I am officially on my own job wise and I am testing the waters. If this is not the correct venue, I sincerely apologize.

After tuning a few 616 NA MW IPs for on and off road use, I am considering building a rig to set up and bench tune MW IPs with RW Governors. This would include changing the Elements to larger ones, changing Governor springs, and individual Governor settings to meet the owners needs.

After looking into this for a while now, I am disappointed but not shocked, by the loose tolerances of the settings that are considered OK per the factory.

Without getting into detail how I would build my rig, all measurement tooling would be certified, Element shims would be custom ground to achieve the finest degree of accuracy of the start of injection between cylinders. Fuel delivery quantity would be measured mechanically, (hydraulic cylinders with dial indicators), as apposed to graduated pipepets.

I would also put on my, (wish), list an engine on a dyno. I have an engine dyno, but it is set up for something else, so I would have to build a new test stand and then get a good engine.

If I were to do this, I would first build up an IP and take it to an independent Injection shop for verification of the settings. If any shortcomings are identified, I would take the necessary steps to address any such issues in order to achieve as close to perfection as possible.

If I survive the beatings that are sure to come, I will figure out potential costs.

As always, your thoughts are encouraged.

I say go for it. I have been thinking about making a test bench myself, but I just don't have the time.

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1998 Mercedes E300TD

1983 Mercedes 240D Turbo, 131bar injectors, Cosworth intercooler and 63' Ford Falcon radiator, Ardic Parking heater, Headlight wipers, Best 38.6mpg.

1973 Saab 96 Rally Car, 1.8l V4 with all the race bits

If you are anticipating that you will be doing this for eventual profit I would be very surprised if there is much of a market. There is infinitely more talk about what people could do, would do, want to do, than there is any realistic willingness of the same people to actually pay for something. Now you might get the occasional young punk intent on throwing away the money mommy and daddy give him as subsidized rent, but I'll bet there are damn few adults who will actually pony up the what, $1000 for a blueprinted tuned IP. With all the work you're talking about I can't imagine that you can do it for much less than that. How you’ll get people to spring that much for something with no track record will be near impossible I’d bet! Maybe if it works and you give away the first ten at cost you might be able to jump start some demand.

You only mention OM 616 and that market can’t be very big to begin with. Don’t get me wrong it would certainly be a worthy endeavor for someone with the time, talent and resources but your rewards are more likely be self satisfaction rather than remuneration I’m afraid.

There are more than a few threads about fantasy projects like transmission adapters, high flow manifolds and similar projects that have 25 guys saying yeah, yeah, yeah, and in the end no more than one or two who actually will write check when the time comes.

do you have any idea how you want to alter the governor setting?
I mean what will be the result of your adjustment (after swapping elements)?
More power clear, but will the governor keep all the functions?
Or even better can you provide a Bosch instruction with your modification for each setting?

Tom

professional injection pump benches cost over $100,000 for pretty good reasons. trying to build one yourself won't make good results.

For the sake of discussion, what would you say if that $100,000.00 machine backed up, (confirmed), my work?

Tom

My experience has been with 5.5mm Element PIs. My 240 has a bad Element and I want to put 8mm Elements to go with the turbo I have for it. That would be my first working with larger elements. I would combined extrude honed nozzles with the larger elements with the goal to reduce injection dwell and increase fuel atomization at the reduced injection dwell, (pulse width).

The targeted goal, regardless of element size, is improved drivability. To me, drivability is made up of qualities that include, smooth and reliable power, predictable reliable performance, good fuel economy, no/low smoke, good lifespan.

"More power clear, but will the governor keep all the functions?"

Yes, the governor(s) are individually adjustable and yet react to each other to some degree. For example, that is why the idle speed changes when the Torque Control is turned up. After not being able to get my engine to return to idle after following the information available on a few different forums, I took a sep back focusing on how a basic Governor works and visualized what each IP Governor does,(Idle, Torque Control, Max speed), and how it does it in correspondence with the other Governors, and figured out how to adjust the Idle and throttle to allow the Idle governor to do its job after adjusting the Torque Control.

The result is, in the case of a 616, that the dash idle control is not needed, even with the A/C on. Improved bottom end / mid range torque and throttle response, with a stronger high end pull.

The total amount of fuel on the top end is about the same in an effort to keep EGTs in a reasonable range due to the poor VE at high RPMs, but by adjusting the TC, I can shift the fueling curve to allow more fuel at lower speeds, (higher VE), and reduce the reduction curve as PRMs increases.

I have seen some Bosch manuals and I am talking with a pump shop in an effort to get some tools and a copy of a manual. After talking with the pump teck I think the best way to go is take a pump that I tuned up off a car and get some base line measurements. Pull the pump down, put it back together, bench tune, and run it. The only spec that I think is needed from Bosch is the start of injection height. The Governor settings are fueling rate related and I could not find any setting ranges other than stock.

My approach would be to put electronic linear motion sensors on the rack and the injection fueling rate/volume cylinders and monitor RPM. This would allow me to graph the, fueling rate and Rack position, curves in relation to each other and RPM. The idea would be to find the desired injector volume at idle, and full power, (an individual engine/driver specific specification), then adjust the individual governors to get the curve that best fits the drivers drivability expectations. A bonus would be to put the PI on the engine dyno and verify the set up.

I totally agree. Tire kickers don't pay the bills. Any investment will have to be able to provide a return in a reasonable time period.

I would be able to work on any MW IP that has a RW Governor. I have done more 616 IPs because they need all they can get. 5 and 6 cylinder IPs would not be an issue as long as they have the RW governor as that is what I am familiar with.

As for the cost for service, $1000.00 is about right. However, as has been pointed out, I would be new without a track record and as such I was thinking, (without actually looking into the actual machine build/run/maintenance costs), that I would be in the range of $500 to $600 for labor, any parts would be added to that. After I have a proven track record I will be able to justify the higher cost.

What would be the difference in physical fit to the OM603 engine? Would it require different hardware, injection lines, etc?

First impression is that it means buying another pump vs tuning a known good one. If it's better though, ... depends on the cost.

__________________

Gone to the dark side

- Jeff

I seem to recall being told that the MW has a shorter control collar length than the M pumps and as such it increases its fuel delivery quantity/mm of rack travel more quickly. This was supposedly one of the reasons for building M pumps rather than MW's as the MW's with big plungers became very touchy when on the engine. I know my M pump has a fair bit more travel on the speed control lever than my MW and that helps to reduce the sensitivity as well. Has anyone verified what the control distances are on the two pumps?

One nice feature of the MW IP is the ALDA rod. Basically speaking, moving it up or down changes the pivot point for the rack lever and thus changes the amount of rack travel for a given throttle lever travel. One could use this feature to control the "Sensitivity" of the throttle.

I still have to look, but I want to order the Delivery Valves that the 8mm Elements use and see what the difference is between them and the 5.5mm Element Delivery Valves. If the collar is different there may be some benefit in drivability.

Another thing I would want is to get some extrude honed nozzles. I am thinking around 25% larger area. Reason behind my thinking is given a set quantity of fuel and injection time, with a larger nozzle circumference, the amount the pintel would have to move would be less than with a smaller circumference.

As a result of the reduced pintle lift, the gap between the pintle and the nozzle orifice that the fuel passes through would be tighter which would aid in atomization.

A smaller orifice would require that the pintel lifts higher, making the gap wider resulting in a thicker fuel stream so to speak.

In addition, if you reduce the length of injection time and increase the amount of fuel, I could see a small orifice pintel over traveling from a pressure serge. A larger orifice would be better at releasing the pressure while keeping as tight of a gap as possible.

All and all, IMO one can not change one thing in a balanced system and expect it to still perform as a balanced system.

If one changes one aspect of a balanced system, the other aspects must also be changed to compensate for the first change.

Does anyone know for certain, the size of the elements in the 603.970 pump (3.5L)?

__________________

Gone to the dark side

- Jeff

5.5mm!

The type plate PES 6 M 55 ...
tells the plunger diameter.

Tom

Thanks Tom.

__________________

Gone to the dark side

- Jeff

Only the 606a got larger elements. only 6mm though, not really worth the effort with 7 and 7.5mm available for the same cost.