It would be much leaner. A lot of guys I know who with carb'd vehicles who really care about hp have spring/fall jets and different summer jets, most stuff is put away for the winter here but that would require a 3rd set of jets.....I always tell them that's why they invented EFI
i think altitude and/or heat makes the car run richer, doesn't it? in both instances, the air is less dense. Hans...for sure you'd be running on the mains at that speed. seems to happen at about 110kph....maybe a little over, depending on conditions that puts you in a very awkward position. if you tune it to be economical at that speed, i don't see how you could get full power. on the other hand...i might be completely wrong
Yes of course, richer….I had my head on backwards, sorry. The equation for a venturi is Change in pressure = (Velocity2^2-Velocity1^2)density/2 That says the pressure change is directly proportional to the density of the air. The equation for flow the fuel flow with pressure change is: Flow2 = Flow1 * (P2/P1)^0.5 That says that the change in flow rate is proportional to the square root of the pressure change so the mixture changes. When air density goes down, the fuel flow rate only goes down by the square root of the density change making the mixture rich.
OMG....that explains it anyway...i was quite careful that i did my testing during cold weather at sea level. i don't mind the car running a bit richer.....but i wouldn't like it to get any leaner.
110 kph? I never drive that slow! I guess I'll have to try to lean out the mains for slow cruising and simply live with the fuel burn... Too bad that fuel prices went up again. We're now at US$9 per (US) gallon...
