I'm in process of swapping the MW-pump to a M-pump in my W460 G-Wagen. Plan is not to get a rubber burning beast but a modest daily driver, so max 150hp. Fuel economy is also important.. if you can mention G-class and fuel economy in a same sentence.

I could get 6mm elements from 606 pump for free, or pay about $35/piece for the 7mm elements.

Is there any advantages to 7mm elements if I'm not after big power? What I've understood, with 7mm elements I could get more low end torque and better fuel economy..? Is there any downsides?

More power does not normally equal better mileage. The stock calibration is designed to reduce emissions and give reasonable performance. After that there is little bit of lea way that you can use to get better performance but that may not get better mileage.

It is also going to depend on your expectations and where you spend most of your time driving. If you spend most of the time on a Freeway or City driving.

Personally changing the elements is gong to be expensive an you are not going to achiever what you want. It is more for those for who power is the number 1 concern at the expense of the rest.

Assuming you changed the parts yourself and you knew how to phase/time the Elements properly changing the Elements would still mean sending your Fuel Injection Pump to shop where they would run it on a test stand and calibrate it. Then if you wanted more then stock fuel injected you would have to tell they what you wanted the pump calibrated to.

The ADLA on the fuel injection pump limits the amount of fuel when there is no turbocharger boost. Removing (or without removing you could simply see if the provided adjustment gives you some more pep) that removes the limitation but won't give better mileage but could give a pepper lower end.

On the MW fuel injection pumps there is a rack limiter that people re-adjust to get more fuel

I don't know about the emissions stuff like the EGR and any sort of Trap Oxidizer making a performance difference.

Turbocharger waste gate adjustment so that you get the Max boost from it.

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84 300D, 82 Volvo 244Gl Diesel

I assume you are talking about a 617?

I have a few takes on this...kind of all over the place but here goes.

IF you only want 150 hp, I believe some have achieved close to this (like 145) with maxing out the stock pump and swapping a newer turbo, exhaust and intercooler in.

Since you have a G, you probably are more focused on low end, so this set up may serve you best. A newer, faster but not necessarily bigger turbo will give you some more power by spooling sooner without sacrificing mpg too much. For example, a Holset He221 is small but flows a lot of air on both ends and since it is a newer design should spool sooner as well.

Now, as a 6mm owner in my 603, I wish I had gone to 7. I am limited to about 90cc of fuel, which in theory could make 260 hp. No idea what I have but I estimate maybe 240. My end goal is around 300 now though so being able to turn it up to 110cc would have been nice. Instead I will need a new pump. Overall though, I am satisfied with my current performance so I may stay with what I have.

If you are going to go through the expense of building a pump it would be best to get the bigger elements and have it set for low power. If you get 6mm elements out of a pump for dirt cheap then maybe that would work too. The 6mm would definitely be good for more that 150hp with mods.

I have had no decrease in mpg. In fact my best to date (which was 31 on a full tank) was with new pump and exhaust, manifold, turbo, etc. Whether that can be attributed to any one of these in particular is up in the air. I still got 29.5 with the pump and stock exhaust and stock manifold though.

Lastly, I drive the car as I would normally without mods so if I was constantly flooring it, etc I would expect much worse mpg. But, it's nice to be able to open it up here and there when needed

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Dan
2005 E320 CDI - 246k
1987 300SDL TD05-16g, Herlevi pump, Elbe manifold, 2.47 LSD - 213k
Past: 1987 300D - 264k

I love those older style G-Wagons. Isn't yours a naturally aspirated engine? I don't recall seeing that they put turbos on your generation of chassis.

I've seen some people out there swap in turbo 617s. There are special elements within the engine that the NA lacks such as piston oil coolers. If you're going to upgrade your pump, I would go the full monty and get a rebuilt om617 with a turbo on it. No sense upgrading the IP of a naturally aspirated engine without giving it more air.

Probably not the suggestion you'll want to hear, but the later style OM 606.964 engine from the 1996+ G-Wagons gets around 20 mpg which I believe is astounding given the brick like qualities of your truck.

Since you'll probably be pulling the engine anyway, it might be worth investigating such a swap. You can definitely find e300d turbo'd engines of the same vintage which would have all of the goodies you'll need for such a swap.

Food for thought, good luck on your mods

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-Typos courtesy of my mobile phone.

Yes indeed, it is 617. I wrote a longer post about my pump adjusting problems but I thought it disappeared.. but it's now just below this topic on the forum. Anyway to cut it short, when the engine was swapped (N/A to turbo), I also changed the original turbo to 603 turbo and put in an intercooler. I've tried adjusting the pump but I'm not even getting the power the engine should have as stock. That's why pump swap.

Originally it was NA, now it has the 617 turbo.

Being early 80s, my truck has older style engine mounts and putting in anything else than 617 would be laborous.

I just bought a 99 e300. Dieselmeken timed a 99 e300 to 10° atdc and installed a modified injection pump. Is it possible to get a performance improvement by going from factory timing of 15° atdc to 12° atdc.
I did the exact modification on my 85 300sd and it made a noticeable improvement. But I haven't seen anything, other than a video from Dieselmeken, that deviates from the factory setting.
Roddy

Sent from my SM-G900I using Tapatalk

if you already have the M pump to swap in along with the injection lines and linkages i would recommend getting the 7.5mm dieselmeken elements. the 6mm should do 150 easily however the 7.5 should slightly help your off boost power since they shorten the injection duration time along with potentially a tiny bit more mileage. as for the turbo the 603 turbo is not too bad and will do 150hp but it will be near its limit there and is not as efficient as more modern turbos. i have been running an 8mm pump with a holset HE221W and it is quite streetable full boost by 2250 rpm with over 10 psi by 1500.

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1985 300D om617: 8mm M pump 175cc 5200rpm, holset he221w @ 30psi, large A2W ic, compounds on the way.
KD9AFT
A&P

Timing. That was the question. I did see where the turbo pump was modified with 7.5. And was timed to 10 atdc. The engine sounded really crisp. With absolutely no hesitation. I noticed the same thing when I advanced my 617. But haven't heard whether the 606 can be advanced using the stock injection pump. I tend to think the 606 should react similarly to a 617. But I'd like to know if someone else has advanced their timing and what the results were before I advance my pump. That sounds reasonable. Right?

Sent from my SM-G900I using Tapatalk

Not sure on whether you can do this advancement on a stock pump but when the pump builders make pumps with bigger elements they generally have very different timing requirements due to what they did in the pump. For example, my 6mm pump is set for 15 BTDC. But if you are just going to advance your stock pump a few degrees it should do the same as your 617 i imagine.

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Dan
2005 E320 CDI - 246k
1987 300SDL TD05-16g, Herlevi pump, Elbe manifold, 2.47 LSD - 213k
Past: 1987 300D - 264k

7mm elements. You will have a shorter injection duration, and the overhead for more power in the future.

If you want good mileage, adjust the nut behind the wheel.

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