PeachParts Mercedes-Benz Forum - View Single Post - Has anyone ever used colder plugs with 87 octane gas

duxthe1 · #10 08-01-2010, 11:51 PM

Here at 5000ft, I run 86 octane all year long. My 103 has a true open hemispherical chamber and it tolerates it well, even on the most aggressive spark map. I always try to run the lowest octane fuel that any given engine will tolerate. There is more chemical energy in lower octane fuels, and they are more efficient. I am also a fan of water injection but the placement of the mass air meter in the 119 doesn't leave many placement options that will encourage even distribution and not kill the meter.

If your chain and rails are in good shape then playing with the cam timing isn't likely to produce positive results. I don't know this for fact but unless you own a dyno it would get real spendy to find out. I'd play with the heat ranges first and then see what you can get away with there.