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pro86tourn
09-17-2020, 07:27 PM
Getting to the final stages of my build and in trying to get the car running right need some PCV help.

Stock bottom end LQ4, AFR heads, pro systems carb, vr. jr

I currently have the drivers side valve cover vented to a Moroso vented catch can and am getting tons of blow by out the vent.

I am going to add a breather to the passenger side valve cover... I also bought a LS6 valley cover with built in PCV (yet to be installed, I would like to avoid using the LS6 valley if possible as its uglier but no big deal I can paint it)

I have tried searching for the correct way to vent the engine but was unable to successfully find a carbed solution.

Any advice?

Thank you!

badazz81z28
09-18-2020, 08:20 AM
No different than a fuel injected engine...for PVC to work, you need a suction source, clean air in and dirty air out. On a FI set-up, clean air is pulled from the valve covers and dirty is pulled out at the valley pan. Your dirty air exit needs to connect to the carb to be burned. The question is, with a carb intake, I assume you still have a PVC valley pan? No? Connect that nipple on the valley pan to the carb and/or put a catch can between the valley pan and the carb to catch oil vapor.

pro86tourn
09-18-2020, 07:32 PM
No different than a fuel injected engine...for PVC to work, you need a suction source, clean air in and dirty air out. On a FI set-up, clean air is pulled from the valve covers and dirty is pulled out at the valley pan. Your dirty air exit needs to connect to the carb to be burned. The question is, with a carb intake, I assume you still have a PVC valley pan? No? Connect that nipple on the valley pan to the carb and/or put a catch can between the valley pan and the carb to catch oil vapor.

I currently have a sealed style valley pan on the car with no vent.

I have bought a ls6 valley pan but do they make block offs for the knock sensor holes? or is there a way I can use my current valley pan with no vent tube.

andrewb70
09-19-2020, 07:37 PM
Yes. Use one valve cover as the fresh air source and the other as the dirty side.