The oil pan dictates whether you need a thick or thin gasket - the timing covers are all the same at the lower seal area. I have to admit though, it is darn near impossible to use the wrong gasket. If you have managed to put a thin gasket where a thick one is needed, then you'll be having more than a minor oil leak and you'll be able to see inside the pan. And if you've put in a thick one where a thin one is required, then you've warped the poop out of your oil pan along the rails. Personally, I've had very good luck with 4 piece cork gaskets, both FelPro and Mr. Gasket and haven't had much luck at all with the one piece rubberized ones. But I'm also anal retentive about installing them and tightening the oil pan bolts.
Regarding the PCV system - you definitly need one. The reason for having your crankcase ventilation system working off from both valve covers is to eliminate any condensation build from the non vented side. If nothing is venting from one side, then expect to see a milky residue on the non-vented side when the cover is removed. And you really don't want too much of that to accumulate in your crankcase.
In a nutshell, your PCV valve needs to be hooked into the intake somewhere below the throttle plate and the breather side should be attached somewhere above the throttle plates. An open breather will work, but not as well as a hose hooked above the throttle plates because the hose generates vacuum during hard acceleration whereas the open breather is only venting when the pressure is higher than atmospheric pressure.
Forgot to mention, what is needed for crankcase ventilation for a street driven car vs. a race car are not the same.
Regarding the PCV system - you definitly need one. The reason for having your crankcase ventilation system working off from both valve covers is to eliminate any condensation build from the non vented side. If nothing is venting from one side, then expect to see a milky residue on the non-vented side when the cover is removed. And you really don't want too much of that to accumulate in your crankcase.
In a nutshell, your PCV valve needs to be hooked into the intake somewhere below the throttle plate and the breather side should be attached somewhere above the throttle plates. An open breather will work, but not as well as a hose hooked above the throttle plates because the hose generates vacuum during hard acceleration whereas the open breather is only venting when the pressure is higher than atmospheric pressure.
Forgot to mention, what is needed for crankcase ventilation for a street driven car vs. a race car are not the same.
