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catch can on vn 304

bigstu

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Hey guys looking at putting a single catch can on my 304 main reason is I like to rev it over 6k.So anyway just after some info.Ive got one that has two fittings and the filter on top,So the question is am I able to just redirect the hose from the front of both the rocker covers to the can and block off where the hoses originally went to on the throttle body.any answers on this would be great,Thanks guys
 

Darren_L

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you can do it that way and a lot of people do
but it's a defect waiting to happen as you are allowing the crankcase fumes to breathe to atmosphere

also I prefer the crankcase breathers to be drawn out by engine vacuum (as per factory setup). You won't remove the engine vapours/fumes anywhere near as effectively without the assistance of vacuum. Oil will degrade a lot quicker without it. I've retained the factory setup, just installed a sealed catch can between the pcv (passenger rocker cover) and the throttle body vacuum line. I've left the drivers side rocker cover breather as it was. Works perfect and is street legal.

Also make sure your catch can has an internal oil separator (baffles) otherwise it won't be very effective. I actually pulled my catch can apart, fit a divider between the inlet and outlet and filled the chambers with stainless steel wool.
 

wraith

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Yeah the ebay special catch cans are just a can and not very effective at all. Darrans idea works well.
 

shaun001

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on mine i ran 2 dash 10 lines from the catch can to the stock rocker cover fittings, with one of them reversed so they both face the same direction then uesd speedflow cover clamps over the top and blocked were the pcv line was
 
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