Please peruse my latest thoughts on trapping oil that normally travels past the PCV valve and into the intake manifold. You can find the article here:

http://www.conceptualpolymer.com/corvette_c5_corner.htm

It is entitled:

PCV Line Oil Removal 101

Thanks!

Dave

 

I installed a very nice billet catch can I bought from MTI on my vette when I put the present engine in. Until the rings seated it blew quite a bit of oil past the rings and out into the can - it would fill up about every 500 miles -- blowby was so bad when the engine was first in the car that crankcase pressure would push the dipstick out (we have to duct tape it in). But now, at 5,000 miles, the rings seem to have seated nincely and I get only a couple of thimble fulls every oil change (I cna the oil every 2000 miles).

 

Lee,

After 30 miles of hard mountain driving and 200 of normal driving, I found about 1/3 oz in the can. I should be able to go almost one year before having to empty again, but I'll probably do it every 6 months.

Dave

 

I have to admit...I've never heard of people doing this....I'll plead ignorance! I still have to read the entire post on your site Dave....to figure out exactly why and what the benefit of catching this oil. Is this a common thing for people to do? To any vehicle? or just high performance engines?

 

Kevin,

From what I've seen, it's primarily high-performance engines. Even the Neon SRT-4 and Cooper owners are using them.

Dave

 

Thanks for the response Dave.....ok...I read through your posting the other day. I understand, basically what's going on I think! So in a "nutshell" why is doing something like this advantageous? Keeping the engine cleaner? Longevity? Performance???? If it is better for the engine, why doesn't the factory do this to begin with? and why not on every car? Would it be good to do on my Tahoe, or just for the Vette? Thanks for your insight!

 

Kevin,

What typically happens is that the oil aerosols that flow past the PCV valve, coat your intake manifold. Over time, this oil is drawn into the combustion chamber, allowing carbon to form on your piston tops. Eventually, pinging is common-place because as the carbon builds on itself, the volume above the piston decreases. Since the piston travel stays the same, compression increases and that 91 or 92 octane gas we buy is no longer adequate to prevent pinging and the resulting retardation of timing by the ECU.
many C5 owners use Sea Foam occasionally to blast out the carbon, but this can a scary process for the DYIer. The dealership has an injector and TB cleaning service which does help, but I was a bit disturbed to find out that my car needed the service at 20,000 miles!
This is why I started researching catch cans. By the way, I can have some aluminum extension cans made by a machine shop for $30. I can also buy the coalescing filters for $43, so if you want a set, please let me know and I will get some. The $30 price applies only if I buy five at a time, so I am asking anyone who may be interested to let me know. I figure that with the extended can, the Watts filter set won't need to be emptied for about 5000 miles.
This brings up the possible reason for GM's not equipping its vehicles with catch cans. Must customers want to drive for 100,000 miles without having to change anything. Even your oil can go 10,000 miles under the right conditions. So, yes, the Tahoe would benefit, although it may not produce as much oil in the can, since the C5 is typically driven harder.
Hopefully, I will change the location of my filter to the front of the engine bay, soon and will post pics in my website.

Dave