About 6 months ago I had the Webers in my Caterham 7 (1700cc Ford Kent
crossflow w/twin 40DCOE's) re-jetted on a rolling road (chassis dyno for
North American English speakers). I was very happy with the result
except for under light constant throttle at about 2-3K rpm where the
engine seemed to be running too rich. But so long as I kept my foot in
it all was fine! :*)
The tuner used a Sun diagnostic system and looked to keep the CO ratio
around 5-6% under load and had me drive the car in between jet changes
to check the driveability and throttle response. It was an iterative
process that we went through probably 3 or 4 times.
Now that the weather is cooler the car doesn't run as well and seems to
run rich most of the time. My question is this: does anyone have any
experience in using a portable air/fuel ratio monitor to tune a car
under real road conditions? I would envision having a passenger along
to read the instrument and then stop periodically to swap jets as needed
and make a table of the correct jets for different ambient temperature
ranges. Any comments? Any recommendations on a air/fuel ratio monitor
to use? Thanks in advance.
Felix Klauser
Loral ASIC
Portsmouth, UK
(please note new e-mail address: felix@lfs.loral.com)
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