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Cruise Control
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Discussion Starter #1
I'll be posting in this thread about my upcoming engine swap, in which I'll modify a recently acquired '99 OM606 Turbo and install it in my '87 300TD.

I've been steadily upgrading the chassis for this swap, including an intercooler, a Sportline suspension rebuild, Limo/500E swaybars and SL600 brakes. Now I'm ready to take it to the next level, that I'm targeting to run in the 300hp to 350hp range.

Current engine:
OM603 (3.0L 12v) with a stock rating of 148hp [theoretical maximum modified output ~450hp]

I've tweaked the pump so that output is now somewhere in the 170hp-180hp range. When I flip the propane switch, it may run anywhere near 200hp. This is the original engine with 232k miles. Runs great and uses very little oil...drips well, that's another story.

Donor engine:
OM606 (3.0L 24v) with a stock rating of 175hp [theoretical maximum modified output 500+hp]

This engine was originally designed to be a drive-by-wire setup, so I'll be installing a mechanical injection pump from an OM603. I'll temporarily be using a slightly tweaked stock pump with 5.5mm elements, but will be sending off the unit that's currently in my wagon to Finland, where they'll install 7mm elements. The real limitation to power output is the tiny little KKK turbo that's currently on there. This won't suffice once the modified pump is fitted, so I'll need to investigate a more suitably sized model before the pump is sent back. The engine has just 78k miles on it, and it's dry as a bone.

Modification unknowns:
Oil pan
Oil filter housing
Cruise actuator
Throttle arrangement
Engine mounts
Flex plate
Temp sensor locations
Serpentine belt issues
Wiring (minor)

btw: This has been done before, but I may be the first in NA to make the swap into a 124
 

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Cruise Control
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Discussion Starter #5
Modification unknowns:
Oil pan Needs the 603 version swapped over, 'cause the 606 is a different shape. Will also need the oil pump swapped
Oil filter housing Needs the 603 version swapped over, 'cause the oil cooler lines interfere with the cruise actuator
Cruise actuator Needs to be slightly modified 'cause the upper lefthand mount interferes with head
Throttle arrangement still unknown
Engine mounts Needs the 603 versions swapped over
Flex plate Needs the 603 version swapped over
Temp sensor locations I'm just using the 603 coolant temp and Aux. fan sensors
Serpentine belt issues Needs the 603 H2O pump pulley swapped over, 'cause the 606 version is smaller
Wiring (minor) This is an opportunity to clean up the stock wiring and eliminate the un-needed EGR management stuff
Minor update:

I'm most of the way through dismantling the 603 and intend to pull it sometime this week. I certainly won't miss the myriad of leaks from both the engine (front seal, lower IP seal, tandem pump, etc) and transmission. I've secured a ~6k mile rebuilt 722.3 with beefed up internals to sit behind this unit, so the entire drivetrain (short of an LSD upgrade) will be updated and hopefully leak free.

One new unknown regards what to do about the stock 606 turbo. These things are tiny and have a vacuum as opposed boost activated wastegate. The latter issue is relatively easy to rectify, but the small size is problematic, especially if more fuel is added. I'm seriously considering running tandem turbos in series, like this:



For simplicity sake, I'd probably just run with one intercooler. I'm thinking the stock turbo wouldn't have to be disturbed, and the primary unit would sit almost directly above. Not sure what size I'd use, but I think the trickiest part will be to get it to mount up securely, so that the plumbing doesn't bear the full weight of the turbo. I think it's obvious that just fabbing up a custom header with one properly sized turbo would be easier, but that's expensive and not really something I feel that I can do with my rather limited MIG skillz. I'm still working on this, so feel free to jump in and let me know how stoopid this sounds.

I still need to either have my stock IP sent off to Finland for the 7mm elements and external adjuster, or have the 6mm elements from the 606 IP swapped over. I prefer the former, 'cause I really want that external adjustability.

That's all for now.
 

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Few days ago I found a moderately priced LSD element for W124:
Elbe Engineering - W124/W201 LSD
That spring block is intended to increase the lockup of a limited-slip diff (either LSD or ASD), not convert an open diff into LSD.

I've installed a factory LSD in both my 1987 300D and 1994 E500, and I'll be happy to assist Casey when he's ready to go down that path... it was a fantastic upgrade for my 300D. The E500 already had ASR, so the LSD simply helps for racetrack use (no improvement on the street - ASR already works great on the street).


:thumbsup:
 

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Nice work! You are not going to throw that away are you :) Work has got me by the ears but I hope to get get by the shop on my way home today.
 

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Cruise Control
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Discussion Starter #10
Hey dude, thanks for the update. Let me know what you find at the shop. I'm getting ready to unload all sorts of OM603 stuff, including two trannies, an updated vacuum pump, modified intake manifold, #22 head (Dave has first dibs), injectors, glow system (relay, wiring and plugs), updated H2O pump housing and newer pump (beefier), etc.
 

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Sorry couldn't get over there yesterday and today I have training until 5 PM. Hopefully training will let out early.

I don't need anything right now for the either of the SDLs really. I will eventually but who knows when I can get around to it so I won't go there.

If you have a source for another 606 pump e-mail me please. Not in a hurry on that either though maybe this winter.
 

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Cruise Control
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Discussion Starter #15 (Edited)
Another update

I've stripped down the 603, and have the 606 on the stand. I had previously thought that the 606 engine was just a 603 block with a new head design; wrong. The whole thing is redesigned. The 603 has lots of gussets externally, but the 606 is smooth, with more volume inside the crankcase.

Also, the 606 oil pan has a built-in windage tray riveted to the rear section, while the front section is bolted to the main bearing saddles. I think I'll need to shorten the dipstick tube to clear the 603 pan. I really hope the oil pumps swap over easily. Also, the 606 pan has a drain section in the rear, not found on the 603, so the latter pan will need to find a way to allow drainage in that area, as well.
 

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Yikes! Not quite the simple bolt-on we thought it would be, huh. Glad you're taking the time to make sure everything is done right, and documenting the details... this should be very helpful for folks doing the uprgade in the future!

:thumbsup:
 

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Cruise Control
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Discussion Starter #17
I was beginning to think that I might be able to get away with running the 606 oil pump, as is...but once I test fit the 603 pan, it became clear that there were some issues. The pickup tube sits right on the bottom of the pan, and it's not bolted up completely. So, I'd really like to use a pump w/70k on it, vs the 603 version that has nearly 240k. I'll try just swapping over the pickup tube, which should allow me the clearance I need, while leaving a tighter tolerance pump in place.
 

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Cruise Control
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Discussion Starter #20
Yeah, if you look at the engine profile pics above, you'll see a notch in the front of the pan for the swaybar. The 606 pan doesn't have that notch and would hit the swaybar. I suppose it's possible that a 500E (V8) bar could offer clearance here, but I don't want to go backwards in that regard, since I have a larger "limo" version installed right now.
 
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