I switched to regular (87 octane) gas - Page 2 - PeachParts Mercedes-Benz Forum

gatorblue92 · #16 10-29-2016, 07:18 AM

I'm only running premium in my 91 300TE. The M103 called for premium and its run for 272k miles on it so why change now. I only need to fill it up every few weeks since its not a DD so the extra for premium doesn't hurt as much.

I will say I tried premium 93 octane for a few tanks in my 2015 F150 with the 2.7 TT EcoBoost and it seemed like there was a bit more power than with regular 87. No noticeable difference in economy though.

Frank Reiner · #17 10-29-2016, 09:00 AM

Quote:

Originally Posted by Mxfrank

Static compression ratio is one thing, and dynamic compression ratio is something else. Dynamic compression ratio is measured from the point the intake valve is closed, which is well past BDC. Cam timing is critical in determining the octane requirement for the car.

In plain English: knowing the static compression ratio of an engine isn't enough to know whether premium is required.

And there it is; compression pressure is the determinant for any given combustion chamber configuration, rather than compression ratio.

anziani · #18 11-05-2016, 12:14 PM

Kestas, don't ever get a CL600. You will have a stroke with its 27 gallon tank and premium gas requirements. Do I give a rats ass? Hell no, it is a motorized rocket with a 12 speaker sound system. Will never have another like it.

Anziani
'97 CL600 62K