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Vacuum gauge observations (960) 900

Since we had a lot of extra pneumatic equipment at work (gauges, fittings, hoses etc) I decided to set up a permanent vacuum gauges in place of my non functional fuel gauge.
Idle is around 17" vacuum. 60mph on level ground is 12" 70mph is 10".
A couple of things surprised me. It takes very very little throttle input when accelerating to drop the vacuum to 3-5". At about 1/3 throttle vacuum drops to 0 at up to 4000rpm. At 6000rpm there is zero vacuum at 1/2 throttle. Moral of the story? Because the car has a light throttle and smooth engine I don't realize how fast I'm accelerating and how much gas I'm burning. When I tried driving by the vacuum gauge by keeping vacuum at 10" or more, the car is just plain slow. Acceleration felt more like the 240.
Another fun experiment was using cruise control and watching the vacuum bounce up and down. On pretty level freeway with the cruise set at 60mph, the vacuum gauge moved wildly between 20" and no vacuum. The cruise control seems to over compensate throttle input over the smallest hills just to keep the speedometer from moving 1 mph down. Very inefficient.

Next experiment will be to use a gauge that shows both vacuum and positive pressure in order to see if the ram air intake has any effect. Finding out is half fun. Stay tuned.






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New Vacuum gauge observations (960) [900]
posted by  someone claiming to be tjts1  on Thu Feb 10 17:51 CST 2005 >


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