just a quick question, and i did search it briefly. . .but would 100octane in the cls55 make any difference, or is it pretty much tuned from the factory for 91-93?

thanks in advance!

 

frankieb96 - Pretty much as you mentioned, however if the gas you have been using is of poor quality then yes you will feel a slight difference. Also, if the weather is cold, higher octane will help a little to take advantage of the denser air, given the ECU has any timing left in it's operating parameters to throw at the situation.

Now, if you have a pulley and some ECU tuning, then yes for sure, if the ECU tuning was set up to take advantage of the higher octane! It's all about moving Peek Cylinder Pressure closer to Top Dead Center to take mechanical advantage, as much as possible, of this Peak Cylinder Pressure event. - - Bob

 

thanks bob. . .kinda what i figured, but i needed to hear it from someone, haha

im fortunate to have pretty good quality stuff here in orlando, and i can drive 5 min from my house and get 100oct right off the pump at Sunoco, i was just pondering it. . .

EDIT: forgot i had a camera phone pic. . .was just messing around cuz my friend put a half tank in his car(E39 M5)

 

Nice M3, don't care for the new body style.

 

thank you. . .as for the new M3 - i havent seen a "finished product" yet, so im keeping my fingers crossed that it will be decent *stylistically*, but i'll put my money on the fact that the engine and gearbox will be phenomenal

 

Correct me if wrong, but higher octane fuel helps FI cars, especially the turbo cars.

 

Hell yeah! With a 100 octane you should feel a difference as soon as the fuel circulates! That should be quite fun, but be careful with that. I've seen people blow engines (admittedly not in a Mercedes) fooling around with hi-po "petrol".

M

 

Only if the car is tuned for it, otherwise it's a waste of money.