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Discussion Starter · #1 ·
i'm new to diesel's so it's a whole new ballgame for me. i'm used to tuning turbo gas powered cars where i add air, and then add fuel to match.
it seems on a diesel, all the air is already there, and we just add more and more fuel to make mroe power. ok...
so, what happens if i stick some big injecftors in? does it just run really rich all the time, or what? what controls the amount of fuel going into the injectors and makes sure that the right amount is being injected under all conditions?
in a gas turbo car, big injectors willmake it run like crap (rich) unless you get a piggyback of some sort to modify the airflow signal to amke the ecu give the injectors a shorter pulse width.

regarding EGT's.... i'm used to having too much air and not enough fuel making them too high. is it the same on a diesel?

why would egt's get too high if i had a tuner of some sort? don't the tuners' just add fuel? how could there not be enough fuel to make EGTs too high if i'm just adding fuel?
i have more questions, but i'll start with these.
 

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SootCloudMaker3
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High EGT's are bad or hard on the motor. Pistons will start to melt i think around 1350 i believe. Someone can correct me if im wrong but that is for a period of time. If you dont have enough air and too much fuel the ingnition in the cylinder is too hot due to to much fuel. Diesel burns hotter than gas.

Like i said someone can correct me if im wrong. That was just a stab.
 

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That is a safe temperature.

High EGT's are bad or hard on the motor. Pistons will start to melt i think around 1350 i believe. Someone can correct me if im wrong but that is for a period of time. If you dont have enough air and too much fuel the ingnition in the cylinder is too hot due to to much fuel. Diesel burns hotter than gas.

Like i said someone can correct me if im wrong. That was just a stab.
1350 is a safe temerature as long as you do not stay there for long. I pull my truck and it sits at about 1400 under a load and it's ok as long as it is not for prolonged periods of time.
 

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i'm new to diesel's so it's a whole new ballgame for me. i'm used to tuning turbo gas powered cars where i add air, and then add fuel to match.
it seems on a diesel, all the air is already there, and we just add more and more fuel to make mroe power. ok...
so, what happens if i stick some big injecftors in? does it just run really rich all the time, or what? what controls the amount of fuel going into the injectors and makes sure that the right amount is being injected under all conditions?
in a gas turbo car, big injectors willmake it run like crap (rich) unless you get a piggyback of some sort to modify the airflow signal to amke the ecu give the injectors a shorter pulse width.

regarding EGT's.... i'm used to having too much air and not enough fuel making them too high. is it the same on a diesel?

why would egt's get too high if i had a tuner of some sort? don't the tuners' just add fuel? how could there not be enough fuel to make EGTs too high if i'm just adding fuel?
i have more questions, but i'll start with these.
Terminaltsi a performance chip adds fuel in the cylinder. as you know in a diesel, compression causes the truck to operate. if more fuel is in the cylinder exploding at one time, it causes higher egt's.

Also if you add fuel to a diesel is is best to add more air also so that you get the maximum horsepower out of your truck.
 

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On a Diesel, forget about stoichiometry. Forgeddubout it. Don't even think about it beyond "fuel needs air, air needs fuel". All running rich does is make smoke, and it's basically running lean whenever it's not smoking black.

Added fuel increases EGT's in two ways.

The first way is through "afterburning", which is where the fuel doesn't have time to finish burning in the combustion chamber and continues burning in the manifold and turbocharger. That might not really be overheating anything in and out of itself, but it heats up your pyrometer probe quickly. Afterburning is the phenomenon whereby added fuel can increase EGT's even if not adding any power...

The second way is by pushing the turbocharger out of its effective range. When you add more fuel, it burns, making more heat. The turbocharger takes that heat and turns it into boost pressure, which allows you to burn more fuel and make more heat. The cycle will go on forever, but small turbochargers start acting as choke points after a given boost level. A stock turbocharger could be making 140 PSI of back pressure when it's making 50 PSI of boost. At that point "it's only moving hot air"; you just don't have a free-flowing enough exhaust turbine to get rid of the added heat you're burning.
 

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Discussion Starter · #6 ·
ok, so too much fuel makes EGt's high. got it. that's weird to me, but i was a gas guy for years, so i'll get used to it. after a while of tuning a certain kind of vehicle, y ou look at gauges and immediatley know what's going on, i'm going to have to retrain myself for my truck!

so what about the injectors? can i just buy some bigger ones and stick them in? do i need a bigger/better fuel pump first? will they make me too rich? if so, how do i lean it out some?
 

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Forgeddabout "rich" and "lean", man. :T:
Foreign concepts.


Injectors give you fuel. Fuel affects you according to a ratio between power and smoke/EGT's. Some of the added fuel gives power, the rest gives smoke/EGT's.

With the stock turbocharger, additional fuel will add a little bit of power and a lot of smoke/EGT's. With a better turbocharger, you will get relatively more power and less smoke/EGT's.

Now, the stock injectors can flow much more fuel than stock with pump tweaks or pump programming. You can get to the stock turbo's limiting point on stock injectors.

And in most cases, EGT's and smoke are plenty controllable with the fuel pedal. If you put big injectors into a truck with an inadequate turbocharger, nothing is preventing you from giving it just as much fuel as the turbocharger can handle. That's where you start driving by the pyrometer and boost gauges.
 

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Discussion Starter · #8 ·
ok so basically, i can max out the stock turbo on stock injectors with the right electronic 'boxes".
at this point i don't know if i really want to go to a larger turbo or injectors, i'm trying to keep this thing from becoming a huge money pit like every car i've ever owned was!
i know the edge EZ is just a basic add on, i guess i should look at a more expensive unit with more features and tunability in the future.

would a FASS setup or similar be a good thing to add at this point?
 

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First...GAUGES!

Second...fuel pump liek the Fass setup.

Third..you are going to need a clutch. With stock, you can only add a few horsepower...

Fourth...what year do you have???? Based on that, go with another chip/programmer...

But like Begle said, you can keep throwing fuel at it, and keep making power...and he shoudl have everythign else cleared up for ya :thumbsup.
 

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i'm trying to keep this thing from becoming a huge money pit like every car i've ever owned was!

would a FASS setup or similar be a good thing to add at this point?
HA!! good luck with that one...:w:
You wont need Fass now, but it wouldnt hurt, its something to be done in the near future, also I am assuming your truck is a 24v with your talk of a box. Smarty is good for electronics on a common rail(03 and up) and I've heard the adrenaline is good for the 98.5-02. The Edge Juice is a good chip, you can get the attitude monitor also which has built in gauges. With programming, your stock injectors and turbo can work together and get lots of power. If you do go big with power dont forget that tranny.
 

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i'm trying to keep this thing from becoming a huge money pit like every car i've ever owned was!
:rof:rof:rof:lol3::lol3::lol3:

Those other cars were a drop in the ocean, but if it makes you feel any better this one is actually worth it :thumbsup
 

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Discussion Starter · #12 ·
First...GAUGES!

Second...fuel pump liek the Fass setup.

Third..you are going to need a clutch. With stock, you can only add a few horsepower...

Fourth...what year do you have???? Based on that, go with another chip/programmer...

But like Begle said, you can keep throwing fuel at it, and keep making power...and he shoudl have everythign else cleared up for ya :thumbsup.
yes gauges are my next purchase for the truck, i like to know what's going on.

FASS seems like a good idea whether i go for more power or just want it to be reliable.

clutch, i'll keep this one until it's done. for all i know, it's already been replaced, as the truck had the edge ez on it when i bought it.

it's a 99.


HA!! good luck with that one...:w:
You wont need Fass now, but it wouldnt hurt, its something to be done in the near future, also I am assuming your truck is a 24v with your talk of a box. Smarty is good for electronics on a common rail(03 and up) and I've heard the adrenaline is good for the 98.5-02. The Edge Juice is a good chip, you can get the attitude monitor also which has built in gauges. With programming, your stock injectors and turbo can work together and get lots of power. If you do go big with power dont forget that tranny.
yes it's a 24v and a manual trans, so at most i'll need a clutch if it hasn't already been replaced.
:rof:rof:rof:lol3::lol3::lol3:

Those other cars were a drop in the ocean, but if it makes you feel any better this one is actually worth it :thumbsup
haha, i don't know, i dont' really think i need this thing running 11's like some of my cars did! although i do have to agree, anything i do to the truck, feels like it's worth every penny. i've had it for 4 days now and it's already one of my most favorite vehicles i've ever owned, and i've had plenty! i plan on keeping this thing a long long time.
 

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haha, i don't know, i dont' really think i need this thing running 11's like some of my cars did! although i do have to agree, anything i do to the truck, feels like it's worth every penny. i've had it for 4 days now and it's already one of my most favorite vehicles i've ever owned, and i've had plenty! i plan on keeping this thing a long long time.


NO body really NEEDS to run 11's BUT its really fun to get there!!!:thumbsup
 

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Discussion Starter · #14 ·
you're right about that. it's really fun for 11 seconds!
 
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