63falconATX
Well-known member
Been tuning and have come to the conclusion the stock PCV might not be right for my hopped up six.
Stock bore and stroke E0 200
Aussie 2v head, stock valves, 1.6:1 rockers
Re-cureved HEI
6/2 headers
Holley 2300 350 cfm
274/274 110 degreed 7.5*
Measured/calculated 8.9:1 cr
We know we have higher manifold vacuum at idle and the PCV spring should allow increased airflow at higher RPMs when vacuum is low.
Simple test, tissue over the breather hole opposite the PCV, tissue pulled in at idle. When RPM is increased the tissue is no longer pulled inward. Over ~2800 RPM it is actually blowing off. It is simply not keeping up with crank case pressure.
This seems wrong to me. I'm thinking the build might need a PCV other than stock?
Stock bore and stroke E0 200
Aussie 2v head, stock valves, 1.6:1 rockers
Re-cureved HEI
6/2 headers
Holley 2300 350 cfm
274/274 110 degreed 7.5*
Measured/calculated 8.9:1 cr
We know we have higher manifold vacuum at idle and the PCV spring should allow increased airflow at higher RPMs when vacuum is low.
Simple test, tissue over the breather hole opposite the PCV, tissue pulled in at idle. When RPM is increased the tissue is no longer pulled inward. Over ~2800 RPM it is actually blowing off. It is simply not keeping up with crank case pressure.
This seems wrong to me. I'm thinking the build might need a PCV other than stock?