300-24v vs 320
 

Hi guys

Still thinking about spending some money, I'm interested in the differences between the 300CE-24v and 320CE. Are the engines the only difference? If so how are they different. I'm in the UK, do I get more than the 220bhp in both I believe there is?

Are they both M104 engines, and if so, how many valves is the 320CE and why did they do this change?


later

Russ

i prefer the 24 valve straight six. v6's suck.

Tryan - The M104 3.2 liter engine was a straight six engine from 1993-1995 in the W124 chassis '93 300E (3.2) / '94-'95 E320, from 1996-1997 in the W210 chassis E320, and from 1991-1999 in the W140 chassis S320.

The 3.0 liter-24 valve M104 engine is an early version of the 24-valve DOHC 3.2 liter M104 engine used from 1993-on. The 3.0 liter version still used the CIS-E fuel injection system, using a distributor with one coil wire and 6 spark plug wires. This is basically a mechanical injection system with electronic control.

The "modern" 3.2 liter M104 engine was used in all U.S. 1993 and later 300E (3.2)'s, 300CE's, 300E Cabriolet's, 300TE wagon's, and '94-'95 E320's. Note that all 1993 300E / CE / TE's are misbadged as the engine is a 3.2 liter engine. The badging error was corrected starting in all 1994 models, but only the logisticians at Mercedes have the answer for this one.

The 3.2 liter M104 engine uses a different ignition system - HFM (hot-film mass air flow sensor), fully electronic with integrated electronic ignition and sequential fuel injection. This system combines fuel injection and ignition control in one module. HFM-SFI systems use coils that are mounted directly on the spark plugs, replacing the distributor at the front of the engine. Each coil pack provides spark to two spark plugs at the same time, one connected directly to one plug, and the other with a short high tension lead to the next spark plug. So there are 3 coil wires and 3 high tension lead wires.

HFM fuel injection systems are designed so that idle speed can't be adjusted. Idle speed is completely controlled electronically. This HFM injection system also has adaptive technology that compensates for conditions such as engine wear and unmeasured intake air and is designed to maintain driveability as the engine ages.

HFM-SFI can retard engine knocking to just the knocking cylinders, unlike EZL technology, which retards spark timing across the entire engine. This keeps the ignition timing point as advanced as possible for maximum power output.

The 3.2 liter M104 engines also have variable valve timing on the intake cam, making the torque curve broad and flat, developing HP at a much lower rpm. This makes the power much more useable and noticeable.

The early 3.0 liter 24 valve M104 engines are nice, but the advancement of technology is just so great in the 3.2 liter M104 engine, that if all possible, go with the newer engine.

tryan, why do they suck?
 

Any valid support for this

Note that some of the 1993 300E cars had the 2.8li M104, and were therefore badged 300E 2.8, as a logical replacement of the (M103) 300E 2.6.

I personally prefer the inline-6 to the V6, since they are inherently balanced and have a smoother exhaust sound. Too bad MB abandoned them.

thanks for the education suginami. from your post the 3.2 sounds smarter. i get to 'borrow' a 93 e once in a while and i love the motor in that car.

the v6 motor in the 99 wagon vibrated a little at idle. the 90 bank angle was a compromise to minimize tooling costs and the balance shaft just did not get it in my book. the secondary harmonics where quite obvious when you got on it. i will never get another car with a v6. they suck fuel like an 8 banger and have 4 cylinder power.

(plus the balancer fell off on mine, but i think the soft rev-limiter on the newer models will cure that woe.)

the torque specs for the v6 compare favorably to the straight six, but the seat of the pants dyno tells a different story.

300CE-24 vs E320C
 

I could be wrong, but I think the ORIGINAL post (from Russ) asked about the difference between the 3.0 liter 6-cyl 24 valve inlineengine and the 3.2 6-cyl inline 24-valve.

The 3.0 liter 6-cyl inline 24-valve (300E-24, 300TE-24, 300CE-24) was installed in the sedan, wagon, coupe and cabriolet around the late 92 to the late 93 production run on the models sited.

The M104 3.2 inline (not V-6) liter 6-cyl. 24-valve suplanted that engine from early 94 on.

There specifications are:

300E-24 / E320

Number of cylinders: 6 / 6
Bore x Stroke: 88,5/80,2 / 89,9/84,0
Total Displacement : 2,960 c.c. / 3,199 c.c.
Horsepower: 220 hp @ 6400 rpm / 220 hp @ 5500
Torque: 265 Nm / 310 Nm
Alternator: 14 V / 110 Amp -/-14 V / 90 amp
Battery: 12 V / 92 Ah -/- 12 V / 62 Ah

The 3.0 liter 24 valve was Mercedes "test run engine" for a multivalve power unit. This specific unit turned out to be as many Mercedes mechanics will say: "ALL noise - NO go".

As you can see, the 3.2 liter later on added more torque, and although they both had the same horsepower, it will reach peak power at less r.p.m.

I drove a 300CE-24 cabriolet for many months and I definitely remember the "all noise - no go" quality of the engine. When pressed hard, it will scream out like a cat mating, but the cabriolet would barely move from the standpoint. On the other hand, my E320T has a very nice pick up.

I have also heard some mechanics as referring to the "reliability" of the 3.0 liter 24 valve as "so-so", compared to a "very good" for the 3.2 liter 24-valve.

Re: 300CE-24 vs E320C
 

Excellent post, but in U.S. models, the early 3.0 liter 24 valve M104 engine was last used in model year 1992 models in W124's.

Model Year 1993 300E's have the new 3.2 liter or 2.8 liter M104 engine.
Those with the 2.8 liter M104 engine are badged 300E 2.8.
Those with the 3.2 liter M104 engine are badged 300E. The genius marketing people opted to not call this a 320E (as in the rest of the world), 300E 3.2 (to follow the U.S. pattern), or even E320.

Pentoman,

I drove a lot of 12v, 24V 3 litre and 24V 3.2 litre versions of the 300CE when I was looking to buy one.

There is no doubt in my mind that, good as the earlier versions are, the 3.2 litre engine is the one to go for.

It is MUCH faster (seat of the pants) , smoother and quieter and doesn't seem to be any thirstier......a win, win, win situation.

It's your money, but I'd want an earlier-engined E-series to be priced much lower to compensate for all that lost performance.

Thanks everyone
 

Thanks to all you guys, this is the advice I needed, technical info backed up by real-life impressions. I was erring towards the 300-24v before.. not sure why. But I will definitely go for the torquier 320 now (I love the torquey nature of my 190E's 2.0).

Of course, this is all if I can't find a 500E...

To extend on Mr. Gibbons thoughts: I have heard many people that would rather buy a 300E (the regular 12-valve 6-cyl.) over the 300E-24. Or, if your budget allows it, go all the way up to the E320.

Hey Russ, I have a 1990 300ce, with the M104, I love it!

Yes, the torque curve is not the same but, still pulls strong to 7000 rmp .

Remember these 3.0 M104's start in second gear thats why they seem sluggish, but Power Brake one just a little and nail the throttle, it will smoke the tires! Sometimes when I hammer it down into first gear, hit 7000, the tires chirp going into second.

My car has 130,000 and still drives like new. From what I have learned from this forum and my Tech, the 3.0 is GOOD, less to go wrong.

It's all good!

Russ, thanks for the tip's on the digital camera, I think I am getting the hang of it.

:)

300-24
 

hello, i have a cis 300-24 170.000 km runs like hell, i´ve tested it with 320 clk and no comparison clk "much a do about...
Perhaps differential and transmission, don´t know 320 specs about this.
Remember to overhaul the fuel distributor (new diaphragm!), i´ve done this to mine 6 months ago and it´s like new.
Enzo

If memory serves, the cabriolet is also about 500 lbs heavier than the coupe / sedan. That's a sizeable weight to carry around all the time. Then again, someone who drives a Civic or similar car will say any E-Class is too heavy.

No doubt the cabriolet is a very elegant looking model.

Since you're in the UK the 300CE-24 non cat is the one to go for.
The cat was optional up to 1993 and without it you get 230bhp and a lighter and simpler engine. You'll also avoid the wiring problems of the 320.