What About These AFR Numbers?

[rwest]

I've been trying to get my car running as well as possible; 1977 911S with CIS. I did an extensive refurb last year of the CIS and at the time my WUR and fuel distributor where in spec and I also tested as many of the other bits that I could and they tested out as well.

I still think there is room for improvement; it feels like a very, very slight bucking sensation at low RPMs and a steady speed- really hard to tell if it's the engine or bumpy roads, that's how slight it is.

I had a bit of ignition trouble last fall and I now believe that I have it all sorted, so I hooked up my LM-2 with the tailpipe adapter and headed out on a 50 mile drive in 80 degree temps.

Car never got above 200 degrees. Here are my observed AFRs, what do you think?

Idle 12.8 cold 13.1 at the end of the trip.
Full acceleration 13.8.
Steady cruising on flat road at 55 mph 14.4 to 14.7.
Slight acceleration 15.4 to 15.6.

Thanks for any input or suggestions.

[fred cook]

Idle 12.8 cold 13.1 at the end of the trip.
Full acceleration 13.8.
Steady cruising on flat road at 55 mph 14.4 to 14.7.
Slight acceleration 15.4 to 15.6.

The idle AFR looks to be too rich while everything else looks to me to be ok. If your fuel mileage is acceptable, I would leave it alone!

[wreckah]

full acceleration should be quite a bit richer no? more like 12.5 or so...

every car is a little bit different, my car idles nicely at 13.5.