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LFX, LF3, and what ever (designation or variant) mods for the High Feature GM V6 by Rickady88GT
Started on: 12-04-2018 10:37 PM
Replies: 20 (294 views)
Last post by: Rickady88GT on 12-08-2018 10:20 PM
Rickady88GT
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Report this Post12-04-2018 10:37 PM Click Here to See the Profile for Rickady88GTClick Here to Email Rickady88GTSend a Private Message to Rickady88GTEdit/Delete MessageReply w/QuoteDirect Link to This Post

Because of all of my interest in the cool engine, I searched for modifications for it. I can't believe how little I found? This engine has been around for years and in in many platforms, but articles and build videos are eluding me.
Asking for help with actual modifications not just cold air intakes and exhaust mufflers. Please post them if you know of them.

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mender
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Report this Post12-05-2018 02:16 AM Click Here to See the Profile for menderSend a Private Message to menderEdit/Delete MessageReply w/QuoteDirect Link to This Post

I basically ported the air path through the engine, starting with filling and porting the intake manifold. CAI, can't do headers but will have a decent exhaust system.

It's already turned up pretty good so about the only thing left to do would be cams. No magic tweak that I was able to find including whether the RWD intake was better than the FWD intake. HP ratings seem to indicate that might be the case. Would have to test an Impala intake against a Camaro one on a dyno to find out.

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Joseph Upson
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Report this Post12-05-2018 07:33 AM Click Here to See the Profile for Joseph UpsonClick Here to Email Joseph UpsonSend a Private Message to Joseph UpsonEdit/Delete MessageReply w/QuoteDirect Link to This Post

The info is limited because the majority of the performance modifications take place in the original platform and have to conform to parameters in which the system will operate trouble free, which is limiting within itself as sometimes the window of deviation is very narrow. The greatest source of info can be found on the Camaro forums where much of the experimentation is discussed out in the open, at least initially until someone thinks they have something that might be profitable it appears, then suddenly the flow of info stops. There are a lot of really good threads that suddenly drop off at the most crucial point, the conclusion.

In all the reading I've completed to date on the subject, I understand you would be wise to be very careful in your approach to porting the heads. A lot of work has gone into the direct injection and intake airflow process which appears to have made idle conditions very sensitive to subtle changes in some cars. Something as simple as turning the fuel injector plugs facing the wrong way can result in lean idle codes and misfires at idle. There is a TSB that addresses it.

The safest camshaft is the stock camshaft, or a camshaft that is exactly like stock except for maybe a little more duration and lift, perhaps a regrind on the same centerline. I have read where one aftermarket vendor who provided "performance" camshafts as one of a number of upgrades on one of the Camaro forums, became a forbidden name for several reasons, one of which involved the inability to tune the camshaft upgrades satisfactorily and a lot of complaints and lost time and money among customers.

The motor got its start in the CTS, and eventually the Camaro was added and those two have the motors with the highest output. Some of the differences in performance across vehicles is probably attributed to the exhaust system and programming as well as part differences, for example, the LLT motor had an exhaust cam change before the advent of the LFX, so the VIN# is very important now in identifying what you have as the motors may look the same on the outside and have different parts on the inside.

Although not thought of much because of the allure of the highest performance ratings available, the most practical 3.6L for a swap is the first design LY7 for the following reasons; It has been around the longest and is most accommodating of modifications being port injected, which also lends itself to fuel injector upgrades at costs comparable to current pushrod motors, it has a 270 hp version available beginning in 07 (Saturn Outlook, Buick Enclave) at 10.2:1 compression so bumping that compression to that of the LFX along with the addition of the LFX cams alone should bring it fairly close to LFX performance level, not to mention the port injection would better tolerate any additional modifications, like porting, and headers. It is also the most experimented with to date.

Tune ability is will likely be the greatest challenge, auto manufacturers are making the systems more complicated and increasingly difficult to manipulate. I foresee a time possibly right around the "corner" where necessary system updates will be regular process rather than corrective and will come with a fee outside of warranty, like computer program updates. The ground work has already been set in place with Global A architecture and a requirement of a subscription to the GM link that contains the VIN data for programming new modules/computers starting around 2010.

If you're using an automatic, the BCM may be required depending on the year and all of it will need to be VIN matched so keep that in mind before pulling parts from different vehicles as it is not always as simple as changing the VIN as I've read a number of instances where that was done successfully and the part (Camaro trans in this case) still would not work.

The best advice is to keep it as simple as possible.


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Raydar
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Report this Post12-05-2018 07:51 AM Click Here to See the Profile for RaydarClick Here to Email RaydarSend a Private Message to RaydarEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Joseph Upson:

Although not thought of much because of the allure of the highest performance ratings available, the most practical 3.6L for a swap is the first design LY7 for the following reasons; It has been around the longest and is most accommodating of modifications being port injected, which also lends itself to fuel injector upgrades at costs comparable to current pushrod motors, it has a 270 hp version available beginning in 07 (Saturn Outlook, Buick Enclave) at 10.2:1 compression so bumping that compression to that of the LFX along with the addition of the LFX cams alone should bring it fairly close to LFX performance level, not to mention the port injection would better tolerate any additional modifications, like porting, and headers. It is also the most experimented with to date.



I was under the impression that the DI system was what allowed the bump in compression. (I've never owned or tweaked an HF V6, so it's obviously not the voice of experience speaking.)

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Report this Post12-05-2018 10:14 AM Click Here to See the Profile for Joseph UpsonClick Here to Email Joseph UpsonSend a Private Message to Joseph UpsonEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Raydar:
I was under the impression that the DI system was what allowed the bump in compression. (I've never owned or tweaked an HF V6, so it's obviously not the voice of experience speaking.)


Both engines are rated for 87 octane, the DI motor runs better on premium apparently due to programming which can sense premium fuel use some how, so not at all. The LY7 can handle as much compression as the pump fuel will allow and with the reserve GM often designs into the system the LY7 can probably with stand a bump to the same compression ratio as the DI motor and still run regular fuel. The direct injection definitely helps, but don't forget about the combustion science incorporated into the design to help pave the way.

In my own accomplishments experimenting with lesser motors, it seems all of the GM production motors are capable of a lot more than what is delivered. It's just easier to keep a leg up on EPA and other government expectations by rationing out progress a little at a time over years (like 11.5:1 compression on an engine that can probably do 14:1 on premium) instead of all at once and then shortly afterward, being pressured to do better than your research has been proven possible in a shorter time than you're prepared for.

The turbocharged LF4 3.6L has a compression ratio of 10.2:1 and reaches 18 psi of boost and owners are pushing it further on pump gas. How many Fiero members would have alleged you are a quack for attempting such a combination just 6 short years ago.

Direct injection is just the foundation for hashing out more of what GM and others already knows is possible ahead. I can't wait to see who will be the first to produce a domestic turbocharged car with 11:1, or more compression ratio.

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mender
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Report this Post12-05-2018 11:22 AM Click Here to See the Profile for menderSend a Private Message to menderEdit/Delete MessageReply w/QuoteDirect Link to This Post

Direct injection does three things:
1. Increases the amount of air/oxygen entering the engine by injecting the fuel into the combustion chamber. This eliminates the need for the incoming air charge to carry in the needed fuel.

The atomized and partially vapourized fuel from a port injected engine displaces some of the air, generally considered to be about 10% of the total volume. The additional air volume that results from not carrying in the fuel during the intake stroke is only available to a DI engine.

2. Controls the pressure profile during the combustion cycle via the timing and volume of the injected fuel in the same manner as modern diesel engines. The central location of the injector plus the interacting shape of the combustion chamber and the top of the piston create the desired turbulence to allow this controlled burn.

A port injected engine delivers the desired amount of fuel before the intake valve closes and therefore has no further control over the combustion process.

3. The DI greatly reduces detonation by controlling and centralizing the flame front, again in the manner that diesels do. The fuel being injected is directed at and ignited by the spark plug but from that point, the flame front is essentially the region of interaction between the air charge and the spreading fuel. There are no stray pockets of unburned air-fuel mixture to worry about as the pressure and temperature in the chamber rises and surpasses the auto-ignition point of a typical air-fuel mixture.

A port injected engine depends on a controlled burn to reach those pockets of air-fuel mixture before the temp and pressure in the cylinder reaches the auto-ignition point. If not, destructive detonation occurs as those pockets spontaneously combust, producing the spikes in pressure that is heard as pinging or knocking. Higher compression obviously contributes to the rise in pressure and temp and the octane level of the fuel is crucial in preventing detonation by raising the auto-ignition point. For a given quality of fuel, a port injected engine will be compression limited as compared to a DI engine.

For those reasons, a port injected engine will always make less power and be more octane sensitive than a DI engine. In turbocharged applications, DI allows compression ratio and boost numbers that would be destructive in a port fuel injected engine and represents a significant step forward in engine design and capability.

[This message has been edited by mender (edited 12-05-2018).]

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Report this Post12-05-2018 12:27 PM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreEdit/Delete MessageReply w/QuoteDirect Link to This Post

GM and others rated many engines and whole drive trains w/ Low HP and Torque in publish Sales and other doc's on purpose. So don't go by them.
Not only for EPA but Sales data matters to get Lower Insurance for the owners etc. Sometimes GM et al simple lies to make other engines look better in sales doc's.
And That's ignoring "gas hog tax" from many Govrmnts now in the books or from EPA dinging the CAFE points to car makers that can cost Millions to them. Near future the EPA and NHTSA are trying to amend CAFE (Corporate Average Fuel Economy that apples to even vehicle a manufacturer makes.) to "Safer Affordable Fuel Efficient" (SAFE) for 2021+ models. See https://www.epa.gov/regulat...fe-vehicles-proposed

In fact Many GM and others cars had "Lean Burn" code in PROM/MEMCAL in the ECM like Fiero to help MPG on the highway but Turned Off because won't pass EPA and some state's Emission testing. So say your Fiero makes 27 MPG on the highway but w/ "Lean Burn" can add 1 − 5 MPG on same road. (Engine w/ problems, like V6 etc w/ over high exhaust temps, then Lean Burn can fry the cat etc more easily too maybe part of why turn off but most is EPA problems.)

Yes, GM and many others designed and tunes most engines w/ max power/torque on 87 Octane in the US, ~91 RON in some other regions like most of Europe. Back then (until ~ late 90's) was about 5 − 10¢ price between grades in the US but wider diff in Europe and others mainly because of taxes there. Now in US the diff between grades is 25 − 50¢ per step of grade. IOW Current 87 is 2.139 right now here... mid is ~ $2.50 and high is close to $3.
Many People won't buy a car that requires more then 87 octane to run right because of high pump price.
Many cars run on 87 but engine is design to run 91 or more and owner book says use 91+ and get poor MPG and Power using 87 because has Knock sensors etc knocking back engine timing, boost pressure, and so on. My neighbor was shock that to find owners manual said use 91 because higher pump price even tho he get a little better MPG. (He bought car used and didn't read that data before buying.)

These two are why most engine in a given class is close to same numbers. Many only get a minor bump in HP/torque w/ turbo or supper changing as well. Even w/ higher octane at the pump the small amount of octane only make a little better because can't use high boost pressure.

So You can tweak timing on HEI or otherwise make higher performance using 91+ octane w/ hacked ECM/PCM mapping but even w/ a knock sensor you can/will have problems if you can't spend money for high octane gas in the future. Selling a car that needs high octane gas can be hard too.

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[This message has been edited by theogre (edited 12-05-2018).]

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Report this Post12-05-2018 02:01 PM Click Here to See the Profile for Joseph UpsonClick Here to Email Joseph UpsonSend a Private Message to Joseph UpsonEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by mender:

Direct injection does three things:
1. Increases the amount of air/oxygen entering the engine by injecting the fuel into the combustion chamber. This eliminates the need for the incoming air charge to carry in the needed fuel.

The atomized and partially vapourized fuel from a port injected engine displaces some of the air, generally considered to be about 10% of the total volume. The additional air volume that results from not carrying in the fuel during the intake stroke is only available to a DI engine.

2. Controls the pressure profile during the combustion cycle via the timing and volume of the injected fuel in the same manner as modern diesel engines. The central location of the injector plus the interacting shape of the combustion chamber and the top of the piston create the desired turbulence to allow this controlled burn.

A port injected engine delivers the desired amount of fuel before the intake valve closes and therefore has no further control over the combustion process.

3. The DI greatly reduces detonation by controlling and centralizing the flame front, again in the manner that diesels do. The fuel being injected is directed at and ignited by the spark plug but from that point, the flame front is essentially the region of interaction between the air charge and the spreading fuel. There are no stray pockets of unburned air-fuel mixture to worry about as the pressure and temperature in the chamber rises and surpasses the auto-ignition point of a typical air-fuel mixture.

A port injected engine depends on a controlled burn to reach those pockets of air-fuel mixture before the temp and pressure in the cylinder reaches the auto-ignition point. If not, destructive detonation occurs as those pockets spontaneously combust, producing the spikes in pressure that is heard as pinging or knocking. Higher compression obviously contributes to the rise in pressure and temp and the octane level of the fuel is crucial in preventing detonation by raising the auto-ignition point. For a given quality of fuel, a port injected engine will be compression limited as compared to a DI engine.

For those reasons, a port injected engine will always make less power and be more octane sensitive than a DI engine. In turbocharged applications, DI allows compression ratio and boost numbers that would be destructive in a port fuel injected engine and represents a significant step forward in engine design and capability.



I am aware of all of that, and much of it applies to both motors, just one more so than the other. I never said the LY7 could be made equivalent to the DI motors, I'm saying there's a lot more to be had from it on pump gas in its current state to bring it much closer than it currently is and I suggested above that the benefits of the Direct Injected version are probably not fully exploited. It goes without saying that the DI motor can accomplish more with a given octane, hence my statement; "The LY7 can handle as much compression as the pump fuel will allow". That's not to be read independently of its design limits. With an 87 octane rating, there's up to 93 octane performance improvement potential. The LY7 is still more flexible for performance enhancements due to its relative simplicity to the DI motor.

 
quote
Originally posted by theogre:
So You can tweak timing on HEI or otherwise make higher performance using 91+ octane w/ hacked ECM/PCM mapping but even w/ a knock sensor you can/will have problems if you can't spend money for high octane gas in the future. Selling a car that needs high octane gas can be hard too.


We're talking highly modified and customized old sports cars so those attributes are already assumed, present and accepted.

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mender
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Report this Post12-05-2018 02:45 PM Click Here to See the Profile for menderSend a Private Message to menderEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Joseph Upson:


I am aware of all of that, and much of it applies to both motors, just one more so than the other..

Actually, the list I made was about the differences between the engines so that other people would know more.

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Report this Post12-06-2018 04:06 AM Click Here to See the Profile for Joseph UpsonClick Here to Email Joseph UpsonSend a Private Message to Joseph UpsonEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by mender:
Actually, the list I made was about the differences between the engines so that other people would know more.


Fair enough. Don't waste your time with the intakes, the greatest benefit was likely switching to plastic over aluminum for the weight savings. The Camaro owners fabricated and fit an LLT intake in place of the plastic intake and though the results were higher hp using the original plastic intake, the owner interpreted the dyno results to suggest the overall difference favored the LLT intake because of its performance down low. The net results were not interpreted in a manner that suggested others should go through the trouble because it was too close to swapping apples for apples.

[This message has been edited by Joseph Upson (edited 12-06-2018).]

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mender
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Report this Post12-06-2018 10:56 AM Click Here to See the Profile for menderSend a Private Message to menderEdit/Delete MessageReply w/QuoteDirect Link to This Post

Any links to the intake comparison?

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Rickady88GT
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Report this Post12-06-2018 12:00 PM Click Here to See the Profile for Rickady88GTClick Here to Email Rickady88GTSend a Private Message to Rickady88GTEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by mender:

Any links to the intake comparison?


Or comparing the flow numbers of the different heads styles? Single exhaust and 3 ports.

And sleeving the block.

Does anyone have links to porting the heads?

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Joseph Upson
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Report this Post12-06-2018 12:06 PM Click Here to See the Profile for Joseph UpsonClick Here to Email Joseph UpsonSend a Private Message to Joseph UpsonEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by mender:

Any links to the intake comparison?


I'll have to search for it. I failed to backup my favorite links upon getting the urge and the unthinkable Google Chrome crash occurred erasing all of my links. The most recent backup I had dated back to June 2017. I lost about 200 plus links. The links could have been recovered had I remembered to access the backup file saved on the hard drive before reopening the browser. The favorites are saved every time the browser is opened. Since I opened it first and there was nothing to save, it recorded an empty file of the existing info that had been saved.

Here are a few I recovered that might offer something of value:

https://www.moderncamaro.co...h-feature-v6-11.html

https://www.moderncamaro.co...gine-conversion.html

https://www.camaro5.com/for...php?t=385386&page=41

[This message has been edited by Joseph Upson (edited 12-06-2018).]

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Report this Post12-06-2018 07:00 PM Click Here to See the Profile for MarkSClick Here to Email MarkSSend a Private Message to MarkSEdit/Delete MessageReply w/QuoteDirect Link to This Post

My LY7 in the Buick has about 190K on it now. I've replaced the water pump and fixed a minor leak in the timing cover so far (the trans was being rebuilt so that's when I did it, engine out lasted the trans). I would do a swap into my 86 with one of these if it were as straight forward as a 3800. No question. Used Quaker SUV synthetic / conventional since it was new according to the programmed oil change monitor, not at a 3K interval. Never goes a quart down between. Why is this engine so different from what I read here regarding oil / oil changes?

BR's,

Mark

------------------
86 SE V6 Auto
65 Tempest 400 CID
2018 Chevy Colorado Z71 3.6
2015 BMW 535iX M Sport
2008 G6 GT "Street" Coupe
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Report this Post12-07-2018 10:29 AM Click Here to See the Profile for Joseph UpsonClick Here to Email Joseph UpsonSend a Private Message to Joseph UpsonEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by MarkS:

My LY7 in the Buick has about 190K on it now. I've replaced the water pump and fixed a minor leak in the timing cover so far (the trans was being rebuilt so that's when I did it, engine out lasted the trans). I would do a swap into my 86 with one of these if it were as straight forward as a 3800. No question. Used Quaker SUV synthetic / conventional since it was new according to the programmed oil change monitor, not at a 3K interval. Never goes a quart down between. Why is this engine so different from what I read here regarding oil / oil changes?

BR's,

Mark



I suspect it has a lot to do with programming, application and production variations, for example, why is the recommended oil grade synthetic for the CTS and conventional for almost all others, higher load stresses, higher engine oil temps? Who knows. There's also a significant performance difference between the Buick LY7 and the CTS LY7 of the same year, 20 lb-ft is a lot and perhaps that along with other application specific differences weighed in. The CTS was at the top of the list with timing chain complaints in my understanding, and as mentioned elsewhere, extended oil change intervals (as much as 12k miles in the CTS) along with the occasional oil burner, set owners up for failure, because many assumed the oil life monitor surveyed oil quality and oil level and they neglected to check the oil level while waiting to be told to change it by the monitor, until there was a problem and by that time it was two late.

GM switched to a completely silent chain system over the previously mixed silent and roller assembly in 08. There was also apparently a bad batch of chains (like the bad batch of connecting rods in the first yr Fiero) which supposedly perpetuated the problem initially after the change. The LLT 3.6L was a big jump in performance and efficiency over the LY7 and the LFX is an improvement over the LLT. In 08 and beyond, all three used the same timing chain arrangement.

[This message has been edited by Joseph Upson (edited 12-07-2018).]

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Rickady88GT
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Report this Post12-07-2018 06:14 PM Click Here to See the Profile for Rickady88GTClick Here to Email Rickady88GTSend a Private Message to Rickady88GTEdit/Delete MessageReply w/QuoteDirect Link to This Post

Ok, been going through some of the links real fast. Not reading every word, but trying to glean some good info. Clearly the crank case vent issue is not resolved. If the engine does not get baked oil under the valve covers from whatever reason, the oil vapor is pumped into the intake manifold and builds up on top of the valves (some cases have very low miles on them and have noticeable build up bad enough to look like 100k worth). Even catch cans have not solved this issue in all cases. So my question is why not divert the crank case vapor away from the intake? Smog regulation aside, just avoiding oil build up inside the engine. What harm is there in plumbing the crank case vapor into the exhaust system after the o2 sensors?

[This message has been edited by Rickady88GT (edited 12-07-2018).]

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Report this Post12-07-2018 07:53 PM Click Here to See the Profile for Joseph UpsonClick Here to Email Joseph UpsonSend a Private Message to Joseph UpsonEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Rickady88GT:
Ok, been going through some of the links real fast. Not reading every word, but trying to glean some good info. Clearly the crank case vent issue is not resolved. If the engine does not get baked oil under the valve covers from whatever reason, the oil vapor is pumped into the intake manifold and builds up on top of the valves (some cases have very low miles on them and have noticeable build up bad enough to look like 100k worth). Even catch cans have not solved this issue in all cases. So my question is why not divert the crank case vapor away from the intake? Smog regulation aside, just avoiding oil build up inside the engine. What harm is there in plumbing the crank case vapor into the exhaust system after the o2 sensors?


It depends on the individual commenting and whether or not their catch can is of the proper baffling quality, as well as setup correctly. I've heard more success stories than failures once added. It's important to realize that this is standard PCV function, the difference being no fuel sprayed on top of the valves to help keep them fairly clean. A catch can capable of double duty, or two separate cans must be used because the bulk of the oil appears to be coming from the driver side, which has a larger diameter orifice end to end and can flow more volume. As the throttle opens and the crank case pressures start to build, the gasses take the path of least resistance and that's backward through the fresh air driver side and into the intake tube coming from the air filter. The oil catch can works when everything is correct. Some engine arrangements are worse than others, to the point of oil puddling inside the intake tube, to provide a good indication of how much can travel through that path.

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Report this Post12-07-2018 08:27 PM Click Here to See the Profile for MarkSClick Here to Email MarkSSend a Private Message to MarkSEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Joseph Upson:


I suspect it has a lot to do with programming, application and production variations, for example, why is the recommended oil grade synthetic for the CTS and conventional for almost all others, higher load stresses, higher engine oil temps? Who knows. There's also a significant performance difference between the Buick LY7 and the CTS LY7 of the same year, 20 lb-ft is a lot and perhaps that along with other application specific differences weighed in. The CTS was at the top of the list with timing chain complaints in my understanding, and as mentioned elsewhere, extended oil change intervals (as much as 12k miles in the CTS) along with the occasional oil burner, set owners up for failure, because many assumed the oil life monitor surveyed oil quality and oil level and they neglected to check the oil level while waiting to be told to change it by the monitor, until there was a problem and by that time it was two late.

GM switched to a completely silent chain system over the previously mixed silent and roller assembly in 08. There was also apparently a bad batch of chains (like the bad batch of connecting rods in the first yr Fiero) which supposedly perpetuated the problem initially after the change. The LLT 3.6L was a big jump in performance and efficiency over the LY7 and the LFX is an improvement over the LLT. In 08 and beyond, all three used the same timing chain arrangement.



If what I've read is anywhere near correct, the Buick Lacrosse / Rendezvous version does not have cam phasing on the exhaust cams. Only the intake. Might explain the performance difference. There is one not too far from where I live with 66k on it. Might go take a look!

BR's,

Mark

------------------
86 SE V6 Auto
65 Tempest 400 CID
2018 Chevy Colorado Z71 3.6
2015 BMW 535iX M Sport
2008 G6 GT "Street" Coupe
2005 Buick 3.6 Rendezvous

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Rickady88GT
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Report this Post12-07-2018 08:32 PM Click Here to See the Profile for Rickady88GTClick Here to Email Rickady88GTSend a Private Message to Rickady88GTEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Joseph Upson:


It depends on the individual commenting and whether or not their catch can is of the proper baffling quality, as well as setup correctly. I've heard more success stories than failures once added. It's important to realize that this is standard PCV function, the difference being no fuel sprayed on top of the valves to help keep them fairly clean. A catch can capable of double duty, or two separate cans must be used because the bulk of the oil appears to be coming from the driver side, which has a larger diameter orifice end to end and can flow more volume. As the throttle opens and the crank case pressures start to build, the gasses take the path of least resistance and that's backward through the fresh air driver side and into the intake tube coming from the air filter. The oil catch can works when everything is correct. Some engine arrangements are worse than others, to the point of oil puddling inside the intake tube, to provide a good indication of how much can travel through that path.

I agree, but I also think that the owner of the car should not have to buy aftermarket stuff to prevent the burnt oil buildup whether it is in the intake, valves or valve covers. This is clearly an issue related to Direct Injection and poor crank case ventilation.
But basically my question is, can the vapors be redirected away from the intake system and improve ventilation?

[This message has been edited by Rickady88GT (edited 12-07-2018).]

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Joseph Upson
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Report this Post12-08-2018 06:18 AM Click Here to See the Profile for Joseph UpsonClick Here to Email Joseph UpsonSend a Private Message to Joseph UpsonEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by MarkS:
If what I've read is anywhere near correct, the Buick Lacrosse / Rendezvous version does not have cam phasing on the exhaust cams. Only the intake. Might explain the performance difference. There is one not too far from where I live with 66k on it. Might go take a look!

BR's,

Mark


Take a look to confirm if you can, but the same RPO code means the same engine. I believe the similar early 2.8L motors for Saab and some others are the motors with single cam phasing.


 
quote
Originally posted by Rickady88GT:

I agree, but I also think that the owner of the car should not have to buy aftermarket stuff to prevent the burnt oil buildup whether it is in the intake, valves or valve covers. This is clearly an issue related to Direct Injection and poor crank case ventilation.
But basically my question is, can the vapors be redirected away from the intake system and improve ventilation?



Yes and no to the first question. No, you don't have to buy aftermarket products to prevent certain maintenance side effects from design. Yes, you do have to obtain necessary services to prevent problems that may develop as a result from routine use if you choose not to make improvements. You can buy the aftermarket fix, or pay to have the car serviced routinely instead. That's nothing new. The auto manufacturer has different goals than the consumer, there will always be things you can do above and beyond manufacturer recommendations that will improve and prolong the service life of your vehicle.

As Will pointed out earlier elsewhere, oil film is necessary on the cylinder walls, for all we know the oil allowed through the intake is deliberate to a degree to aide that process. The remarks about residue build up also point to oil quality. I've posted several times that these motors are very hard on oil and I'm confident on that stance given in addition to the potential for carbon build up on valves, you also have associated fuel dilution of the oil in DI motors. If you put cheap oil in it and run it until the monitor gets around to saying change it, you'll likely have more internal deposits. I've seen it in some, but not those using full synthetic. My oil has never come out in 3k miles use looking like it should have been left in longer.

When I checked the condition of my engine which there is a picture of somewhere, internally it is very clean, there is a slight layer of crust on the roof of the valve cover, but nothing of the sort on the heads. The build up on the valves was not significant enough for me to bother cleaning them at the time, so I didn't.

One of the turbocharged Camaros had the crankcase gasses vented to exhaust to combat blow-by, using the old round check valves that GM used to include on the cars years ago as part of the EGR system. I don't recall if the owner also added proper valve cover inlet vents to allow fresh air into the engine. The motor needs fresh air flow through it as the combustion gasses are exiting.

The catch can is far more practical than welding on attachments to accommodate that process.

[This message has been edited by Joseph Upson (edited 12-08-2018).]

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Rickady88GT
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Report this Post12-08-2018 10:20 PM Click Here to See the Profile for Rickady88GTClick Here to Email Rickady88GTSend a Private Message to Rickady88GTEdit/Delete MessageReply w/QuoteDirect Link to This Post

Just thinking, am I wrong to assume that the newest versions of the V6 have electric power steering and possibly even A/C?
If this is the case, the accessory belt system should be much less busy.

[This message has been edited by Rickady88GT (edited 12-08-2018).]

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