Thread: Low on power?
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Old 09-09-2022, 09:35 AM
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Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
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Quote:
Originally Posted by cobragene View Post
I did check again yesterday, looking at the butterfly’s they are opening fully. Would my old air filter element which is shorter create more vac to open secondary’s more? I want to try that but it’s off the road for a few more days. Thank you for your help
Yes, restricting the air flow to the carb will actually make the secondaries open sooner. That's why you often read threads on other forums where guys buy expensive free-flowing air cleaners and then complain that it made their car run slower (because the secondaries are no longer opening). Of course, for best performance you want as much free flow as possible and then tune your vacuum secondaries to open properly based on the new venturi vacuum values. One simple and easy test is to wire your throttle in the wide open position and then reach over to the vacuum secondary and with your finger push the plunger up in to the housing and see if the linkage feels reasonably smooth. If you were able to put your fingers down to cover the holes that lead from the venturis to the vacuum secondary canister you could then let the plunger loose and it should stay put. But doing that requires three hands. If the the plunger did not stay put that would indicate a leak in your diaphragm or maybe the little cork gasket.
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