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View Full Version : Low hanging fruit and other newbie questions.



NewV
November 26th, 2006, 07:29 AM
Guys, new to the forum and EFI tuning wasn't sure the best place to post these questions. I've read thru the tutorials and think I have a good idea of what to do but like everyone else I need some quick wins to boost my confidence. I have an LS6 in a 05 CTS-V, my questions are:

1. Any custom OS templates available specific to this engine?

2. Do I NEED a WBO2 sensor to create a worthwhile tune or can I start without it and add it later once I get more experience?

3. Any advice on what to go after first for those quick wins? I'm looking for increased throttle response and HP of course but need daily drivability.

My car is stock except for CAI and Catbacks. Thanks in advance for any helpful tips or advice.

Garry
November 26th, 2006, 07:32 AM
Without a WBO2 you'll have a hard time dialing in your AFR decently ... it's $170 or so well spent ...
As for starters, just follow the AutoVE tutorial ... helped me shave off .2 without any changes to the car ...

TAQuickness
November 26th, 2006, 08:19 AM
Welcome to the forum NewV! Garry nailed it. Tuning without a WB is more difficult than using trims. www.greenlightmotorsports.com (http://www.greenlightmotorsports.com) has good deals on WB's.

NewV
November 26th, 2006, 11:35 AM
Ok, so I need a WBO2 unit. Assuming I get an LC-1 do you recommend I get the LM-1 logging unit or is it just as easy to log it direct to the Flashscan V1 unit?

TAQuickness
November 26th, 2006, 11:41 AM
the lc1 is all you need, but i hear the lm1's a re a bit easier to install.

jkg
November 27th, 2006, 01:13 AM
I also am a new user with 2004 CTS-V looking to have some fun with EFILive. I have played around with throttle response (throttle cracker and follower), which does change things, but not really affecting performance. I suppose the nest step is AutoVE tuning, although I am still entirely uncertain how much effect will be achieved with mostly stock engines like ours.

NewV
November 27th, 2006, 04:39 AM
I also am a new user with 2004 CTS-V looking to have some fun with EFILive. I have played around with throttle response (throttle cracker and follower), which does change things, but not really affecting performance. I suppose the nest step is AutoVE tuning, although I am still entirely uncertain how much effect will be achieved with mostly stock engines like ours.

Are you using a WBO2? If so which one?

SSpdDmon
November 27th, 2006, 05:59 AM
Had an LC1 (still do if you know someone looking for one). I moved onto an LM1 though because I tune other cars and it's a little easier to get in and out. Plus, there's not as much wiring to worry about.

As for your tuning questions...the best thing you can do at this stage is get familiar with the scanner/tuner software. Really understanding how the two work together and how to build the right maps is what will help you once you get a hold of a WB. For a simple bolt-ons LSx car, there won't be a whole lot you need to change. A little tweak to the fueling and maybe some minor adjustments to the spark table should do you. The rest is what I call "user preference" (ie fan settings, speedo adjustments, rev limiter adjustments, etc.).

jkg
November 27th, 2006, 02:26 PM
plan to get LM-1, based on what I have heard on this forum. I think it can be temporarily wired in place of a stock O2 sensor. I am still a little foggy on exactly what an Auto VE tune does. I am trying to learn the bits and pieces of the EFI Live software by experimenting, but it is hard to find enough time to devote to it. I am still looking for the authoritative write-up for a step-by-step tuning procedure.

So far, I have found that by replacing the stock throttle cracker table with the one from the Z06 vette (same engine), I can get the car to really slow down when I get off the gas in gear, instead of coasting along (makes the care a little rougher around the edges - more chevy and less cadillac). My next step is to copy the throttle follower as well, to see what that does to driveability. And I am jus delighted with a 160 thermostat and resetting the fan settings - car runs 180s instead of 210s now -

joecar
November 27th, 2006, 02:37 PM
...I am still a little foggy on exactly what an Auto VE tune does. I am trying to learn the bits and pieces of the EFI Live software by experimenting, but it is hard to find enough time to devote to it. I am still looking for the authoritative write-up for a step-by-step tuning procedure... The AutoVE tune uses the WBO2 sensor values to create a correction multiplier matrix which is then multiplied into the VE table;

each cell of this matrix is the correction multiplier for the corresponding cell in the VE table, and is obtained by the calculation of Commanded_AFR/Actual_AFR where Actual_AFR is read from the WBO2 sensor;

the AutoVE tune procedure first eliminates any other AFR influences, such as NBO2/closed loop and MAF sensor inputs;

the aim is to have the VE table "corrected" so that the actual AFR matches the commanded AFR;

once the VE table is corrected like this, then the AFR values commanded from the OLFA and PE tables will be seen as actual AFR's (i.e. what you enter into the OLFA/PE tables is what you will get in the exhaust);

it will also be helpful if IFR table contains the correct values (these can be computed using the spreadsheet); same concept: a correct IFR table means the actual fuelmass matches the fuelmass the PCM is requesting.

NewV
November 27th, 2006, 03:33 PM
joecar - Thanks for the explanation on the AutoVE. Glad to hear its not too far off from what I thought it did.

jkg - I am considering the 160 thermostat as well. On another forum I posted a question about it and one response was a little worrisome: "Another thing to consider is that the oil should normally operate around 212F or so. If the oil is kept well below 200F due to low coolant temps, moisture in the oil won't boil off as fast and that could lead to condensation and potential rust in the motor." May want to watch the oil temperature.

jkg
November 27th, 2006, 11:44 PM
The car seems to want to run at water temps in the 180s while crusing, higher when standing with the 160 thermostat. The oil temp gauge is notoriously unreliable on these cars, since it often runs many degrees higher than water temp, and was the subject of a TSB early on -- GM responded to concerns of unreliable oil temp readings by recalibrating the gauge, so that it reads closer to the water temp. This quieted the complaints, but makes the temp readings no more accurate.

Regarding the concern for water in the oil, running the car on the highway a bit should take care of any condensation. And the oil temp varies depending on where it is measured. It is probably much hotter around the main bearings, cooler in the pan. And I think it is better to run 180-190 on engine temp than 210-230. Other than just feeling cooler in and around the car, it is a first step toward making more power. The cooler the air intake, the denser the air (supercharger effect). The LS6 engine is particularly sensitive to air intake temp - on a cool day, even I can feel the difference in power.

Next step - Auto VE tune I guess.

TAQuickness
November 28th, 2006, 02:44 AM
Every motor will run better when it's cooler outside. BUT - you still need to run the motor at it's normal operating temp.

eboggs_jkvl
November 28th, 2006, 06:17 AM
joecar - Thanks for the explanation on the AutoVE. Glad to hear its not too far off from what I thought it did.

jkg - I am considering the 160 thermostat as well. On another forum I posted a question about it and one response was a little worrisome: "Another thing to consider is that the oil should normally operate around 212F or so. If the oil is kept well below 200F due to low coolant temps, moisture in the oil won't boil off as fast and that could lead to condensation and potential rust in the motor." May want to watch the oil temperature.


That would be correct information. THe car runs best on cold air not cold engine. Stick with the stock t-stat temperature.

Elmer

dfe1
November 28th, 2006, 02:34 PM
I don't think running too cool is ever an issue unless you live in the frozen north. I don't know of any LS-powered vehicles that run at thermostat temp. I have 160-degree stats in several vehicles, and all run at least 175 even at 40-degrees ambient. Running on the interstate at 60+ ambient, coolant temps are always 180-185. Oil temp is more a function of engine load than coolant temp. As soon as you start driving, oil temps climb.

joecar
November 28th, 2006, 02:36 PM
Yes, oil temp outpaces coolant temp.

SSpdDmon
November 29th, 2006, 04:39 AM
The one thing about the t-stat debate I don't get is this...

The main arguement against running a cooler t-stat is that engines run at higher temps to cut down moisture in the block/oil/etc., right? In other words, if an engine runs at 212*F (100*C) it will 'boil' off any water in the system. So, we're basically talking about accelerating the evaporation process.

I don't know about you guys, but I don't live in the rainforest. Therefore, I would assume the amount of moisture that can collect in the engine is somewhat minimal to begin with. This little bit of moisture will still evaporate at slightly cooler temp. **A quick test...stick a pot on the stove with a teaspoon of water and heat it up (don't let it boil). It will evaporate rather quickly - faster than if left at room temps.** In the engine, the moisture may burn off slightly faster at 212*F compared to 180*F. But, it will still burn off.

Personally, I'd rather run a cooler motor, change the oil every 3K (just to be safe), and make a little more power with less risk of detonation. Until someone shows some solid proof of it causing problems, I don't plan on changing my ways...

TAQuickness
November 29th, 2006, 05:57 AM
SSpdDmon - good perspective.

For the sake of splitting hairs: Teaspoons are much cheaper to replace than engines :D But seriously, There is less potential for water to damage the engine the faster it evaporates out.

At some point on Google I had found a very good explaination of the effects of running the engine cooler than designed. I'll post it if I can find it again. In short, the cooler engine made more power (5 or 10 hp), but lived a much shorter life.

I would also bet that most of us build new motors long before any negative signs of a cool engine become appearant.

jkg
November 29th, 2006, 07:49 AM
The lower thermostat allows me to run engine temps around 20 degrees cooler. This gives the option to increase power slightly through a good tune, but also decreases the air intake temp (throttle body has coolant through it), which may increase power a little as well. Probably not enough to notice any driveability difference. In my case, I just like having the engine run cooler -- as an old V8 fan, seeing water temps at 220 or higher makes me unhappy.

On the other hand, my father found that dropping the engine temp was very helpful in his z06 corvette in keeping interior temps down - the transmission tunnel would radiate a lot of heat...

neil
November 29th, 2006, 05:48 PM
Found this on the web. It may be of some interest.
Can't remember who produced it.

Proper Coolant Temperature and Camshaft Life!

Have you ever tried to find what proper coolant temperature is for most automotive engines? There are a lot of people who think they know, but it is difficult to find specifics, even in textbooks. We know we want the intake air to be as cold as possible (for best power) because cold air is denser (there are more oxygen atoms per cubic foot). The coolant temperature, however, is a different matter. The internal combustion engine changes chemical energy stored in gasoline into heat energy that is focused on the piston tops. If the cylinder heads and engine block are too cold, they will absorb much of the combustion heat before it can be used to push the piston down the cylinder. If the engine gets too hot, engine lubricants can break down, as well as overheating of the intake charge can lead to detonation, etc.

It turns out that coolant (usually a 50/50 mixture of coolant and water) has some fantastic properties that are ideal for use in engines. With a properly pressurized cooling system, coolant will not freeze until –30°F, and it won’t boil until +270°F (new oils don’t start to break down until well over 270°F). With these characteristics, engine designers have decided that engines should operate at approximately 210-215°F. Why, you ask? Well, it has to do with operating the engine at a high enough temperature to boil water out of the oil after the engine is cold started. If you have dew on the grass, it is certain that you have water in your oil, as the crankcase is open to atmospheric pressure! You can either remove the water by draining it out the bottom of the oil pan (remember the oil floats on water) or run the engine long enough and hot enough to boil the water out of the lubrication system. Years ago, coolants weren’t as sophisticated and engines were run at 165-180F, but the oil was changed every 1000 miles or so. That’s why many old timers think engines should run at 165-180F. Have you ever noticed that Ford doesn’t put temperature marks on their gauges? They just mark C for cold and H for hot and write “normal” through the center. If you hook up a scan tool to a GM, you will often find that the gauge reads much lower than the coolant temp sensor. That is because they know most drivers don’t understand how hot an engine should run.

So what does this have to do with camshafts? Many enthusiasts erroneously think that the colder their engine runs the better! If they are not running the engine hot enough to boil the water out of the oil, the oil becomes contaminated and the lifter/cam lobe interface is the highest load point in the engine. Engines running too cool can contribute significantly to camshaft and lifter failure. Think about it: What good does it do to use the most expensive synthetic oil and then run the engine so cold that it is contaminated by water vapor??!! Another point, piston manufacturers’ piston-to-wall clearance recommendations assume you will be running the fully warmed engine at 200°+F. Run the engine too cold, and you could see some scuffed pistons because the cylinders had not expanded enough to provide clearance.

If your engine will only run its best at the drag strip with the engine at 165°F, you probably have too cold of a spark plug heat range and you are probably jetted way too rich! If you keep the engine hot (not the intake charge), you will be using more of the heat energy in the gasoline to make power instead of just heating up your block. It does take “tuning know-how” to run an engine at 200-210°F, but you might be surprised how well and how long it runs when you do!! One final point - running a computer managed engine at 165°F compared to the factory 210°F will often cost you as much as 4 MPG. The reason for this is that the computer thinks that the engine is not off the “choke cycle” and it is still putting out a rich mixture! Check the science on this and don’t pay attention to the “old wives tales” of the past. Materials and lubricants are much better and different today than they were in the past!!

I run the fans at stock and I run the stock Thermostat.

Regards,

Neil.

zrx1200
November 29th, 2006, 09:10 PM
i think the reasons for running engines hot is purely for emisions....

SSpdDmon
November 30th, 2006, 02:46 AM
Found this on the web. It may be of some interest.
Can't remember who produced it.

Proper Coolant Temperature and Camshaft Life!

...If you have dew on the grass, it is certain that you have water in your oil, as the crankcase is open to atmospheric pressure!...

Regards,

Neil.

I still stand by my previous statement that water will still evaporate below 212*F (100*C). The boiling point of water is not some magic evaporation number that opens a flood gate. The more excited the molecules of water are as temperature rises, the faster it will evaporate. At least, that's what appears to happen when I see the water in my world.

But, the quote above raises another point that I don't agree with. How are our crankcases exposed to atmospheric pressures? Last time I checked, my LS1 has a PCV system that is like a one-way street. It will use manifold vacuum to relieve positive crankcase pressure. But, I've never heard of it flowing the other direction. The only time I can think of outside air entering the crankcase is when I change the oil.

Maybe I'm wrong on this one...but my gut has me thinking that big, long write-up is bull$h!t. No offense neil. ;)

VetPet
December 6th, 2006, 03:04 PM
An interesting topic to say the least. I'd have to say that the engine is not completely 'air tight' to begin with so there's no doubt in my mind that moisture will find it's way into the crankcase. Some blowby gets into the crankcase when the engine is running and part of that is made up of air that has some moisture in it. When you shut off your car and the engine starts to cool down you're going to get condensation at some level occurring. The next time you start your car this condensation (water) will have made it's way into your oil pan. When you start your car again you're going to need enough heat to convert water into a vapour that will actually get recycled into the combustion process and burnt.

Todays engine technology is vastly different than our old musclecars. When were any of those blocks and heads aluminum? Even when you installed aluminum heads it was never a good idea to start driving the car until the heads had sufficient time to warm up. Also, aluminum has different heat retention properties than cast iron. Without making this longer, we're dealing with different oil technology, engine design technology, different materials and other properties that have changed the conventional thinking of the past. I believe that changing the stat is not necessary and in the end, can do more harm than good.

:cheers: