cwh
cwh SuperDork
12/30/11 9:52 a.m.

We have all seen the insane 1000hp trucks belching smoke while running 10 second ETs. Can any of these hop up methods be applied to the MB diesel cars? I'm sure the fuel injection system will be a problem, but can it work? Could be a lot of fun.

BoxheadTim
BoxheadTim GRM+ Memberand SuperDork
12/30/11 9:53 a.m.

Depends on the model I believe.I also don't know how much hop up parts are available, but there's someone in Scandinavia who built a W123 station wagon drift car using a much bigger turbo and IIRC a later engine.

pinchvalve
pinchvalve GRM+ Memberand SuperDork
12/30/11 9:59 a.m.

Sure, swap in a Cummins.

jstand
jstand New Reader
12/30/11 10:11 a.m.

I haven't dealt with any MB diesels but they should respond to the same changes as other engines:

More air (boost) More fuel = More power

You can probably have the injection pump turned up to increase fuel volume/ pressure, injectors set to higher pop-off pressure, and possibly governor RPM changed.

As suggested more boost, free flowing exhaust and intake.

You can also get extreme and add propane injection, and/or water injection if running high boost without a charge air cooler.

Anti-stance
Anti-stance New Reader
12/30/11 10:35 a.m.

Its all in the injection pump and injectors. There was a guy out there that used to hop up MB pumps with putting bigger plungers and yadda yadda but it was pretty pricey. I can't remember the name of the guy.

Same goes for VW diesel performance, all about the pump and injectors.

dyintorace
dyintorace GRM+ Memberand SuperDork
12/30/11 11:24 a.m.

According to this video, the answer is yes.

http://www.youtube.com/watch?v=-gVUwDJ1QyY

carzan
carzan HalfDork
12/30/11 11:33 a.m.

The Finnish seem to be the "go to" guys for Mercedes diesel tuning.

Diesel Tuners

Hope this helps.

EDIT: Sorry, I should check links in forums before posting, but a google of key words like "Finnish" "Mercedes" "Tuners" "Mods" should get you started.

93EXCivic
93EXCivic SuperDork
12/30/11 11:41 a.m.

I know on the OM617 the big limit is the injection pump. Basically the limit with the stock pump is about 180hp. After that point you are looking at around $2k to get the pump rebuilt with a bigger element.

DoctorBlade
DoctorBlade Dork
12/30/11 11:55 a.m.
a401cj
a401cj GRM+ Memberand Reader
12/30/11 12:06 p.m.

abso-berkeleying-lutely they can be built up. I think the biggest hurdle though is that there isn't much in the way of an aftermarket like you have for the Cummins, Powerstroke, and DMax guys.

93gsxturbo
93gsxturbo HalfDork
12/30/11 4:21 p.m.

Cranking up a diesel hinges on a few things.

How much fuel can the fuel system deliver? Some engines like the 94-98 12 valve Cummins used in a Dodge Ram come from the factory with their fuel systems detuned a long way from their possible output, while other engines like the 6.5 turbo diesel used in GM trucks of the same era are pretty much running at maximum output on the factory floor. Issues that control how much fuel is delivered is what sort of pump or injectors the vehicle has and where they are in terms of duty cycle in stock configuration.

Another limiting factor is just how strong the engine and driveline is. You can't turn a 6.5 turbo diesel up too far because of the strength of the engine. It just isn't designed to run at 500+ horsepower. It will run forever at stock output, but there isnt a very high ceiling for power. A 12 valve, P pumped Cummins can easily become a 500 horsepower, 1300 ft/lbs motor without even opening it up, but you will spend big bucks building a transmission that can live behind a monster like that.

Knurled
Knurled GRM+ Memberand Dork
12/30/11 4:33 p.m.

Turbodiesels, IMO, are to be looked upon with a kind of fascinated horror. The part that always gets me is, if you want to keep the engine from blowing up, you turn up the boost and cram MORE air in, since more air makes it run cooler.

Gale Banks has a lot to say about Diesels that smoke, too.

93gsxturbo
93gsxturbo HalfDork
12/30/11 6:08 p.m.

Unfortunately, more boost doesnt mean more power. There is usually little tying fueling to boost levels at wide open throttle. There is typically some sort of aneroid boost reference for part throttle and no boost/boost transitions but all that does is make sure part throttle fuel matches part throttle boost to reduce smoke.

And then you run up against the wall I pointed out earlier about making sure there is enough headroom in the fuel system and you have the means to get to it to use the additional boost. Some engines are really close to maxed out in stock form and getting additional headroom in the fuel system costs real bucks and affects drivability. Other systems have a ton of headroom in them, and simple fuel mods pay off big dividends.

Simply adding more air to a properly running diesel doesn't do much. It may lower EGTs a bit as long as you are within the confines of the turbo and charged air cooling system to dump the extra heat generated by adding boost, but if the engine already runs well you will only see a negligible performance gain from upping boost alone.

Diesel modification 101. Add as much fuel as you can before running out of pump, injector, or strength in the engine, add as much boost as you need to burn that fuel, and rock and roll.

corytate
corytate HalfDork
12/30/11 6:52 p.m.
dyintorace wrote: According to this video, the answer is yes. http://www.youtube.com/watch?v=-gVUwDJ1QyY

damnit. that video made me do a quick craigslist check for mercedes trubodiesels and vw tdi/ and there are some here that I would love.
damnit.

curtis73
curtis73 GRM+ Memberand SuperDork
12/30/11 10:34 p.m.

In general yes. You'll be limited by a few things like rod strength and turbo flow. The truck diesels are often designed as medium duty engines with modest tunes so there is a lot of potential for "turning them up" but MB diesels are pretty well matched as-is.

Diesel tuning is based on peak air mass versus peak fuel delivery. Depending on how boost is controlled (some diesels have no boost control) you can often times up the fuel which in turn sends more mass through the turbo and consequently more air. Depending on the hardware, you might be able to double the fuel before you run out of air (or hit surge) or you might only be able to add 5% more fuel.

Here is the general recipe for most hotrod diesels. First, always do the basics. Cool air intake, massive exhaust, and EGT gauge. The intake and exhaust will lower EGTs and often times give you a pretty impressive jump in power, but those first three mods are key before you start messing with fuel delivery. Not only is it a bit pointless to add more fuel before ensuring adequate airflow, but monitoring EGTs is an absolute necessity to prevent expensive damage.

Then, play with fuel. Tuners with experience can point you in the right direction, but often times the first step is advancing the injection timing. This will add a bit of roughness and noise (and also spike NOx emissions big time) but it will increase power and efficiency a great deal. Basically you are limited by time. Diesel burns slowly, so excess fuel (or fuel that is injected late) makes more black smoke. Advancing the timing not only makes more peak cylinder pressure immediately after TDC, but it also gives you more time to burn the fuel you inject. More time = more fuel you can give it = more power.

MB stuff is tricky, finicky, and expensive. I suggest getting a pre-computer, mechanical injection model. I had a 99 E300 and was planning to swap to the older 6-cylinder mechanical stuff before modding but never got around to it.

You'll need to log in to post.

Our Preferred Partners
sNpFPJ5Uenj3kxL7L71sYSNnOLYxMf1Emb0RqFt1RLcuLKxRuDE4cgWDp1OiHNgm