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1984 300TD
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Discussion Starter #1
Hello turbo boost sharp shooters
I'm trying to get my 1984 300TD 617.952 with 4 spd manual trans swapped into it first to operate normally then to crank the boost up
Its a complex system so I'm still figuring out "normal function", making sure temp sensors, EGR, injection nozzzles and pop pressure, pressure converter, control rod travel, are operating normal.

Swapping out the automatic trans for manual may complicate this so if anyone can comment, honestly I do not recall which vacuum or electrical circuits were abandoned in that process.

So far boost pressure is a puzzle, which hovers at zero until around 2000 rpm then with flooring the accelerator it jumps right up to 9psi as RPM approaches 3500 but does not go above that. In other words the plot attached is shifted to the right but is otherwise approxamately correct.

It anyone can suggest where to sleuth out why its not corresponding to the plot attached from FSM
thanks in advance
Rocket
 

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E320/E250 Bluetec Ford F350 6.7l
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Some owners put bigger spring on waste gate to increase top boost, but you have pretty aged car, so before you go that far, make sure everything is in perfect order.
Turbo lag was normal thing for the era.
 

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1984 300TD
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Discussion Starter #3
Thank you sir.
This engine is less than 100K miles post rebuild, has good compression so should be fun to up the boost.
However the peripherals are or could be old and I must finish verifying they are operating correctly.

I gather since its Garrett then the simplest boost increase will be one of the gizmos the restrict pressure reaching the wastegate. Correct?

Tearing whats left of my hair out nobody on these boards see to mention who makes those kits.
 

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E320/E250 Bluetec Ford F350 6.7l
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Don't expect aftermarket still working on parts for 35 years old technology.
I know those cars are still daily drivers in California, but not too many of them anywhere else.
Modulating the vacuum require some high-tech module, when adding a spring is rather simple.
 

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1984 300D
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The Waste Gate spring tension is adjustable.
However, you can put a turbo boost controller inline with the waste gate hose to control when the waste gate opens there is cheap ones and more expensive ones.
2000 rpms is when the boost normally takes effect. More then 12 psi of boost won’t do more for you without doing other stuff.
The ALDA cap can be removed to make an adjustment to give you more fuel with less boost but you should read up on that first. More fuel equals less fuel economy.
Some had a KKK Turbo and it is claimed it does better on the low end speeds.
 

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1984 300TD
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Discussion Starter #6
Thanks for your comments. This is Garrett so not so easy to get adjust the stock waste gate.

By end of day today I should have this setup installed. http://www.geocities.ws/chmwatson/FAQs/mbc.html.

The FSM file page does show a plot of boost ramping up at lower RPMs and it maxes out at .7 to .8 bar which some enthusiasts on some boards state they get that I'll look for that with the home depot boost controller

Some say you can take it to 15psi safely.

I'll look for the ALDA capsule mod you refer to. ALDA adjust should do fuel increase or decrease to some degree it would seem.
 

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1984 300TD
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Discussion Starter #7
Silly me .... you refer to small central cap over the central adjust screw with the 10mm hex locking bolt. Gotcha.
 

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9psi is what every car was set to from the factory. More than 12psi will not increase power. For more you will need to adjust the governor internally of the injection pump. Adjusting or removing the ALDA will not increase maximum power.
Beware turning up power, the stock clutch can NOT hold more torque and will slip.
 

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1984 300TD
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Discussion Starter #9
why is FSM saying 10.5 to 11.5 psi???
and showing a ramp up of boost from idle on a strait line to +- 4000 rpm
my 617 is mostly zero PSI until 2000 rpm more or less
can you account for this descrepancy?
It was hitting 9 then dropping like a rock
It never got to 4000 rpm at all until installing a boost controller
period
 

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9psi is just how they were set on the assembly line. There is no explanation other than that. In 18 years of working on these cars I have never seen a stock OM617a make anything other than 9psi, Garrett or KKK turbo.

You have a fuel issue. Check that your throttle lever touches the stop bolt when the accelerator is pressed to the floor, replace your primary and secondary filters, if the primer pump leaks fuel when you pump it then replace the primer, check your air filter, clean the banjo bolt on the back of the intake manifold, adjust the valves if it has not been done in the last 10k miles, make sure the EGR valve is disabled and make sure your shutoff actuator is not recieving vacuum from a leaking key switch valve.
 

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Discussion Starter #11
Now that a boost controller is installed evidence suggests waste gate was "over wasting". Boost shot up much higher, with good power increase from that alone. I will need to be careful it was such a sudden increase.
 

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Discussion Starter #13 (Edited)
It shot up at moments my foot is all the way in it. All the way. During normal driving that never happens. The only time I have ever put my foot all the way in it has been to test the result of adding the boost controller.

I'm interested in boost that makes normal daily driving more spunky. Major bummer, its still flat (+ or -) until approaching 2000 rpm and I put my foot in it.

FSM shows a plot where boost increases along a strait line from 2.3psi at 1000 rpm to 10 at 2000 rpm. Mine is still at zero at 2000 rpm until I put my foot in it then it reaches 10 psi at 3000 to 3500. It is probable that plot is in pedal to the metal condition. Still its not perfoming up to spec.

This is the problem. Why this discrepancy? The boost will get up to 10 or 12 but not until rpm is way above any engine speed occuring during normal driving. Could the turbo need rebuild?
 

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1984 300TD
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Discussion Starter #14
Can anyone explain why the OM617 FSM shows boost ramping up starting 1000 rpm then hitting the max .7 to .8 bar at 2000 rpm, in my case its flat zero at 1000, starts ramp up just under 2000 and hits max closer to 3500 rpm
 

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With a manual, you have a vehicle configuration that never existed from the factory so that graph no longer applies. The torque converter in the auto is a major factor in it, the engine would never be operating at 1000rpm loaded because torque converter stall speed will always put the engine 1600-1900rpm the instant you give more than a little throttle in gear.
 
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