It occurred to me the other day that the 50mile roundtrip t my parents house from my apt is costing me costs anywhere from 8-10 dollars.

Now I remember that Jurgen Shrempp and the 90's were the nadir or Mercedes engineering, but I never really bought the twin spark SOHC setup except as a way to save money.

EPA info:
C320: http://www.fueleconomy.gov/feg/noframes/16663.shtml
330i: http://www.fueleconomy.gov/feg/noframes/16588.shtml
A4: http://www.fueleconomy.gov/feg/noframes/16576.shtml

Actually the A4 has the lowest displacement and worst MPG but AWD does add drag.

Judging my Mercedes engine tech vs the competition, i'm sure that in the 90's there was a mass exodus to talented engine guys from Stuttgart to Ingolstadt and Munich.

 

The twin spark was not for fuel efficiency it was for better power and exhaust numbers. I can get up to 31-32 MPG if I keep my foot out of it and drive somewhat eco friendly.

 

+1

I've been in the low 30's with the AC on before. 32 is the highest I've seen on mine.

 

I do recall that in theory the 3 valve twin spark design was supposed to heat up the catalytic converter. But more power? Even in 2k1, 215hp from a 3.2L engine wasn't anything to brag about. Someone in my family had a V6 Honda Accord 3.2L SOHC 4valve VTEC that generated the same HP

It wasn't till the M271/M272 that they got their act together. But even still, Ingolstadt and Munich engines IMO are more advanced. Mercedes-Benz still doesn't offer Gasoline Direct Injection though out the line.

 

The M112 was built as a LEV vehicle engine & blows one of the cleanest exhausts of the period. Benz has always been conservative & built for longevity. Considering the weight of the vehicles the fuel consumption is fine. The M111 was an old engine design with Kompressor attached & always heavy on gas. But it's tough as hell.

 

Add one more to the 30+mpg M112 club...

On one leg, which was exit-to-exit on the interstate between fill-ups, I documented 32.5 mpg...

Around town, upper teens.

 

hmm out of curiosity, are you guys using the on board computer to monitor your gas consumption or do you solve with good old math?

my on board computer says i average 19, with 14 around town.

 

Talk about a heavy foot.

I managed to get 27 on the highway.

Strangely enough, without a hood, I get somewhere around 32-33. Don't ask.

 

when I do calculate the mileage I usually do it both ways computer and "math" That said usually the computer is only .1-.4 or so under my true mileage. Since my car has had the Tune I have not been getting my 30 MPG any more but that is mostly due to me driving more aggressive and enjoying the sound our m112 makes at 5k lol
Going to work I usually average 8-12MPG depending on how many lights I hit but that is 2 miles of stoplights mostly so what do you expect.

 

I do it both ways as well. Just take the amount of gallons filled divided by mileage travelled. It's usually spot on.

I always forget that W203's weighs so much since it's a compact car (in the USA). The brochure says that the curb weight is 3395 lbs. Anyone know what the weight is laden?

I always thought that Mercedes-Benz was on the cutting edge of technology. Between heritage, and pedigree, Mercedes-Benz always seem to brand themselves as on the cutting edge. Seems that every other manufacturer were able to meet LEV and even ULEV standards in 2001 with MUCh better power numbers.

Case in point. 2001 Acura TL Type-S with the J32A2 engine. Displaces 3.2L, SOHC w/4 valves, pushes out 260HP AND IS [B]ULEV[B]
http://en.wikipedia.org/wiki/Honda_J32#J32

As a result i'm really disappointed with the M112 engine in terms of specs. It's a 90degree Vee, with mediocre numbers. I agree w/the bulletproof assertion since it has forged con rods. Is the crankshaft forged as well?

I found this little blurb on the rationale for twin spark plugs.
http://www.autozine.org/technical_sc...mpression.html


What redeeming values does the M112 have over the Honda ULEV J32A2

 

most of my driving goes to uphill =(

thus the poor gas mileage. on the way down, im getting a lot more as i just cruise.

 

The last time my car went to get its emissions checked, the car was weighed in at 3390lbs.

Im no pro w/ motors, but...

The TL motor has greater economy w/ FWD and Cylinder deactivation
The TL motor makes greater power w/ Vtec?

All things the m112 doesnt have! woo!

 

i have the m271 engine and the most i got was 35.0 mpg...but since my air filter is dirty to the max i get like 25 hahahahah

 

Honda makes excellent engines & always pushes the power envelope for power output naturally aspirated - but this is at the expense of refinement. The Honda can become quite rorty when pushed which the Benz is not. I love Honda engines so I'm not knocking them - just a different attitude to acceptable NVH. As Tru says the efficiency of FWD helps them too as does weight in the fuel efficiency stakes.

The Benz M272 quadcam (developed from the 112) was already on the drawing boards at the time of the W203 launch in 2000. The M112 was in it's final model range & had been fitted to previous models. The very reason I bought my car. I wanted a tried & proven drivetrain & it has been faultless. Good as Honda's are they won't do the mileage a M112 will. A friend in KL Malaysia has just sold one of his 2003 C240's with over a million Km's on the clock with no major repairs. (airport taxi service for the Regent hotel)

As I have said before, Benz is always conservative with it's standard engine offerings. The 112 is ultra smooth for a 90 deg V & lasts forever. It was no slouch in C32 form of course. BMW & AUDI engines will do nothing like the mileage without crap.

The crank is cast & plasma nitrided as with the cams (not C32 - they are hollow/pressed), the rods are forged. The twinspark rationale by Benz was flame front propogation & emissions driven. Materials technology is interesting in these engines. (from rings to iron coated pistons to alusil bores etc.)

The redeeming values of the M112 are refinement & longevity without complexity. If you want complexity then buy a wonderful M272. Take a good look at the heads & cam timing arangement. Great but complex. I always notice a slight grittiness in the M272 but it is very slight & more pronounced on the 350 - A Honda driver would wonder what the hell I was talking about.

 

My M111 avgs 27 with a combined city and fwy. On fwy drives I can get up to 34 mpg. When I start hypermiling, or drafting large trucks, it can really go up.

Ed

 

I forgot to mention that I *do* have an ECU tune which from my observations bumped me up 1-2 mpg.

This last weekend on a two and a half hour road trip to KC I was up to 37.2 mpg on the display.

 

27 mpg would be only at freeway driving 60mph for me. How do you get such good mileage?
The only time i saw 34mpg was going downhill from Tahoe to Sac on 80.

 

I've managed as high as 33 overall on a trip between Atlanta and Willamsburg, VA, with two adults and luggage in the car, staying a solid 75-80 on the Interstate but being easy with the throttle.

My normal around town with a mix of freeway and surface streets is about 22, and that is with my normal driving. My average, overall, over the last 604 Gallons was 22.9 mpg. My wife in the SLK, over the same period was 137 Gallons and 26.6 mpg -- but hers was only one highway trip, the rest within about 10 miles of the house.