pcv valve

[chevyart]

im going to use a pcv valve setup on my 408 sbc. is there a real good one for hi-po engines, or are they all the same. thanks for advice art

[TopspeedLowet]

Race engines do not use PCV valves. Oily air drawn in the intake from the crankcase in a racing engine is a bad thing and does not provide any crankcase vent at WOT when you need it the most for ring seal etc. Use a header evac vent or two large breathers, one on each valve cover would be better than a PCV in a racing engine.
If you are a street engine application then use a PCV with the highest spring pressure and smallest hole or restrict the hose inner diameter to prevent drawing in too much air volume, use a large breather on the opposite valve cover for street applications.
Bruce

[chevyart]

thanksa bruce. it is a street engine and i will need to use the pcv setup. any idea how i could locate the pcv you described (heaviest spring and smallest hole).any certian cars that you know of would call for a pcv like this one. just out of curiosity, why the heaviest spring and smallest hole? thanks art

[TheRabbit]

At least you didn't say PVC valve. lol

[chevyart]

hey rabbit i always make myself say pos crank vent before i write the initials pcv, or else a will write pvc, which i used to do all the time art

[Scooterz]

hey rabbit i always make myself say pos crank vent before i write the initials pcv, or else a will write pvc, which i used to do all the time art


So true!!!!!! It's like I was a plumber in my past life or something... comes out of my mouth pvc every time no matter what.

[TheRabbit]

hey rabbit i always make myself say pos crank vent before i write the initials pcv, or else a will write pvc, which i used to do all the time art


So true!!!!!! It's like I was a plumber in my past life or something... comes out of my mouth pvc every time no matter what.

We've all done it quit a few times I'm sure. No matter how many times I hear it I still laugh.

[TheYellaBrick]

Positively Ventilated Crankcase

[nooblet327]

If you got long tube headers and good flowing exhaust setup use a crankcase evacuation kit or turn a smog pump into a crankcase vacuum or just stick some breathers on your valve covers. Contaminating your intake charge with hot blow by is just disgusting. And creating a vacuum in your crankcase lets them rings seal better lowering blow by and reduces the air resistance that the oil slinging off the crank loves to grab ahold of.