Chevy Impala SS Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
1,486 Posts
Discussion Starter · #1 ·
This is obviously a non-issue for regular folks, but performance guys/engine experts please give me your feedback.

I was down at Atlanta Motorsports Park over the weekend, and the track has a VERY long, high speed slightly off camber sweeper, (see turn 13-15 in track map photo and 1:15 in the video) that I was taking flat in 3-4-5th gears. I noticed a bit of a burning oil smell after a few laps, but didn't think too much of it, UNTIL a lap or two later I noticed I had a bit of a smoke plume trailing the car around that same corner. I chalked it up to a little oil getting sucked into the intake, as my oil pressure was fine and engine performance seemed to be solid.
198811



After the session, I hopped out to find oil ALL OVER the RH side of the engine, from the top of the valve cover near the PCV grommet all the way down onto the headers and also the frame rail. I immediately assumed my catch can was overflowing and spilling out onto the area as it is immediately above, but when I unscrewed it, it was only about 3/4 full, with no evidence of leakage. Upon closer inspection, it did seem to be pooling up or sloshing around inside my valve cover enough to literally pour out of the PCV grommet area where I have my Deutsch plastic breather baffle/catch can hose attachment. See photos:
198813

198817
198818

198819

198814


RH catch can photo for setup/hose routing reference. LH catch can had barely anything in it, and most of it was from the 750 mile trip down to the track. In two full days on track, the LH can only collected about 1/4" of oil total.

Obviously the main issue is the oil not draining quickly enough out of the head and back into the block/pan, so that would be my long term goal. Tips for that??

Short term, I was thinking of either flipping the RH valve cover 180 degrees so the baffle filter/grommet are more forward and thus higher up/further away from the outside/rear of the head where I'd imagine the oil is pooling OR swapping RH cover with LH cover?

My two main goals are obviously keeping oil from leaking out of the valve cover (especially near hot exhaust) AND also keeping oil out of the intake charge and off the MAF and IAT sensors. The car ran strong and did not falter, despite the MAF and IAT being covered in oil all day, and obviously a ton of oil in the intake charge.

NOW, this is the first track I've ever driven that had a flat out 4th/5th gear looooong sweeper, and I wouldn't expect and have not experienced this problem at other tracks.... yet, but would like to try to alleviate it as best as possible.

Advice???

THANKS!
 

Attachments

·
Registered
Joined
·
2,109 Posts
… Atlanta Motorsports Park … track has a VERY long, high speed slightly off camber sweeper, (see turn 13-15 in track map photo) that I was taking flat in 3-4-5th gears. noticed a burning oil smell after a few laps, didn't think too much of it, lap or two later I noticed I had a bit of a smoke plume trailing the car around that same corner. chalked it up to a little oil getting sucked into the intake, oil pressure was fine and engine performance seemed solid. View attachment 198811
After the session, oil ALL OVER the RH side of the engine, from the top of the valve cover near the PCV grommet all the way down onto the headers and also the frame rail …
Upon closer inspection, it did seem to be pooling up or sloshing around inside my valve cover enough to literally pour out of the PCV grommet area where I have my Deutsch plastic breather baffle/catch can hose attachment.
View attachment 198813
View attachment 198817 View attachment 198818
View attachment 198819
View attachment 198814
RH catch can photo for setup/hose routing reference. LH catch can had barely anything in it, and most of it was from the 750 mile trip down to the track. In two full days on track, the LH can only collected about 1/4" of oil total.

Obviously the main issue is the oil not draining quickly enough out of the head and back into the block/pan, so that would be my long term goal. Tips for that??

Short term, I was thinking of either flipping the RH valve cover 180 degrees so the baffle filter/grommet are more forward and thus higher up/further away from the outside/rear of the head where I'd imagine the oil is pooling OR swapping RH cover with LH cover?

My two main goals are obviously keeping oil from leaking out of the valve cover (especially near hot exhaust) AND also keeping oil out of the intake charge and off the MAF and IAT sensors. The car ran strong and did not falter, despite the MAF and IAT being covered in oil all day, and obviously a ton of oil in the intake charge.

NOW, this is the first track I've ever driven that had a flat out 4th/5th gear looooong sweeper, and I wouldn't expect and have not experienced this problem at other tracks … yet, but would like to try to alleviate it as best as possible.
Only way to swap valvecovers is to turn them about face; they only screw onto the heads one way.
When the PCV & passive valvecovers swap places, the PCV grommet is on the front driverside.
Set aside the oil filler neck and screw the oil cap directly onto the PCV valvecover if you can't find an oil filler neck that resembles a silly straw.

I Used to use two PCV valvecovers with siamesed PCV routing to the throttle body.
Although I also used to drive like a cabbie on meth, I don't know if two PCV valvecovers will be of any help to you?

A better-sealing PCV grommet obviously does not fix the fundamental issue.
Though if you drive the track clockwise, you can leave the valvecovers be.

Fundamental issue:
either too much oil being thrown at the even cylinder head, or not enough oil draining from the even cylinder head.
Sounds like a job for a dry sump.
Don't know if using the PCV valvecover on the driverside will fix oil draining too slowly from even head.
Maybe if you could suck / pump the oil from the even cylinder head to the side cylinder head?
I mention this because I'm afraid your odd cylinder head might be starving for oil …

Also don't know if a customizable PCV valve will help?
For the life of me I know that SOMEONE here at the ISSF mentioned one of these things, but I cannot find the thread that mentions it …
 

·
Registered
Joined
·
7,249 Posts
Unclear why continue to route to throttle body. Certain to draw air up through oil drain holes at times. One set-up I believe to be effective are a hose from each cover leading to a catch can high up on firewall with remote breathers. Encouraging air moving down through drain holes. Thereby encouraging oil down to crankcase as well...
 

·
Registered
Joined
·
2,109 Posts
Unclear why continue to route to throttle body. Certain to draw air up through oil drain holes at times.
One set-up I believe to be effective are a hose from each cover leading to a catch can high up on firewall with remote breathers; encouraging air moving down through drain holes, thereby encouraging oil down to crankcase as well …
Seems like this requires another PCV valvecover on the driverside.
(However, these steps in and of themselves may not address the leaky grommet?)
Or maybe just use valvecovers so tall that the oil cannot reach the ceiling?

By the way:
Getting the correct PCV for your build.
 

·
Registered
Joined
·
7,249 Posts
Why wouldn't one want a breather on each cover? PCV in the intake practically begs for this set-up.
Hoses to throttle bodies just don't solve the problem(s). Or, myself along with everyone else would have them too.
Installing a filter to trap oil/vapors become restricted almost immediately, and are little more than a band-aid in my opinion.

198822
 

·
Registered
Joined
·
1,486 Posts
Discussion Starter · #6 ·
Unclear why continue to route to throttle body. Certain to draw air up through oil drain holes at times. One set-up I believe to be effective are a hose from each cover leading to a catch can high up on firewall with remote breathers. Encouraging air moving down through drain holes. Thereby encouraging oil down to crankcase as well...
So I'm definitely moving in that direction. I'm taking smaller steps as these issues pop up. Never seen any situation like this happen on track with my car before. Never ran a 1/4 mile long sweeper flat out in 3rd/4th/5th gear before.

The big catch can on the pass side does have a provision for a breather filter, and considering getting another "pass side" valve cover to do the same catch can setup for the driver side. At that point I can plug the outgoing inlet to the intake on both sides for track days too.

Do you think I'm seeing enough crankcase pressure to be pushing "upward" out of the drain holes in the heads to be preventing oil drain back? If so, then yes, I definitely see the valve cover breathers as being a huge advantage. If not, then I'm really just going to have a bit more of an oily mess, just higher up in the bay too. as I'd see some of this oil mist getting out through the filter.

Ideally, I like the idea of dual cans w/ breather filters that I can remove/plug for street duty, as I got literally NOTHING- zero oil or even residue/condensation in the pass side can over 1000 road miles, including a a few hours of WOT+ high rpm 2nd and 3rd gear usage on the Dragon/US 129/Deals Gap, and only about 1/2" of oily residue in the much much smaller driver side can hooked up to the PCV over that same period.
 

·
Registered
Joined
·
7,249 Posts
If road courses contain more problematic right hand turns than left? Then one could just swap covers ,and have passenger side totally sealed with a breather in front on driver's side...
 

·
Registered
Joined
·
1,486 Posts
Discussion Starter · #8 ·
I would say most tracks typically run clockwise, with most of the corners being right handers, but I'd like a solution that works at all tracks without having to swap covers back and forth etc. The thought did cross my mind at AMP this Sunday, but I wouldn't have had quite enough time between sessions to swap covers and everything.
 

·
Registered
Joined
·
2,109 Posts
For whatever it's worth, my guess is that turn 13-14-15 is long enough to centripetally force motor oil toward the even side.
IFF you were to get a dispensation to drive this course clockwise, turn 16-15-14-13 would centripetally force the motor oil toward the odd side; in which case the 13-12 transition would be exactly when you would NOT want a PCV valvecover on the engine's odd side because hard braking would force motor oil forward & out the grommet.
The big catch can on the pass side does have a provision for a breather filter, and considering getting another PCV valve cover to do the same catch can setup for the driver side. At that point I can plug the outgoing inlet to the intake on both sides for track days too.
You should definitely get a 2nd PCV valvecover and do a similar catch can setup on both sides.
On any racetrack, use both breathers.
Ideally, I like the idea of dual cans w/ breather filters that I can remove/plug for street duty, as I got literally NOTHING- zero oil or even residue/condensation in the pass side can over 1000 road miles, including a a few hours of WOT+ high rpm 2nd and 3rd gear usage on the Dragon/US 129/Deals Gap, and only about 1/2" of oily residue in the much much smaller driver side can hooked up to the PCV over that same period.
This is the way to go.
 
1 - 11 of 11 Posts
Top