400 motor problems

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Mar 17, 2013 | 04:11 PM

400inatruck

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Joined: May 2011

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From: Wrights community

400 motor problems

On my 400, I have the EGR blocked off. I have the dizzy hooked up to a vacuum port on the intake. I have a Holley 2 barrel 2300 500 cfm carb. There is a miss and exhaust backfire on the passenger side and the back 2 cylinders are getting more gas than the front 2. I have the timing set and the carb tuned to where the driver side doesn't backfire. Any help is appreciated. Thanks

Mar 20, 2013 | 06:44 PM

mark a.

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Joined: Mar 2004

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No matter what you do a Holley 500 will not work right it will always be too rich. The Holley will 350 work great though.

Mar 22, 2013 | 02:10 PM

beartracks

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Joined: Nov 2000

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From: Albuquerque

500cfm is about the minimum size for a 400ci. If you still have the EGR plate under it it could be burned out internally letting exhaust gases into the intake.