Oh No, I completely agree 100%.

I think speculating that this increases performance is complete

I think if there were a case where Oil was creating an ignition problem it would.. But thats not going to be the case 100% of the time.

My Fuel Economy got better, thats all I can say. Maybe yours will, maybe yours won't.

All I know is that just a bit ago I emptied yet another cup half full of Oil that was sent blow by.

Oh.. And no-one likes trying to clean an 00Vi.

 

While not having a direct effect, catching the oil in blow by gases can indirectly affect performance. Reducing the oil in the intake manifold effectively raises the octane rating of the fuel, making it more resistant to detonation. This can be beneficial with increased timing, high compression, or just on really hot days. Also, reduction of oil in the manifold means less carbon buildup in the combustion chamber, leading to a reduction in the tendency of an engine to knock. Less carbon buildup can prevent poor sealing valves or spark plug fouling (in extreme cases) as well. Furthermore, if your car has active knock monitoring (like the Maxima), then the ECU can keep the timing more optimized, and be less concerned with detonation. This means higher cylinder pressure and better efficiency/power.

The theory is sound, all the proof you need is slowly collecting in the little plastic bowl.

The only reason I can think of to not have a catch can is if you never want to empty it, which is probably the reason behind cars not having them from the factory. People are lazy.

 

I did this on my old Dodge Durango and it helped. Amazing how much oil it caught. I just used the regular water separator used for air compressors, think it cost me a total of under 10 bucks including new hose.

 

I find I need to empty mine every week. As more oil builds up inside, it becomes less effective. I gained 2 mpg after emptying it the last time. Before that, I had not emptied it in about four weeks.

Whats really disturbing is how little oil came out of my engine after 8000 miles on my last change. I always put in 4.5 quarts. I only recovered 2.5 quarts. Oil lost to blow by is insignificant during a 3000 mile OCI, but if you use something like Amsoil, and have extended OCIs, you should consider adding some clean oil depending on my much you catch.

 

thats what she said

my car just hit 160K and ive been doing some maintenance. this is on my list to do and im interested to see if it makes a difference for me

 

I just reconfigured the oil separator on my car. I was unhappy about having to empty the smallish bowl of the home depot/lowes separator so often so I was looking for a new solution. My bowl had also developed cracks and was no longer holding oil. I found this. It's a cyclonic separator from an M5. I hooked it up and used a HDPE bottle (same plastic all oil bottles are made of) with a fitting screwed in the top to collect the oil. It works great and should only need emptied monthly. The only problem is that when the HDPE heats up, the vaccuum on it causes it to compress. I think a aluminum bottle would have been better, but didn't have any sitting around. I mounted the collection bottle to the resonator below the battery. McMaster-Carr p/n 6810T53 looks like it would be perfect.

I JB welded two 3/8 hose barb x 3/8 MIP fittings into the two large ports on the separator. A 3/8 hose pushed onto the bottom port with some coaxing.

 

/\ Excellent. Thanks for the update. Have any installed pics?

 

Sorry, I lose track of the threads I post in sometimes. I do have pictures. I'll try to transfer them from my phone after class.






In the first picture, the PVC hose leaves the valve cover and passes under the throttle body and MAF. It enters the separator and exits. It follows the radiator, the A/C line and then the FSTB. I did it this way because that was the best place for the separator as far as I could tell. I was trying to make it look like it belongs there.