95 SL500 What Octain Fuel must we run?
 

First Benz here. And I LOVE IT! :D I just bought this car for my wife. A nice Christmas present. I asked her what her favorite car inthe world would be to own, and without but a few seconds she responded a Mercedes Benz SL500. It simply is her favorite.

So I did a lot of research, thanks guys I read a lot of your posts, and found a 1 owner car with 50k in perfect condition.

What I didn't expect was the awsome level of performance this thing offers. :sun_smile The trip home was a real eye opener for me.

All Spring, Summer and Fall I race two C5 Corvettes in SM-II. That is basically an unlimited Modification class. it's safe to say that I'm used to some serious power. ;)
http://www.peachparts.com/shopforum/...id=22246&stc=1
But I didn't think that this car I bought for my wife would hit nearly as hard as it does. Nice smooth delivery of torque. Shifts wonderfully well. Doesn't break loose like the Vettes. Just a good car.


Now back to my question:

This is her car. i'll only be driving when we use it to go on trips and such. She drives slow. Like very conservative. The car will never have the go pedal passed the 60% level.

With that said what octain fuel will she need to run?

91 or above. Doesn't matter how she drives. Welcome to the R129 Group!

S

95 or above?
 

Hmm - 95 or above was written on my SL fuel filler cap. The engine changed in 95 to the 24-valve head. Perhaps that dropped the octane rating. However, my new CLK500 is also marked 95 or above. Is there a difference betwen US and European octane ratings? Don't think so.

Momo

Is your Euro fuel unleaded or the good stuff (leaded) that is so hard to get in the States? That will make a significant diff in the octane ratings.
Al

Type of fuel ???
 

I have three vehicles(96-S-320, 97-SL320 and Volvo S-90) which call for high test (91 oct). I have been using mid-grade(87) since new with no ill efects at all. I've been told if you don't dog the vehicle, this is fine. As long as It does not ping or diesel at shut-off, no problem. With all the new electronic controls on todays cars, the computer will automatically adjust the timing to control knock, ect. These vehicles get the following mpg on road trips: 96-S320=27 mpg, 97-SL320=24 mpg and Volvo=23.5 mpg. The Volvo should do much better, but they do not use lockout in high gear, so every time you let up on the gas, it down-shifts(piss-pore xmission setup). Good luck

The euro cars have higher compression and more power. Well at least they used to now they probably just change the computer program. 91/93 is about as good as you can get in the states.

European octane ratings are the RON number. US ratings are an average of RON and MON also known as the pump octane number. 96 octane in europe will correspond to approximately 92 octane in the US. The reason for the different numbers is the different test methods used.