View Poll Results: 300 vs 350 engine?
300 engine
19
23.46%
350 engine
62
76.54%
Multiple Choice Poll. Voters: 81. You may not vote on this poll
300 vs 350 engine? which one is better???
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
While I agree in that the loss in mpg offsets the lower cost of the fuel, you are going a bit (ok a lot) too far.
At idle the engine basically under very little load. A car tuned for 91 will easily idle on 87 without even a hint of detonation or pre-ignition. If he is loading the motor heavily, then yes, the computer will pull a bunch of timing. For normal driving, he will likely notice no difference.
At idle the engine basically under very little load. A car tuned for 91 will easily idle on 87 without even a hint of detonation or pre-ignition. If he is loading the motor heavily, then yes, the computer will pull a bunch of timing. For normal driving, he will likely notice no difference.
This is patent rubbish
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From: Rancho Cucamonga, CA
gets me from point A-B
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2017 E300
but really, nothing that you as a drdiver of maybe 5 years will notice. The car is modern enough to adjust to different grades of gasoline. you will be fine, and you will not notice the difference in performance or gas consumption.
though honestly, a .20 difference from regular to premium in a 16 gallon tank is a 4 dollar difference. brew your coffee at home and you are good to go
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From: Orange County
2019 AMG C43
STOP using 87, if you cant afford gas, sell your car and buy an accord/civic!
I have test driven a C350 and had a C300 as a loaner car and without a doubt you want the 350. It was frustrating how slow and bad throttle response the 300 gives. As compared to the 350, which is by no means a racer, provides enough power not to constantly **** you off.
Oh and i averaged(according to the computer) 25mpg in the 300 for the 2 days i had it.... umm i get 18.5 driving wayyyy more aggressively in my c55... fail
I have test driven a C350 and had a C300 as a loaner car and without a doubt you want the 350. It was frustrating how slow and bad throttle response the 300 gives. As compared to the 350, which is by no means a racer, provides enough power not to constantly **** you off.
Oh and i averaged(according to the computer) 25mpg in the 300 for the 2 days i had it.... umm i get 18.5 driving wayyyy more aggressively in my c55... fail
Last edited by SoCalC55; Sep 13, 2009 at 10:30 PM.
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Youngtimer
Well guys, I leased my IS250 in Jan. 07, when i had a good paying job. Now that im laid off, im pretty much broke so im forced to pump 87. Also, im just curious, but how big a difference is there from 87 -89 -91? 89 being the one below premium, but above regular. If im broke like i am now, would 89 be ok enough, or is not much better than 87? 
no point in posing in a benz when you can't even afford the right type of petrol. what are you going to do when you need an oil change? don't live beyond your means.
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From: Rancho Cucamonga, CA
gets me from point A-B
Well, since 87 is going to totally ruin the engine and its internal components...How about 89? its only one grade down from 91...so how would the car react? I know it will retard the timing and such, but is it still HORRIBLE compared to 91?
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Thread Starter
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Joined: Oct 2007
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From: Rancho Cucamonga, CA
gets me from point A-B
STOP using 87, if you cant afford gas, sell your car and buy an accord/civic!
I have test driven a C350 and had a C300 as a loaner car and without a doubt you want the 350. It was frustrating how slow and bad throttle response the 300 gives. As compared to the 350, which is by no means a racer, provides enough power not to constantly **** you off.
Oh and i averaged(according to the computer) 25mpg in the 300 for the 2 days i had it.... umm i get 18.5 driving wayyyy more aggressively in my c55... fail
I have test driven a C350 and had a C300 as a loaner car and without a doubt you want the 350. It was frustrating how slow and bad throttle response the 300 gives. As compared to the 350, which is by no means a racer, provides enough power not to constantly **** you off.
Oh and i averaged(according to the computer) 25mpg in the 300 for the 2 days i had it.... umm i get 18.5 driving wayyyy more aggressively in my c55... fail
But 25mpg is all you could manage? Im beginning to think the C class is very fuel inefficient. My IS250 is rated 21/29 and i averaged about 27 mpg (when running on 91)
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Thanks,
I'm sure that most, if not all, C300 owners manage better miles per gallon than I did; I was just posting my limited experiences with each.
Just as Zed said, if paying an extra $4 a tank extra on gas is going to be an issue then you're going to die when service B and even A come around.
Back on the 350 vs 300, take a trip to your local Mercedes dealership, tell them you want to drive a C300 & C350 with the same options and go from there.
I'm sure that most, if not all, C300 owners manage better miles per gallon than I did; I was just posting my limited experiences with each.
Just as Zed said, if paying an extra $4 a tank extra on gas is going to be an issue then you're going to die when service B and even A come around.
Back on the 350 vs 300, take a trip to your local Mercedes dealership, tell them you want to drive a C300 & C350 with the same options and go from there.
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From: Orange County, CA
GMC - Miata - Trek - P-Car
Next extended open-road trip you’re on it’ll likely approach or exceed 30 MPG. Mom's does.
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From: Irvine, CA
GLE 450 2021, SLK 350 2013, Honda Civc Type R 2019, Suzuki GSXR 750 2014, Ducati Diavel 2018
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From: Irvine, CA
GLE 450 2021, SLK 350 2013, Honda Civc Type R 2019, Suzuki GSXR 750 2014, Ducati Diavel 2018
yeah, I think everyone has been stressing on how important not using 87 octane rated gas. The manual recommends, if you must, fill the tank half way with 89 and then the rest with 91. It also recommends not driving with higher revs or fully loading your car.
Btw the gas recommended on the gas cover door is 95 with (91 as min).. Fill it up with 95 haha. just kiddings.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Firstly - American pumps state an Octane number close to the Motor Octane rating of the fuel where most of ROW state Research Octane. What this means in layman's speak is that what says 89 on the pump in the USA is in fact higher octane fuel than what says 89 on a pump in South Africa. Seen from the engine's perspective. What you see on the fuel flap is 95 RON Eurograde fuel.
To answer your question. Using 89 octane fuel in the high compression C300 will see the knock sensor detect the onset of knock everytime you load the engine. This will retard the timing which has an adverse effect on fuel consumption & performance. It will not damage the engine unless it get's to the point that the ECU cannot retard the timing far enough to prevent knock. Knock or pre-ignition can be destructive to a gasoline engine. A Benz can retard it timing sufficiently to prevent knock with 89 octane fuel. But why would you want to drive around with retarded timing - reducing the engines power output & increasing fuel consumption.
To answer your question. Using 89 octane fuel in the high compression C300 will see the knock sensor detect the onset of knock everytime you load the engine. This will retard the timing which has an adverse effect on fuel consumption & performance. It will not damage the engine unless it get's to the point that the ECU cannot retard the timing far enough to prevent knock. Knock or pre-ignition can be destructive to a gasoline engine. A Benz can retard it timing sufficiently to prevent knock with 89 octane fuel. But why would you want to drive around with retarded timing - reducing the engines power output & increasing fuel consumption.
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To answer your question. Using 89 octane fuel in the high compression C300 will see the knock sensor detect the onset of knock everytime you load the engine. This will retard the timing which has an adverse effect on fuel consumption & performance. It will not damage the engine unless it get's to the point that the ECU cannot retard the timing far enough to prevent knock. Knock or pre-ignition can be destructive to a gasoline engine. A Benz can retard it timing sufficiently to prevent knock with 89 octane fuel. But why would you want to drive around with retarded timing - reducing the engines power output & increasing fuel consumption.
Everyone, please read the bold words in the quote from Glyn. ENOUGH SAID!
That out of the way, why would anyone be buying a C300 or C350 if $4/tank makes a difference in the budget? You're buying the wrong car either C300 or C350. In my experience, the C350 is the more fuel efficient of the two. Whoever said Benz doesn't produce any "efficient" engines, again, ignorant. My M271 I4 is very efficient and in my week with a C350 loaner I saw 30mpg on the highway several times.
OP: Buy a cheaper car.
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From: SA
2008 C350-Sport-AMG-Active Agility Pack(Not reliable) +Izuzu KB6 3L(It seems Reliable)+Mazda
100-120Km/h
So far from my experience with C350 B170, both like to be rather driven at 100-120Km/h for lightest on feul. Reason I think is both have 7 gears, so no use you drive slow, and car not in 7th gear. C350 given 10.6L/100Km ove one year/20 000Km, slow and fast. Hills make a diff because it does not run in 7th.
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\
EDIT: Deleted lots of university physics
Here's a wikipedia page, running too low octane will cause abnormal combustion.
http://en.wikipedia.org/wiki/Engine_knock
So have fun ruining, I mean running, your car on 87 octane.
Last edited by Peabody; Sep 14, 2009 at 08:55 AM. Reason: additional clarification
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This is really fundamental physics, it's not rubbish.
You don't change the cam timing or stroke length of the engine by changing the fuel, you change the amount of work performed by the fuel.
If you don't know the first law of thermodynamics you really should troll posts on engineering. delta U = work + Q
One could post formulas like Q = C * m * delta T to show the effect of 6 degrees on a combustion or p * V = constant T to show how the reduced pressure of compounds the problem.. but I can see the issue is already over your head. So I won't bother posting on volumeteric expansion of gases, compression and heat, temperature required to create autoignition of vapors so fuel burns completely, and all that fancy science stuff.. you can just appreciate that I graduated from an aeronautical university and this sort of stuff was freshman year.
So have fun ruining, I mean running, your car on 87 octane.
You don't change the cam timing or stroke length of the engine by changing the fuel, you change the amount of work performed by the fuel.
If you don't know the first law of thermodynamics you really should troll posts on engineering. delta U = work + Q
One could post formulas like Q = C * m * delta T to show the effect of 6 degrees on a combustion or p * V = constant T to show how the reduced pressure of compounds the problem.. but I can see the issue is already over your head. So I won't bother posting on volumeteric expansion of gases, compression and heat, temperature required to create autoignition of vapors so fuel burns completely, and all that fancy science stuff.. you can just appreciate that I graduated from an aeronautical university and this sort of stuff was freshman year.
So have fun ruining, I mean running, your car on 87 octane.
says he to the man who spent a career working in the oil business.No one said you're not intelligent, Peabody, so don't get your panties in a wad. All anyone said was that your doomsday scenario about what will happen to a C300/350 on 87 octane is way too far out and not at all likely. For god's sake, they put regular unleaded in the loaner fleets at the dealership I use. It's not going to hurt the car and you're being entirely too dramatic.
I agree with the sentiment that $4 per tank is worth it for premium. We all do.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
This is really fundamental physics, it's not rubbish.
EDIT: Deleted lots of university physics
Here's a wikipedia page, running too low octane will cause abnormal combustion.
http://en.wikipedia.org/wiki/Engine_knock
So have fun ruining, I mean running, your car on 87 octane.
EDIT: Deleted lots of university physics
Here's a wikipedia page, running too low octane will cause abnormal combustion.
http://en.wikipedia.org/wiki/Engine_knock
So have fun ruining, I mean running, your car on 87 octane.
I got all your physics that you deleted & I understand them implicitly. Go back & read your incoherent post on a public forum. It's about as much use as **** on a bull to the general public. I think I know a little more about octane & octane tolerance/requirements of engines than you having spent a lifetime in the petroleum industry & more hours in dyno rooms than you've had meals. (this assumption based on the quality of your comments)
If you are capable of reading a little better than you express yourself you will note that I am not recommending using lower than required octane fuels. Octane requirements also increase as engines age & foul themselves.
I stand by my comment that, other than your quoted references, you are talking crap - this is why I separated your incoherent belligerence from the sense spoken by those you quoted.
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From: Toronto, Canada
09 C300S 4M
Go and test drive the 300 and the 350 and decide for yourself if the extra power is worth it to you. Everyone relates to power differently. Someone might think the 350 is a rocketship compared to the 300 and others will think the extra power does not justify the cost. It's a matter of personal opinion so get out there and give them a try!
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Listen Smart@XX,
I got all your physics that you deleted & I understand them implicitly. Go back & read your incoherent post on a public forum. It's about as much use as **** on a bull to the general public. I think I know a little more about octane & octane tolerance/requirements of engines than you having spent a lifetime in the petroleum industry & more hours in dyno rooms than you've had meals. (this assumption based on the quality of your comments)
If you are capable of reading a little better than you express yourself you will note that I am not recommending using lower than required octane fuels. Octane requirements also increase as engines age & foul themselves.
I stand by my comment that, other than your quoted references, you are talking crap - this is why I separated your incoherent belligerence from the sense spoken by those you quoted.
I got all your physics that you deleted & I understand them implicitly. Go back & read your incoherent post on a public forum. It's about as much use as **** on a bull to the general public. I think I know a little more about octane & octane tolerance/requirements of engines than you having spent a lifetime in the petroleum industry & more hours in dyno rooms than you've had meals. (this assumption based on the quality of your comments)
If you are capable of reading a little better than you express yourself you will note that I am not recommending using lower than required octane fuels. Octane requirements also increase as engines age & foul themselves.
I stand by my comment that, other than your quoted references, you are talking crap - this is why I separated your incoherent belligerence from the sense spoken by those you quoted.
I hope this sets the record straight. Use premium for your Benz. What you give up in MPG from retarding the timing will cost you just as much anyway. But don't buy into 87 being the juice of the devil that will cause engine destruction. It will not. Plain and simple.
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From: Seattle
C-300, XC70, Wrangler
I got the 300 because .....
I plan to keep the car a long while. I don't need the larger engine. I like the 28-32 mpg I get. It's actually on a par, driving cost and fuel efficiency, with my '96 Accord, when it was new. I like the car.
Um, so the other day I stomped on the loud pedal and was thrown back in the seat as the car smoothly moved through the legal speed limit and beyond. Not so easy to do that in an Accord.
I've been driving my Volvo for nearly a week. It rides better, but the C300 is far better in all other respects.
I plan to keep the car a long while. I don't need the larger engine. I like the 28-32 mpg I get. It's actually on a par, driving cost and fuel efficiency, with my '96 Accord, when it was new. I like the car.
Um, so the other day I stomped on the loud pedal and was thrown back in the seat as the car smoothly moved through the legal speed limit and beyond. Not so easy to do that in an Accord.
I've been driving my Volvo for nearly a week. It rides better, but the C300 is far better in all other respects.
