.5* at 14:1 and 0.75 at 7:1. It is linear.
Thats why the older higher compression diesels are easier to have worse affects from to advanced timing — they simply can ignite the fuel sooner because of higher compression.

A diesel always has max air allowed in. Even turbo or blower shoves in mega quantity of air. The throttle is controlling the amount of fuel going in. Not enough fuel isn’t too lean, it just means lower rpm. Excess of oxygen and not enough fuel is just less power / rpm.
The reason too little boost (oxygen actually) causes black smoke is a ton of fuel is being throttled through the cylinder and with not enough oxygen to burn it, raw fuel is trying to flash off hitting hot metal and leaving the carbon chain unburned. This super hot metal get cold fuel on it then the heat being higher in that spot tips the burn triangle ratio where too little oxygen is just enough and it ignites the fuel in contact with it. So that metal went hot to cold then super hot in a couple nano seconds. It is heat shocking the metal causing fatigue.

People get confused thinking high egt means “x” temperature on the metal and that metal part melts or softens at “y” temperature, so x.5 is ok. No. While somethings could simply melt down in extreme cases, most egt damage is simply metal fatigue being dramatically sped up by temperature swings.

As to a wicked wheel on a k2500, I would vote no. The only reason it is good for the center mount turbo is there are no simple upgrades to better turbos. Complete intake and exhaust plumbing, sometimes body lifts, etc is needed adding a ton of expense. Cheaper is often to mount the turbo below the engine and need a scavange pump for the oil drain. An rv, that could be ok option- but not a 4wd truck that already has an easy access turbo with so many options. Cko hx hybrids for example. If I run out of money, that may be what I do for my center mount- but I can fabricate anything to fit and can do a 2” body lift on the cheap, and have to redo my dog house anyways. I would much rather a happy turbo from a vendor here, but we’ll see about the cash. I already have word out on hummer forum about spacing measurements to see if what I can fit that could be duplicated or as a kit for other hummer owners.
Again, no clue what space is had in the rv in question here.
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Thanks Will, you’re a wealth of knowledge.
 
Thats right it’s the basics. Now I feel like I should go back to school. Especially now where there are Diesel engines using air throttles and exhaust throttles.

That would be awesome if you could get a kit built for the center mount turbo guys to give them more options. I’ve seen a couple hummers for sale around here lately. All out of my price range but I’ve always thought it would be fun to own one.

I’ve got a buddy at work that has a wicked wheel on his 7.3 and swears by it. Most of the info I found on the wicked wheel says that it started out as a fix for the fords where the turbo would surge and wasn’t ever really for performance so that always made me wonder if it was worth anything on the 6.5.

So I guess what I’m looking at for my truck as it is would be leave it and just go with a better tune or go with the ATT and probably not see any gain with daily driving because of low rpm but towing would be where I see the gain as long as I run it in lower gears. The hx turbo would probably be about the same but I my see higher egt’s with it over the Att. Plus make darn sure the fuel system is up to the task before any upgrade goes in place. I think I’m getting a grasp on all the great info here
 
Something to keep in mind is the ATT is the only turbo that wont benefit from an inner cooler. They help so much that you can’t buy any newer diesel that doesn’t use one stock afaik. There are lots of options for that.
 
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