Not without modification.

No, you asked for about increasing the volume of the injectors.

You can increase the volume of the the injectors simply by pushing more fuel through. Of course this makes for a longer injection time. The only way to get more fuel out of these pumps is larger elements. To this end there is not a whole lot of options. 8mm elements are super rare and 10mm elements are common but are to large and both of these have a different stroke. Nobody has really found out if the stroke is compensated for at the cam or if it's just the nature of the beast. 10mm would probably be WAY to large.

Mike,

There's been talk of EDM or Extrude honing the nozzles for better flow but I'm not aware of anyone actually doing it. Unlike with the trucks, it seems that the Mercedes guru's don't work with the injectors all that much. Rather, they devote most of their energy to optimizing the pumps.

There's a couple turbos that come stock on these, none worth a hoot. An excellent mod that's been done by several guys here is to fit a VGT from a Sprinter or a Liberty to gain a little more boost and much faster spool times.

The same rules apply for turbos on these engines as the 5.9. You still have to ultimately move the same amount of air through the engine to generate the same HP. A turbo that supports 300HP on the 5.9 will probably work well on these 3.0 motors. HX or HY35 maybe? If you make a split manifold and have half of the exhaust dump into each side of the split scroll turbo, the lag won't be so bad.

The timing is adjusted by rotating the pump. I see people use the "drip tube" method or some use a "sonic" or some other electronic timing pickup to measure.

That makes sense. So everyone that raises their pop pressure really needs to change the Delivery Valves and springs as well.

I was typing as I was thinking instead of thinking about what I was typing. I was thinking if the concern was regarding the velocity of the fuel traveling through the helix at the end of injection, that if the capacity of the helix and barrel port was increased to allow for a higher volume of fuel flow that the velocity of the fuel traveling through the helix at the end of injection might be lower. No intentions here, I was just thinking.


So it seems there are two events (start of injection and end of injection) that can cause erosion of the element speed is too fast at the time of the event. A larger element would create a faster pressure rise at a slower speed would it not? If so then the bigger the better?


I figured on using the 8mm elements and modifying the helix to reduce the volume per degrees of element rotation in an effort to reduce rack position sensitivity (improve speed control), as well as to adapt for the shorter stroke and now cam profile.

Be sure to keep us informed as to how your new elements work out.

om616: sourcing the 8mm elements is all but impossible and they are the wrong stroke. Same stroke as the 10mm. Unless you know something I don't know :D

I was watching YOUR thread in the SuperTurbo sight that found some from China. As Tomnik stated, the effort died at the point of ordering. Do you know something I don't?:D:D


My thoughts on this are that the 10mm elements are for larger engines and I will be using less than 1/2 of the output capacity even with the shorter stroke. Anyone feel free to do the math to get a better estimate for 300HP with a 617.95.

It is dangerous to do so, and Tomnik may want to comment here, but I am "assuming" that instead of increasing the height of the cam lobe, they lowered the base circle to get the additional lift. If that is the case the installed barrel height can be corrected with shims.

After start of injection, my new understanding is, that as long as the injection ends before the fastest (lift rate) portion of the cam is reached, all is good. The remaining stroke is used to decelerate the element.

I would imagine that the 8mm element helix is set to move more fuel over a longer effective stroke for a larger engine, (although the actual effective stroke of the 10mm lift cam may be the same as ours, with the extra cam lift being used to aid in the deceleration of the extra mass of the 8mm and 10mm elements), and since I will only be using a fraction of the capacity available with the 8mm element, I would modify the helix to reduce the output capability (taking the effective stroke into consideration) and spread the capacity (increase the span of the volume) over the useable range of the governor. It is my understanding that the goal is more fuel with an equal or less stroke.

Worse case scenario I have to deck the pump to drop the barrels. Ideally, if Tomnik's elements work out that would be the way to go since he has already done the engineering. Until someone tries to make them work this is just an exercise in theory. I will not be ready for this stage until next summer at the rate I am going.

Anyone using a lift pump?

http://www.detali.ru/cat/oem_mb2.asp?TP=1&F=210020&M=606%2E912&GA=722%2E438722%2E600&GM=717%2E446&CT=F&cat=45P&SID=46&SGR=075 &SGN=03

See part #250 for my electronic IP. Part has changed very little for +30 yrs. Approx 50% of the fuel it feeds the IP is dumped back into the tank via the return line.

Perhaps you meant to post this picture... :)

http://www.detali.ru/cat/cats/my.mycat?Pic&syspm=537a4e0c04020c6238282e2775161d81b78ad0d0d6cfdaedf3f9f6b1faf9bdf3c6948c9283929be1d 3e9dff2a8b2b14548093f11271a407768297f52454f4c4177&pm=0b32065b4e4143481e736e6861727a7e3d01777c7f67626 b6f53575f575d47484fb7b5bf8da396c4dcece2ede9b187958afbf2f2fcebd5ebdebcb3a4eda39e98af62757f7c1127

I thought I did do that Evan. Thanks.

Don't know why the right link didn't copy. Looks a lot like the lift pump on my 85 minus the manual primer pump.