Date registered: Feb 2010
Vehicle: 1972 280SEL daily driver. 904 Dark Blue with cognac interior. euro 4.5 engine
Location: Williamsburg, VA
Mentioned: 3 Post(s)
Quoted: 34 Post(s)
Quick update. 13.7mpg on last tank all in town, so I'm back where I was prior to the conversion. I discovered the lock nut on the fuel pressure regulator I installed had backed off and fuel pressure was up to 50psi from the 43 I had set it at so I was running a bit rich. That does mess up a good bit of my tuning but I'm getting quicker at it. Hope to see better on the next tank but who knows. Can't wait to get her out on the highway.
Good news is that even with 50psi fuel pressure, no fuel leaks. I have so much more confidence in my billet fuel rails with o-ring seals to the injectors instead of clamps. I have eliminated 10 fuel lines under the hood (one to each injector, one to cold start injector, one to the damper) so that is 20 fewer potential leak points from failed clamps. Love it.
I think the next step is to start adjusting the Air-Fuel ratio settings to get everything running a bit closer to stochiometric. My leanest setting right now is 14.7 on high rpm lift throttle while a lot of my table is in the low to mid 12AFR. I should be able to get another MPG or two from it.