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On 15 Nov 2001, at 17:48, Erkson, Toby wrote: > "...cars which pollute less, use more gas." i.e. the last sentence ;) > > FI is better than carbs for reducing emissions as well as increasing gas > mileage. That's where my confusion lies...lays...is... :) Okay, gotcha. I don't know why this should be true, but here are just a few datapoints from my experience. Across the 6 years of the type 3 EFI the gas mileage our cars got came slowly down as the emissions regs tightened. I ASSUME that our cars polluted less as this happened. In general, I hear gas mileage figures for OE dual carb type 3s that are better than what I expect to see for the EFI cars that I am familiar with. Mike Wodkowski's 72 seems to be a counterexample of this, but I'm at a loss to explain it because he's driving MY old engine with MY complete old EFI setup. While I tend to discount many of the high gas mileage reports to limited data (a single tank, poor measuring conditions) or just owner enthusiasm, I can't ignore all of it. I suspect that your gut feeling agrees with mine: Efficient use of gas should lead to more perfect combustion and less pollution. Clearly some of today's cars get much closer to this ideal than our cars and maybe there are modern concepts that could be applied to our engines, like combustion chamber shape. But I think the air cooled engines often come up agains NOx production limitations that force us to run rich in order to keep combustion temps (and NOx production) down. Another point here is that during the early 70s, as emissions regs were really clamping down, the gas mileages of all cars that I was familiar with seemed to be slowly declining, if you stick to comparing the same model cars with the "same" engine, but just different pollution control measures. OTOH, this was just about the worst period ever for cars, as the automakers had little experience worrying about either gas mileage OR emissions, and the results were generally pitiful. Again, this is just my impression. - Jim Adney jadney@vwtype3.org Madison, WI 53711-3054 USA ------------------------------------------------------------------- Too much? Digest! mailto:type3-d-request@vwtype3.org Subj=subscribe