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Catch Can Making Car Hunt And Wont Idel

pimpenr33

By pimpenr33,
in Engines & Forced Induction

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OLik Contributor

OLik

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Make sure there are no reducers/step downs in the piping from the rocker covers to the can.

You want all the piping to be the same diameter as the hoses coming off the rocker covers.

i dont htink step downs are bad as long as they are sealed properly and not letting out air.

do not block the pcv valves on the rocker, they vent so there isnt a build up of pressurised air in the rocker.

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Steve Grand Master

Steve

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i dont htink step downs are bad as long as they are sealed properly and not letting out air.

do not block the pcv valves on the rocker, they vent so there isnt a build up of pressurised air in the rocker.

absolutely wrong - you can block the pcv on a turbo car, as the gasses just pass through to the catch can and then vent to atmo, or are plumbed back to the turbo>afm pipe

If you block the pcv, you may need to adjust the AAC valve so the car will idle correcltly though

RB engines breathe a fair bit, using reducers on the pipes to the catch can, or after the catch can, can cause crank case pressurising problems - but will probably depend on the degree of blockage, how fresh the engine is, and how much power you are making

best not to have any reducers.

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mad082 Grand Master

mad082

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does the catch can plumbing still have the pipe that goes to just after the afm? i have seen this pipe removed when people have installed catch cans so the motor is getting unmetered air.

if the new setup has a filter on the side that is sucking atmo air, not air from after the afm, then i'd say that is the problem.

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