LFX getting lots of KR

[Bika]

Very early. like 1000 or 2000 miles. I took the can apart today and while it is catching alot of oil, much is still getting through to the intake manifold. The coalescing media was soaked in oil, the hose to the IM had oil residue in it, and the front of the IM under the hose fitting was coated with oil. The "Clean side" pcv was dry.

I wish I knew why i was sucking in so much more oil than most. Every few hundred miles I get a couple ounces of oil in the can, and that's just what is being caught. I Seafoamed it today and threw the RotoFab intake back on.

F this car.

[Bika]

Since one of the Elite catch cans and the clean side separator isn't doing enough, I was thinking of running two.

Anyone run two cans in-line on the dirty side?

I have to stop this oil. Ive driven about 500 miles since the valve cleaning and the intake manifold is already coated in oil.

[jtrosky]

Personally, I've never heard of anyone running 2 catch cans in-line. Let me ask you this - when was the RotoFab intake installed? I'm wondering if the RotoFab intake is somehow changing things enough to allow more oil to get to the intake valves. I know that you said re-installing the stock intake didn't correct the issues you were having, but it still possibile that the RotoFab is what caused the issue to begin with (and one the issue exists, it doesn't matter what intake you use).

Just throwing this out there. I honestly have no idea if it's even possible for a RotoFab intake to allow more oil to get to the intake valves or not (not directly, but indirectly).

Anohter possible option is to swith to a RX catch can - I head that they are supposed to be the best on the market - but again, I have no personal experience with them (don't run a catch can on my Impala with LFX and have no issues and no oil consumption at all).

[Bika]

The intake was installed last summer. Not quite on for a year. The elite catch can was the first thing i did at 700 miles. I heard good things about Elite. Don't know if it's the best but definitely not junk.
The dealership said they have seen many camaros with this pcv issue, but not really any other LFX cars.

I worry about too much crank case pressure building up if I add a 2nd can.

I guess I will be stocking up on seafoam and CRC top end cleaner...

[Bika]

I suppose it's possible the increased airflow from the rotofab might draw more oil through pcv.. Not sure how though.

[jtrosky]

Yeah, I really don't know either... I suppose that you could try running with stock intake for a while to see if the problem returns or not.

Does the RotoFab intake give you any signifcant performance increases? I don't know anything about them (still run stock intake on my Impala). But, as you eluded to - even though the Camaro and the Impala both have an LFX engine, they are tuned very differently and are very differernt beasts...

I've heard of Camaros having issues with "valve coking", but definitely not to the extreme that you've had on yours. For it to run so poorly until you had a top-end cleaning done, with so low mileage, just seems strange and abnormal to me....

[Bika]

I don't know what if anything the intake does for performance. Sounds really cool though. Honestly it feels like it wants to move better on the low end with the stock intake. I'm on a stock tune so it probably gains little to nothing.

[Area47]

Area, just curious, what is your reasoning for getting rid of the VMAX honed TB? Everyone swears by these things over on Camaro5 forums, although I can't see that it does a damn thing.
I'll msg you so maybe you can help me make this thing not such a turd. I didn't buy it for speed, but ugh...

Meh. This engine really makes me miss my old LSJ. Shoulda spent the cash to rebuild it. :-\

I have made more power with an intake and no mufflers on one that others have with all the bolt ons they could think of. Without proper tb tables, it's a moot point at best.

[jtrosky]

While I agree that the VMax ported TB doesn't really do much (if anything) - at least on my LFX Impala, I don't think it hurts anything, does it? I mean if I have the choice of a OEM TB with 5k miles on it (that was sent to VMax for porting) or my stock OEM TB with 50k miles on it (no porting), I'm assuming that I'll probably be better off with ported TB - mainly becuase it's much newer. While the porting doesn't seem to do much, I certainly don't think it hurts anything either...

It's really strange - I know other LFX Impala owners that say that the VMax ported TB make a significant difference for them. Same with other Camaro owners. Not sure if it's just the "power of positive thinking" that they feel or if some of the ported TB's work better than others? On my car, I have significantly altered the throttle feel via the Driver Demand table modifications, so maybe that's why I don't feel any difference - but since @bika is running a stock tune, you'd think that he would feel the difference... Just don't know.

[Area47]

if you manipulate the DD tables enough and torque commanded tables you won't see a difference in the ported tb, versus stock. My money is on the power of positive thinking.

[Bika]

Positive thinking. The throttle plate size isn't changed. Vmax is not really ported, just the inlet honed and smoothed. Might as well burn your money.

I'm not cutting off the stock mufflers as it sounds like a weed eater. I don't have a wide band on this one so I'm limited on what I can due with the tune. Any words of wisdom?

[Area47]

Positive thinking. The throttle plate size isn't changed. Vmax is not really ported, just the inlet honed and smoothed. Might as well burn your money.

I'm not cutting off the stock mufflers as it sounds like a weed eater. I don't have a wide band on this one so I'm limited on what I can due with the tune. Any words of wisdom?

factory wideband. it's a GDI car.

i did a 11 v6 car with headers no cats, no mufflers. I wanted to kill myself.

[jtrosky]

While the Impala and the Camaro are certainly different beasts even though they use the same engine, I've had great success by changing the following on my Impala tune (although I am tuning for comfort more than performance):

- Driver demand table changes. Interestingly, I made my Impala Driver Demand tables VERY similar to the Camaro Driver Demand tables (they are significantly different in stock form).
- Transmission shift tables and TCC lockup tables.
- DFCO tuning (I actually disbled it completely - hated the RPM fluctuations it caused for the minimal times it kicked in)
- PE tuning
- I did modify (reduce) some of my VCP spark values to reduce KR
- Tuned timing to come back twice as fast as stock when KR is detected
- Increased knock sensor thresholds for 0-2000rpm (I got a lot of false KR at 1200rpm and 1600pm - found my knock sensor thresholds were significanlty lower than the LFX Camaro for 0-2000rpm. Mine are still set lower than the Camaro though.
- Disabled tip-in limiting for all gears
- Disabled skip-shifts
- I lowered my SHift Inertia Factor Profile values in certain areas for all shifts
- SLightly reduced shift times
- Reduced upshift torque management levels for low/min RPM/torque shifts (by beteen 5% and 20%)

Those are the main changes I made. I *hated* the shifting in my 2012 Impala in stock forum (6T70 trans) - it's *so* much better with the changes listed above (but again, I was going for comfortable shifts, not "firm" shifts).

WOuld be glad to share my stock and custom tune files for comparison if you'd like... I'm far from an expert, but I have spent a LOT of time logging and tweaking to get where I'm at (with positive results). While you may not want to make the same changes, I think that just see what I did change to get my desired results can still be useful...

[jtrosky]

factory wideband. it's a GDI car.

Can you please elaborate? Are you saying that GDI cars have a facotry wideband?? That is defintiely news to me!!

[Bika]

factory wideband. it's a GDI car.

i did a 11 v6 car with headers no cats, no mufflers. I wanted to kill myself.

Bahahaha :lol:

I looked at the stock tune file briefly and didn't see any lambda tables. Maybe I missed it. I doubt there would be a different o2 from the 10-11 LLT to the 12+ LFX. Unfortunately everything is going to DI now. I remember the turbalts had the factory wideband. that was nice

I'll send you some logs when I get time to mess with it some more. Barely have time to take a shit anymore.

[Area47]

the 12+ is a different animal on the ecm side of things. The 10-11 mimics the lnf setups. The 12+ was beta for the new gen 5 lt engines.

[jtrosky]

Ok, so the LFX does NOT have a factory wideband then, correct? I was wondering how I missed that one!! :-)

But the Camaro LLT cars (pre-2012) *do* have a factory wideband? I never realized that either...

Or does it all depend on the exact ECM - not just the motor?

[Bika]

the 12+ is a different animal on the ecm side of things. The 10-11 mimics the lnf setups. The 12+ was beta for the new gen 5 lt engines.

Aw Balls. The LNF ecm I could understand. One look at the tune file on my car had me confused.

Now I'm hearing that the timing chains on the LFX tend to stretch prematurely.

I feel a trade in happening in the not too distant future. I am still kicking myself for being cheap and not getting the LS3 or L99.

[jtrosky]

I always heard that the timing chain stretch issues were for the LLT, not the LFX. Supposedly, if you cahnge your oil frequently enough (about every 5k miles or so), there are no issues with the timing chain on the LFX. At least that was my understnading.

[Area47]

Aw Balls. The LNF ecm I could understand. One look at the tune file on my car had me confused.

Now I'm hearing that the timing chains on the LFX tend to stretch prematurely.

I feel a trade in happening in the not too distant future. I am still kicking myself for being cheap and not getting the LS3 or L99.

shoot me a pm with your email. i'll get your feet wet with the lfx in a big hurry.