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-   -   need some advice. (https://www.racingjunk.com/forums/showthread.php?t=32513)

fast75vega 08-19-2012 02:59 PM

need some advice.
 
ok.. got a question? can i run the valve cover breathers to the bottom of my air cleaner like the old chevy use to use and use the carb vacuum or do i need to run a vacuum pump or down to the header collector.... just wanna seal up the rings and dont have the money for a pump right now. just need to know if anyone has tried it and if it will work?

coloradoracerguy 08-19-2012 04:46 PM

Running the breather hoses to the air cleaner will do nothing. The factory did that for two reasons. One, to make sure any air drawn into the crankcase was filtered, and any blowby that the pcv could not ingest would be ingested by the motor at the entry to the carb. In a performance or race application, it's basically useless. If you need to pull a slight vacuum in the crankcase to help with ring seal, make sure you have backfire valves on the headers and run the tubes from the valve covers to the collectors. If there is an exhaust system after the headers however, don't even bother as the backpressure will defeat the purpose of the vent system.

Is this a race only or street/strip deal?

fast75vega 08-19-2012 04:55 PM


Originally Posted by coloradoracerguy
Running the breather hoses to the air cleaner will do nothing. The factory did that for two reasons. One, to make sure any air drawn into the crankcase was filtered, and any blowby that the pcv could not ingest would be ingested by the motor at the entry to the carb. In a performance or race application, it's basically useless. If you need to pull a slight vacuum in the crankcase to help with ring seal, make sure you have backfire valves on the headers and run the tubes from the valve covers to the collectors. If there is an exhaust system after the headers however, don't even bother as the backpressure will defeat the purpose of the vent system.

Is this a race only or street/strip deal?

its drag only..... straight headers!

fast75vega 08-19-2012 05:12 PM

can i tie into the intake plenum for vacuum .... i planned on using pcv fitting in the valve cover rather then the breathers i have in there now.

wazup 08-19-2012 07:12 PM

No when you open the throtle there is going to be no vacuum. When at an idle i doubt that you have very much vacuum. The best way is with the crank case evac system its only about 35.00 and little welding and hook up hoses to valve covers and your done. I run them before and they work pretty good, hope this helps.

Good luck


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