Thread: Vaccum Readings
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Old 01-27-2010, 01:19 PM
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Quote:
Originally Posted by Bernica View Post
I connected a good new vaccum guage to the 3/8" port in the carb baseplate. At idle, it is pulling around 10 lbs. As I accelerate, the vaccum climbs to 20+. If I jump on the throttle, it briefly drops, then starts climbing up again. I thought I should be losing vacuum as I accelerate.
Brand new Pro Systems 850 dp; cam is 236 dur .050 with .572 lift.
Am I missing something here? Or did I just sleep through that class??...
If the carb starts pulling vacuum again at wide open throttle, the carb is too small for the engine.

4 barrels are rated at 1.5 inches vacuum.

Or your air filter is too restrictive.
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