So first, I've been investigating this for a while. Crankcase breather- or PCV filter- to keep "oil-contaminated air" from going into my intake "robbing" my car of hp. Seems plausible...
Anyone know? Its a cheap mod to throw a filter on, but is it really for good measure or just pointless?

Also, air intake. I'm still fighting with this. What diameter should it be? I've seen that a good rule of thumb is whatever the stock intake is- 2.5". I have a 3" Intake. Should I downsize?

Also, what do you find works best for keeping the pipe cool under the hood. Reflective tape? Paint?

 

... oil-contaminated air ... robbing your car of HP... That sure sounds like a sales pitch. Anyway, when the system is all working properly, it's like this:

- The PCV valve allows a little air to be sucked out of the crankcase into the intake manifold. The plunger inside the PCV valve is supposed to control the amount as you open & close the throttle.

- The crankcase breather tube draws air from the intake tube into the crankcase, to make up for what's sucked out by the PCV valve. So normally, the crankcase is simply an alternate path for air to get from the air filter to the intake manifold.

During wide-open-throttle operation, blowby around the piston rings likely is large enough to reverse the vent flow. So oily air flows backwards through the vent, into the rubber intake duct. That should only be occasionally, and doesn't hurt anything. If you get enough blowby for this to happen all the time, you should look at the reasons for that.

That large intake duct makes for a really REALLY poor heat-exchanger. There's very little residence time for the air flowing through there. As far as choosing the size, I think any resonance of induction pulses really happens in the runners from the IM plenum into the valves.

 

Ok. I was looking more on the crankcase vent and it looks more for FI engines, however, I could use a small in line fuel filter between the pcv and the IM to put any concerns to rest. I just remember replacing my intake manifold and seeing all that crap in there that im sure some of it was oil from the pcv.

I'm thinking something like this
http://www.ebay.com/itm/140772697539
In between the pcv and IM and then just a small filter on the other side of the valve cover. That work fine?

As for the intake duct, by poor heat exchanger you mean that i need not to worry about it or I do? Would I be better off with a 2.5" intake with heat wrap around it?

I was talking to TexasHonda and he said that my intake temps seemed a bit high. They actually got up to 90f in 35f weather in stop and go traffic. I'm looking for ways to reduce that temp.

 

Search for "catch-can". Seems to me you only need a can with a couple baffles, the oily air slows down enough to allow the oil to drop out. I think sometimes it's a can filled with steel wool or something like that?

Where's your intake coming from? Is it already aftermarket? Does it draw hot air from the engine compartment (short-ram)? Without doing a proper calculation, I expect the temperature comes from whatever location you're drawing the air from.

 

I was looking into catch cans. Could I replace the filter in a clear inline filter with steel wool? That wouldnt address the issue if the air from the crankcase is heating up the intake though....

You can see a photo of my engine bay in my pics. The intake is going under the wheel well like a typical f22 cai. I bought a digital thermometer to find out where exact the air heats up. The IAT sensor is in the f23 location which is on the farthest side of the upper manifold.

I had to splice and extend the wires to make it fit, could the sensor be off damaged or the wires not have a secure enough connection? Maybe the intake temp isnt as high as it says.

Reading back on your first response it would make sense that that is the problem if the air coming in is at ambient temp and its going through too fast too heat up. It must be the sensor right? or pcv air coming in and the sensor is picking that up.

Also as far as the intake design, I agree that whats more important is in the IM after the TB but I'm reading different views on the matter. I think of acoustics similar to exhaust happening in the intake pipe. Or is that just splitting hairs?