Evening All,
Thanks for the gen, Bob and Egil.
The PI was broke in the first place in that I was getting 16mpg with fairly
sedate driving and the plugs a tailpipe were unarguably black!
The first adjustment gave me 21 mpg, still with black plugs and tailpipe; I
suspect that the mixture was spot-on at tickover but was over-rich at road
revs.
Egil, I didn't make myself clear. The irregular misfire denotes the mixture
setting which passes emissions tests in the UK. It is not a problem as such.
I've now figured that the datum track rotates around a fixed point, so
adjusting it must alter the mixture proportionally, i.e. the difference made
by setting the top gap is reflected to a smaller degree when the rollers are
at the bottom of the track. Equally, the difference between lean, correct
and very rich is a very small adjustment.
I appreciate the point about testing the gaps up the vacuum range but the
adjustment is surely too coarse to make a significant difference at the
points on the table. Is testing the tracking up the range more a matter of
checking than adjustment?
As it stands, the car pinks under very heavy acceleration but otherwise is
running better than ever. The mid-range power is noticeably improved.
Bearing in mind that petrol in England costs nearly $5.50* (UK£3.54) a
gallon (over 83% being tax), would it be better to run the car as it is,
perhaps retading the ignition by a degree to prevent pre-ignition?
I stand to be corrected on this but I would expect about 25 to 30 mpg from
my car. How much fuel do other people's cars use?
Thanks again, Dave Hill
* I think this is right. Maths is not my strong point:-)
|