89ROC-Z

iTrader: (11)

Should of posted this earlier but it just popped in my head again.

Last weekend NTPA had their tractor pull nationals where i live. Up to 4 turbos on the tractors and the announcer said they push 200 psi or more

So i of course go to the pits and ask around what turbos they're running and what they do for iat's. I suspected some huge custom billet turbos... but was dead wrong lol. One guy had 4 holsets on his IH, said they where like H5?? don't remember exactly what he said. Two headers off the motor, each one going to 2 turbo's in the standared compound fashion. It blew my mind that these turbos that you can get off ebay can make that much boost!

For air temps he's running 22 nozzles and going through 3 gallons of water in 320 feet and around 4 gallons of diesel

I know its not lsx related but pretty cool nonetheless

ttranssam

iTrader: (10)

lol that is crazy badass. i use to go to the tractor pulls. i love the cloud of black smoke and the sound of the turbos as they let off the throttle...

mgroshong

diesel guys are crazy end of story, hahaha

sbcgenII

iTrader: (1)

Wonder what the backpressure is...

darkhorizon

Backpressure x2 lol.

I imagine these are compounded 4x, which means each turbo is only doing 50psi

cbr600rx7

iTrader: (12)

^ agreed. I think the most i have seen on a single is about 80 psi and that was on a pulling truck with a cummins. However with that being said there are guys out there running closs to 100 psi on compound set ups on the street. Now thats freaking crazy!

BadgeZ28

iTrader: (28)

That is a crazy amount of boost considering a 7000 HP fuel dragster sees 55 pounds on a run.

NemeSS

iTrader: (127)

holset makes quality turbos

RCC

Before I started playing with my vette. I had a fairly quick diesel I ran on the street. Truck had holsets on it and regularly seen 100psi. It was nothing like the tractor pullers but fun nonetheless. It was big learning experience going to gas motors and turbos, my vette made max power at 18-20 psi and I launched the truck at 30psi.

Dyno vid at 60-70 psi

http://www.relentlessdiesel.com/medi...C%201132HP.wmv

Track video

http://www.relentlessdiesel.com/medi...0atbaytown.wmv

Zombie

iTrader: (2)

Boost doesn't make power on diesels, it just cools the charge so you can add more fuel without melting stuff. Totally different in the way it works compared to gas motors.

RCC

Are you serious? Turbos on diesel work exactly the same as on a gas motor. They add air density that makes more power. Boost doesnt cool anything, if anything it is the heat generator that melts parts.

Zombie

iTrader: (2)

yes, I'm serious. Add more fuel on a gas motor, what happens? You lose power and EGT's drop. Add more fuel on a diesel motor, what happens? You make more power and EGT's rise.

Add more air on a gas motor without adding fuel and you'll 1st raise the combustion temps, then start losing power because there isn't enough fuel. Do the same to a diesel and all you get is cooler combustion temps and less soot.

The do work the same in their function of adding more air to the mixture, but it serves different purposes.

mgroshong

Idiot you is one.

But seriously you should go read up on diesels more. for one soot is to much fool aka not enough air and yeah egt's are higher when running richer in a diesel as your not burning the fuel. So this means it goes straight through the engine and into the exhaust hence soot/smoke.

I'm not going to continue to explain how wrong you are in thinking boost cools ****.

HAHA boost doesn't make power it cools.

cbr600rx7

iTrader: (12)

^ He is right on this one. The turbo adds air so you are able to add more fuel to make power. It also loads more cool air into the engine reducing EGT's on diesels. This is why older NA diesel will run 200-300 degrees cooler on exhaust gas temps when you add a turbocharger to them. Of course they will not start making any extra power untill you start turning up your injection pump to push more fuel into the engine then they just start creeping right back up.

topend

mgroshong is right about diesels

more air plus more fuel = more power

6.0ltrS10

iTrader: (2)

I cool my house with compond turbos but I have to shut them off to open the door. LOL

Zombie

iTrader: (2)

Yes, but what happens on a diesel if you just add air and no additional fuel? Combustion temps go up or down? Power goes up or down? It won't blow up like a gas motor would under the same circumstances would it?

What about putting 200HP worth of n2o on a stock diesel with no additional fuel, will you gain close to 200 hp? Will it blow up?
What happens if you blow 300 degree air into 1600 degree air, will the 1600 degree air get hotter?
What happens to the temperature if you keep adding more diesel to the combustion process without supplying more oxygen?
How do you correct what happens?
How do you throttle the power a diesel engine makes, do you vary the amount of air coming in with a throttle body or the amount of fuel (air fuel ratio).
What is the operating air fuel ratio range of a diesel at idle and WOT?

Feel free to continue taking my original post out of the context I intended, but only after answering the questions I just asked.

cbr600rx7

iTrader: (12)

You can not run a diesel lean.

Adding air with out fuel will not add power to a diesel.

If you keep adding fuel with out adding air you will get smoke (not burning all your fuel and egt's will start going up).

Diesels are contolled by the injection pump and the amount of fuel that is added to the engine, NOT by controlling air flow with a throttle body like a gas motor.

Diesels dont have a operating AFR. If you add too much fuel and dont have enough air to burn it you start blowing black smoke which is not a good thing since its fuel being wasted and it makes you EGT's go sky high.

If your blowing 300 degree air into 1600 degree air of course its going to lower your overall temp.

I think every one is on the same page here. We are just trying to say the same things diffrent ways.

Zombie

iTrader: (2)

I don't think everyone is (you seem to understand what I was stating), most don't seem to understand why the extra air is needed and what it does for the combustion process. It's very different than a gas motor and judging by the childish comments in this thread many don't understand that, one guy even thinks boost melts the engine.

Maybe just saying it cools and just leaving at that left it too open. The added air is used to lean out the mixture to keep the combustion process under control. If the combustion process is running too hot due to being too rich, you add more air (boost in this discussion) to cool it off and make more power through a more complete burn.

Running high boost on a diesel vs running high boost on a gas motor are very different scenarios. They both need the extra air, but for different reasons.

Diesel: Add air to match your fuel, power regulated by amount of fuel delivered.
Gas: Add fuel to match your air, power regualted by amount of air delivered.

89ROC-Z

iTrader: (11)

Oh my what happened in here!

Zombie seems to know whats going on, as does cbr600. To shut off a diesel all you need to do is stop air from entering the motor. Add power by simply turning up the injector pump (already tore out a planetary on a little 7710 ford lol). I would THINK adding air will allow you to burn more fuel, simply put.

I'm no expert on diesel combustion, but i guarantee i've put more hours in them than all you lol.