Jet Quesions
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Joined: Jul 2003
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From: phila Pa
Jet Quesions
I have a 750 holley that came off of a 383, I am put it on my 355, It obviously needs to be jetted down because it is too rich, My question is how do you know (whitout an air fuel sensor) when you are tuned in correctly, what are the tell tale signs?
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Joined: Sep 2005
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From: St Louis Missouri
There are a couple of ways to look into it without an A/F sensor, or an O2 sensor. One is to learn how to read the spark plugs. Run a search on Google and read three or more articals to get good info. Two are some tests you can do on the carb without the plunger attached. Here is some good info. http://wiki.corvettefaq.com/index.php?title=Tuning
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Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
Just because a carb was used on a bigger engine does not mean it will run rich on a smaller engine. In fact, with less metering signal, the carb will run leaner on a smaller engine. Jet the carb to its correct stock specs (per the list number) and tune from there if needed.
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From: phila Pa
Ok so last night i went down 3 Jet sizes and the carb seemed to run really well, However i took it for a test drive adn it was popping out the passenger side exhaust. Then the wierd thing. I jumped on it and a flame shot out the top of the carb, it was a rather large flame about 2 ft off of the top of the motor. Is this the Timing? as far as i am concerned The timing is dead on at 31 deg. In my mind i think that it would only backfire one way or the other. Exhaust or intake. This is what is making me think that it is not a timing problem. I am confused PLease HELP me to understand.
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Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
Originally Posted by 1971_CorVette
Ok so last night i went down 3 Jet sizes and the carb seemed to run really well, However i took it for a test drive adn it was popping out the passenger side exhaust. Then the wierd thing. I jumped on it and a flame shot out the top of the carb, it was a rather large flame about 2 ft off of the top of the motor. Is this the Timing? as far as i am concerned The timing is dead on at 31 deg. In my mind i think that it would only backfire one way or the other. Exhaust or intake. This is what is making me think that it is not a timing problem. I am confused PLease HELP me to understand.
