Soo, I've been a long time lurker..
My granny bought a 78 300D new and my mom recently got it and then neglected it, that is where I came in.
I bought an 83 300sd last September and have generally loved daily driving it and fixing all the little broken things.
I filled it up with bio first tank and never looked back, but there was one tank when it wasn't tactically feasible and I had to fill up with petrodiesel, and it was shortly after I had adjusted the Alda out a half turn. It woke up the car out of the hole. I distinctly remember rolling a bit of coal driving thru the neighborhood where my job site was all that week before the boost came on.
But in the months that followed no smoke even off lights full throttle(biodiesel was the primary fuel)

I was going to sell the sd as I recently got granny's old non turbo 300d from my mom and don't need three diesels(have a dually as well). I intended to 4speed swap it, but now I want to use all those manual trans parts on the 78. My buddy recently got the a/c functioning on the car and it is for sale at ~$2000 on atlanta Craigslist.

I want the 300d to not be such a slug, with the a/c on once shifted to second(I don't count super-low) at 25-30mph, there is no accel if there is any degree of incline.
Point of the story is that I snatched a k26 and manifolds and downpipe off an 84 model from pullapart the other day and intend to install it although I have the York compressor(tight fit for an air filter? Or is it even feasible without later model turbo a/c lines and compressor placement) So I have been adjusting the Ada up in half turn increments and am now at 2.5 turns out. Only a half turn was distinctly noticeable with my 300sd Alda, but the 78 only maybe is slighty quicker in final gear. No smoke at all.

I distinctly remember back in the late nineties as a young buck being enthralled by the smoke the 78 would lay in the rear view when I would floor it on the interstate, and it was consistent, not just a getting the carbon cleaned out one time ride.

Before I install the turbo, I wanted to roll a bit of smoke so that the car would be quicker and set it at 6psi, love life, do a 3.07 instead of the 3.42 and ultimately install the 4speed swap and maybe a manual steering box. I can't get any smoke, how far can I unscrew the Ada? Will it take some internal modifications (tinkering) of the pump, or should I pop on the spare 82 300sd turbo injection pump I have laying on the shelf. I also have some high mile turbo injectors, would it be worth installing them over my monark n/a injectors?

I have only 5 gallons of bio in it( just pulled the tank screen-clean) so I am thinking of filling up with stinky petro tommorow to see if I can get smoke. Or would that not be worthwhile(petro is more expensive than bio and obviously will make your eyes water whatnot)

So, does bio not smoke even when over fueled or am I crazy. Also if anyone who has turboed an n/a 300d could tell me about the York compressor fitment issue. Sorry it is such a saga

Huh, what....omg....

Please please please before you start going all Frankenstein on this car do some research....

You cannot install a turbo on a non turbo.....
You cannot install a turbo IP...
You cannot install turbo injectors...

Well technical you can, but at the cost of killing the engine....

Lastly, an ada is not an alda....you are not suppose to mess with that screw for fear of destroying the IP...

Why don't you, instead of pondering ways to Frankenstein the car, do some much needed maintenance. To increase horsepower....these cars are 77hp.....there is no way to increase horses besides installing a type m pump....early non turbo 300d's differ from 80s non turbo...

Do a valve adjustment!!!
Replace filters and primer pump
Do another valve adjustment
Change the oil
Replace injectors
Do another valve adjustment.
Service transmission.
Service rear end..

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The Ada from what I understand is an altitude fuel adjustment that limits or allows rack travel. I have done quite a bit of research, reading voraciously for hours on end here and std going on a year now.

I have done valve adjustments, serviced the diff, trans, and changed the engine oil. I am on my 2nd of both fuel filters since switching to bio and my fuel tank screen is clean. I am not saying the car is slow for what it is, just that it is a creeper compared to my heavier 300sd (and somewhat annoying for other drivers on the road when the a/c is on)

I've stretched my fuel pressure relief spring and done monark injector nozzles. The car is markedly quicker than whe I began, but no smoke...
I will install a turbo on it and back out the fuel load screw a turn. I was just looking for some insight, not that you CAN'T do this or that. I understand there are differences in that I lack piston oil squirt ers and sodium filled exh valves, among others.

If I melt a piston then i will simply pick up a turbo motor and likely do the manual trans swap at the same time(as the auto trans shifts perfectly) in the meantime I will use what I have now.
Thanks for helping me clarify my position

why not just buy a turbo motor instead? I mean why ruin a perfectly good engine? every day that passes there are less and less of these old diesels on the road so why destroy another?

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1978 300D

Less or none smoking with BioDiesel is tipical. Everything that you've done to the engine would serve to increse fuel burn eficientcy thus reducing smoke. If smoke is what you're looking for then i think youre going in the opposite direction from acceleration or top speed improvements.

If you wanna turbo the NA I'd say go for it! I've often thought that a slight and controllable boost would be cool to have. To be able to kick it in on demand and then turn it off to save the melt. IMO

Phil

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Current fleet
2006 E320 CDI
1992 300D - 5speed manual swapped

former members
1984 300D "Blues Mobile"

1978 300CD "El Toro"

When you ask for advice on doing something crazy that has every probability of killing your engine, don't get mad when people who are experts tell you it's a bad idea. There's a HUGE difference between reading things and forming theories, and having years and years of hands on experience and knowing how things will come out. It's your engine. Do whatever you want with it and good luck to ya for that. But come on...have a thicker skin! Don't get all snitty and offended when someone is trying to help you.

Ok, I am not trying to come across as pissy at all. I am not really green (fabricated some race cars and built a few motors whatmlt) nor am I attemptimg to burn a hole in my pistons. I will install a boost and pyrometer gauge and can almost promise you all that I wont melt her down!

I am just looking to bounce ideas around, and I can assure you as long as I am alive this car wont get sold or crushed(32years of age). I am at this point considerimg remote mounting the turbo in the front pass corner of the engine bay as I value my working a/c system and dont have 500 to spend on a sanden conversion and compressor.

That would facilitate the front mount intercooler thT I already have( initially intended for my 2jz na-t cressida project) I am just too hot on these deisels and seem to have lost my oassion for my race cars...

Thanks to all who chip in no matter the opinion.

Neither of my OM616's smoke much at all under any condition - just the faintest blue haze when cold or under heavy load. Seems like black smoke = wasted $$ in the form of unburned fuel. N/A 5-cyl engines are getting harder to find. I will add my voice to the mix as one saying if you want a faster w123, sell the '78 N/A to someone who doesn't want to play 007 on I-85 and use the money ("grandma's car" increases your sale price ) to buy a later model in good condition with a turbo engine factory installed.

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Current Mercedes
1979 maple yellow 240D 4-speed

Gone and fondly remembered:
1980 orient red 240D 4-speed

Gone and NOT fondly remembered:
1982 Chna Blue 300TD

Other car in the stable:
2013 VW Jetta Sportwagen TDI / 6-speed MT

Yes, I understand that on a naturally aspirated engine smoke is a waste of fuel, gross polluting and a potential for meltdown. But my theory is: get it a bit rich then add boost to eveven out the air/fuel ratio and Bam! Use less pedal to achieve the same or more acceleration. Lets be real though, once it is faster, I will still be matting it everywhere trying to catch/beat the gassers just like I do in my 300sd

Biodiesel does not Smoke as easily as normal Diesel Fuel but on the other hand it takes more Biodiesel to get the same power level.

So when your Fuel is maxed out with Biodiesel cannot create as much power as regular Diesel Fuel because drop for drop Biodiesel does not have as much potential energy to tap in to.

Find a site with a Copy of the Factor Service Manual and adjust your Throttle Linkages and of course replace any of the Linkage parts that are worn out.

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84 300D, 82 Volvo 244Gl Diesel

This is really turning into what I want thread not a is it feasible thread.....kinda sad....seems like no matter what is said, this car is going to be molested.....

I think the best thing to do is sell this car and buy a turbo. When you figure out the build year is probably a 1977....this car reaches collector value....meaning first year of production....depending on the condition, you can probably get 10k for it....with all the work recently done it....

Like was said, the na engines are hard to find and it seems a shame to kill one....

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There are many examples of folks adding a turbo to the 240D 4-cyl motor without emploding the engine. If you do set the boost at a modest 6psi limit I'd be surprised if that caused problems, especially if you add the pyro and kept your eyes on the temps.

turbo'ed 617's are fairly cheap and available so you might find that you spend less time and $ to swap a complete turbo'ed motor instead of adding a turbo to the existing n/a motor?

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You can't always get what you want, but if you try sometime you just might find you get what you need.

Long ago, I remember M-B diesels typically smoking and having black soot all over the rear end, but that must have been 70's cars, or maybe fuel quality improved. My 84 & 85 show almost no soot on the rear and the 84 is even a white car. The turbo pistons are much different and the engine block is different, with oil jets that spray upwards on the piston to help keep it cool. Since your engine has little value, I agree with you trying to turbo it first and be ready to swap in a real turbo engine if it fails. What's to lose and maybe it won't fail for 150K miles. Only if some people chime in "tried that, and my engine failed in ___ miles", anything else is just speculation.

I lucked out at bought a 300D turbo engine off craigslist for $300, including the starter, without even running it first. It runs great and starts immediately, and shows no blow-by from the PCV opening at all. The cam even looks new from what I can see thru the oil fill hole. There are a lot of 300D & 300SD's winding up in the junkyards now, so you might find a good engine easily.

Hmmm, that is one thing I have yet to do: sit someome else in the driver seat and seen whether I am even getting full linkage travel... Good call

I am never selling the car because it was my grannys and im the family since new, plus that was a stipulation of the sale from my ma.

^^^^^ That seems like even more of an incentive to keep the car original. It is probably useless to mention, but non turbo engines can also rack up more milage then a turbo....

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