I have to ask this question; I can't seem to find a straight answer on the board.

There may be a 603 swap in the future for my W123 - after weighing the cost of a Myna pump and other performance mods.

Newer engine technology may also yield better economy results. Doesn't a OM606 get around 30MPG and have well over 150+HP, stock?

Not that I really want to deal with a computer controlled engine, but a 606 does sound nice. (WAY out of budget! ;))

In lieu of that thought, I would like to know.. what can a 603 yield as far as power and economy?

Also, what transmissions were available? Any manual gearboxes?

Can some of these great innovations such as variable geometry turbos (VGT) be fitted to them? Two stage injectors? Intercooling? What modifications can be made to the fuel delivery system to provide more fuel?

Things like that, any input appreciated. Just.. anything short of sending it to Finland. :D

In lieu of that thought, I would like to know.. what can a 603 yield as far as power and economy?



The general consensus with the stock pump is 200 hp with a suitable intercooler. Economy is not affected unless you drive it hard. Typical economy remains at 26-31 mpg depending on vehicle, and driving habits.

Aren't there issues as regards stuffing the 603 block into a 123 chassis?

Aren't there issues as regards stuffing the 603 block into a 123 chassis?

Sure, there always are. Off the top of my head:

Engine mounts
Speedo compatibility issues
Throttle linkage to chassis
Driveshaft length

However, it looks like it will fit without much fuss:
http://www.w124performance.com/images/SuperTurbo/W123-OM606/engine01.jpg

Is myna selling starter packs yet?

Is myna selling starter packs yet?

Starter packs?

Sure, there always are. Off the top of my head:

Engine mounts
Speedo compatibility issues
Throttle linkage to chassis
Driveshaft length

However, it looks like it will fit without much fuss:
http://www.w124performance.com/images/SuperTurbo/W123-OM606/engine01.jpg

Funny looking 603. :D

I like how the "performance" filter has been crushed in by the suction.

Starter packs?


Yeah, like a beginner kit.

IP, IC, tubing etc. bolt on HP :D

Funny looking 603. :D

That is because it's not a 603. It's a 606. Just illustrating a point, aren't the two relatively the same size?

That is because it's not a 603. It's a 606. Just illustrating a point, aren't the two relatively the same size?

Everything is virtually the same. Except for the plumbing of that huge DOHC head, intercooler, manifolds, etc. I believe it's possible to transform a 603 into a 606 (the main drawback being the accomodating 4-valve piston cutouts). Too bad you couldn't use the 3.5 liter with the 24-valve head. That would be the ultimate OM60x.

Too bad you couldn't use the 3.5 liter with the 24-valve head. That would be the ultimate OM60x.

Why not? If the 3.5 head fits the 3.0, why wouldn't the 24 valve 3.0 head work?

-Jason

Why not? If the 3.5 head fits the 3.0, why wouldn't the 24 valve 3.0 head work?

-Jason

Potential for an impending doom.

I could get behind that. :D

Why not? If the 3.5 head fits the 3.0, why wouldn't the 24 valve 3.0 head work?
It's theoretically possible, but the cost and effort required is totally not worth it. If you want a 606 turbo, buy a complete 606 turbo engine. You'll have a really hard time finding a complete 606 top end for sale cheap to experiment with plopping it on a 603 block. I've heard of 606.96x engines in good condition for $3-$4k...

:stuart:

Doesn't a OM606 get around 30MPG and have well over 150+HP, stock?
Stock power is 148hp from the 3.0L, 200lb-ft of torque. The MPG depends on the chassis and gearing. Best you'll likely ever see is in a W124, at 32mpg, anything past that requires extra gravitational pull from the moon, or lots and lots of downhill driving. More common is 26-29mpg. Some more power specs for various years, engines, etc is at this link (http://www.w124performance.com/docs/mb/other/acceleration_specs.xls).


Not that I really want to deal with a computer controlled engine, but a 606 does sound nice. (WAY out of budget! ;))
The Finns use a 606 engine with a mechanical 603 pump. Straight swap other than getting creative with throttle linkages. Forget trying to run it electronically in an old chassis (123, 124, 126).


In lieu of that thought, I would like to know.. what can a 603 yield as far as power and economy?
The power is limited by your budget. The stock pump is wheezing and coughing by 175-180hp (at the crank). 6mm elements might get you to 200-220hp (not sure exactly, nobody has done it yet, but I'm working on it.) Myna can get you to 450hp on a 603, or 500hp on a 606, provided you have enough airflow and intercooling capacity. Figure $2000 for the Myna pump, including shipping both ways.


Also, what transmissions were available? Any manual gearboxes?
99% are automatics. The 722.3 tranny can be built to withstand 500hp and 500lb-ft and survive. And, numerous tranny builders can do this. For a manual box, you're on your own - good luck. A manual also has the problem of losing boost with each lift-throttle upshift.


Can some of these great innovations such as variable geometry turbos (VGT) be fitted to them? Two stage injectors? Intercooling? What modifications can be made to the fuel delivery system to provide more fuel?
VGT, yes, but you're talking full custom plumbing, and custom computer controls. I've seen a dyno graph on the Schuman forum that was amazing but I think the controller alone was like $3k. Two stage injectors, not sure, I don't think the Finns are using anything other than stock injectors. If it works for them, I wouldn't re-invent the wheel. Intercooling, that's up to you... depends on your power levels, how much room there is in the chassis, if you are willing give up the AC condenser, etc. The fuel delivery system should be adequate, worst case you might need a "pusher" pump back under the tank, but I doubt it.


:zorro:

Dave, I have to say, you're a fountain of good information!

Loosing boost isn't too much of an issue to me, a gear box with a wider range will allow me to fab taller gears into the rear end, but give a wide enough range to provide performance in the lower gears and economy in the higher ones.

Pros > cons in my book. And beside that, it'll give me an excuse to install a pointless blow-off valve to scare ricers.

Who sells complete engines that will fit in my 87 300 SDL (126)?

Metric Motors (http://www.mercedesengines.net/) and Mercedes Benz are two that do.

Ditto that... Metric and the dealership for rebuilt engines. You can buy the factory crate motors from other vendors as well (Rusty, etc) but don't forget most will want a core motor in return. Although Adsitco may also advertise engines, I'd avoid them like the plague. Rebuilts will likely run you $6-$10k or so for a long block.

If you want a complete used engine, there are typically a dozen or so available, depending on the miles, etc. Potomac Pat has a couple available at the moment, one low miles, one high miles... typical used prices are $1.0-$2.5k.

:scholar: