mkiv_tt

I dont know much about deisel motors. Im into the foreign turbo cars (plese dont flame me to hard

Im trying to help out a friend of mine with his turbo deisel ram

I think its the 98-00 version. He said it has 235hp

What is the stock boost on the stock turbo?
How much boost can you run on stock fuel system safely?
What kind of boost controllers do you use? MBC's, or EBC's?

He wants to get a little extra power out of his truck. His mods that i know of are stacks.

Thanks

Stamey

Stock boost will be about 19 psi.
The fuel system will handle varying injectors, but they don't relate directly to how much boost the fuell systel will handle. You have to worry about if the fuel pump can maintain fuel pressure at WOT with the injectors/box you have on the engine.
The boost will be determined by the injectors/box you have on the engine, and the wastegate mods you do.

What you have to worry about as far as boost goes is your head gasket. Stock head gaskets can take as much as 70 psi of boost, if you retorque the head bolts, and don't run high boost until the engine is at full operating temperature. Note: this number is not set in stone, but I have heard it is a pretty reliable number to go by.
Once you get over 70 psi you will need to O-ring the head.

The stock turbo is not good for more than about 35 PSI, but this number can be lower, depending on which stock turbo you have.

Chris

mkiv_tt

So for boost control do you just put different actuators on that have stiffer springs? Does anyone run just plain old manual boost controllers?

How much boost can you run safely on the stock fuel system?

When you say it can handle 70 psi are you talking about cylinder compression?

How do you tell what turbo is on the car? Do they come with different size turbos on each model?

What is the "injectors/box"?

What is the efficiency range on the turbo?

Thanks for the help

Stamey

With the stock turbo, depending on which one you have, you can do *some* adjustment to the wastegate, with a vacuum elbow or with a turnbuckle. Some people just eliminate the wastegate altogether.
As I said before, the boost is not dependent on the fuel system. The fuel system just needs to have pressure no matter what rate you are dumping fuel into the engine.
70 PSI is what amount of boost the turbo is pushing into the engine, measured somewhere in the intake system, after the turbo.
www.DodgeRam.org has some information about which turbo is which and how to identify them.

The injectors/box means what size injectors or fueling box (24v only) you have on the engine. The amount of fuel being put into the engine can be changed by both, and by other things. You can get many varieties of injectors and boxes for these engines.

For instance, my 99 24v has a TST PM3 box on it. I have a Holley Blue aftermarket fuel pump and 1/2" fuell lines, but stock injectors. I have 13 psi of fuel pressure at an idle. When I am running down the 1/4 I can dump enough fuel into the engine with just that box to pull the fuel pressure to 0 (ZERO) :'(, so I know I need to find myself a better fuel pump, especially if I'm gonna put bigger injectors in it. And my boost only gets to abot 30 psi, with 35 being about the max my turbo can do efficiently.

As far as the efficiency range, known as the efficiency map, I was told those are closely gaurded secrets of the manufacturers. Someone higher on the turbo supply totem pole told me that. I forget what he said about why it is this way though.

Chris

KatDiesel

Since you openly said you don't know much. The diesel world is different from the gasser world. On these engines :

[glow=blue,2,300]Air + Fuel = Power[/glow]

Add only air, and all you get is lower EGT's.
Add only fuel, and all you get is some power and higher EGT's

Add both and whoa away you go.

KatDiesel

Find out there year of the truck and what transmission it has then we can tell you the rated hp and which size turbo. They are all Holset turbos but diffent sizes/models have been on the trucks.

MBC aren't really used much, although they work fine. I don't know of anyone using a EBC.

When he said 70psi he was talking boost pressure, not cylinder pressure. Personally I would keep the boost under 55psi for the stock headgasket.

On the stock fuel system you should be able to net about 25 or so psi, but see my above post.

Rattletrap1

My truck came with upgraded injectors...I'm looking for more boost. I have a MBC on my turbo gasser. Why are these rare on TD's and who has one?

Stamey

[quote author=Rattletrap1 link=board=5;threadid=19670;start=0#msg184952 date=1063655026]
Why are these rare on TD's and who has one?
[/quote]

I think this is because they aren't really necessary until you hit the higher numbers, >500 hp, and not many go that far because they tow or want their engine to last longer. Despite how it might look, not everyone on here is a speed/HP freak. I'd be in the freak group, myself, but I'm just not as fast as the others yet because I haven't saved all the necessary money yet. :P
Also, in many cases, the boost is set up at the right amount by the boost controls of the box, where applicable. When these things get set up they go to the edge of the efficiency map and that's all we can get anyway, so why would we want to turn it back?

Them external wastegates are a pretty penny.

Chris

Lary Ellis (Top)

[quote author=Stamey
Why are these rare on TD's and who has one?
Despite how it might look, not everyone on here is a speed/HP freak. I'd be in the freak group, Chris
Having met Chris, I can back up this statement as fact ;D

Put the gun down Chris, I was just kidding ya 8)

Stamey

[quote author=Lary Ellis (Top) link=board=5;threadid=19670;start=0#msg185025 date=1063666753]
Having met Chris, I can back up this statement as fact ;D

Put the gun down Chris, I was just kidding ya 8)
[/quote]

Don't worry Top, no offense taken. The first step to overcoming an addiction is recognizing you have it. My question is, if I recognize I have it, do I have to overcome it, even if I don't want to? ;D

Chris

Lary Ellis (Top)

[quote author=Stamey
My question is, if I recognize I have it, do I have to overcome it, even if I don't want to? ;D

Chris
Lord I hope not ;D 8)

Rattletrap1

That doesn't really answer my ? On gassers we just put an MBC inline to the wastegate pressure signal. This restricts the pressure from ever reaching the wastegate until the pressure is enuf to open the MBC...hence wastegate remains closed until I reach my desired boost.

I've got injectors, but would like to increase boost without a box.

Is this "boost elbow" available as a standalone and would it do anything as a standalone?

[Why are these rare on TD's and who has one?
I think this is because they aren't really necessary until you hit the higher numbers, >500 hp, and not many go that far because they tow or want their engine to last longer. Despite how it might look, not everyone on here is a speed/HP freak. I'd be in the freak group, myself, but I'm just not as fast as the others yet because I haven't saved all the necessary money yet. :P
Also, in many cases, the boost is set up at the right amount by the boost controls of the box, where applicable. When these things get set up they go to the edge of the efficiency map and that's all we can get anyway, so why would we want to turn it back?

Them external wastegates are a pretty penny.

Chris

Stamey

Rattletrap,
On your there should be a boost elbow just below the intake on the compressor housing. This is the wastegate control line. You can put a valve in the line, or an MBC if you like. When I got my box I also received a modified boost elbow which had a set screw in it to "limit" the amount of pressure that could get through it and make my wastegate open at a higher pressure.
Generally, I haven't seen anyone put an MBC on a stock turbo that has no external wastegate. I don't know what the reason is, but I assume it's because we max them out to the edge of the efficiency map and let'er eat.

Chris

MLR1

Rattletrap,
You need a boost fooler or a box (chip) of some sort, if you don't the map sensor will throw an overboost code with increased pressure. The computer also reduces fuel at 19+lbs of boost. A box will keep the fuel flowing up to full boost.
Hope this helps.

Stamey

[quote author=MLR1 link=board=5;threadid=19670;start=0#msg185475 date=1063737854]
Rattletrap,
You need a boost fooler or a box (chip) of some sort, if you don't the map sensor will throw an overboost code with increased pressure. The computer also reduces fuel at 19+lbs of boost. A box will keep the fuel flowing up to full boost.
Hope this helps.
[/quote]

Ah, good one MLR. I forgot about that as I installed my modified boost elbow at the same time I installed my box.

Chris