TWEECER help, ASAP!

[Toolman]

Okay, my ECT is not working right. Keeps throwing code 118, ECT @ -40 or something. This sensor and it wires are very close to my DP gasket, and it blew last year and melted a few things in the vicinity, so I have a feeling the wiring harness was damaged right here. My fan does not come on when it should, so something is amiss.

Anyway, in the functions tab, there is a 'WOT spark advance vs ECT' tab. Stock setting are as follows: -256F=10, -256F=10, 0F=10, 50F=0, 230F=0, 250F=-5, 254F=-5.


So, since it is already 85F ambient, and since I will not get hotter than 230, what is the harm in setting this function as follows: 0 across the board until 250F, where it continues as stock? Because if my ECT is giving the EEC a reading of -40, wont I be adding 10 degrees all the time @ WOT?

 

[60kmaintenance]

First off what's the total advanced before the "WOT spark advance vs ECT" ? What RPM is your full advance at? Are your secondaries opening at a specific time?

Please fill me in that information first.

I don't think this is a question of where to set it relative to original stock ECT working situation, as it is spark advance degrees for a turbocharged engine.

Also is it possible to just make a fan switch that you operate? That way you can even leave it on when the car is off, for a few minutes, help cool down some water. It's nice to have that control on an engine that gets fairly warm. When the vehicals is just baking cause its 100 degrees out, and you know the engine is going to get hot fast, why not turn the fan on and keep things cooler before they get hot, and then you have double the work to cool them down.

 

[Toolman]

Depends. There is a 'spark advance rate vs RPM' function as well as a 'WOT spark advance vs RPM' function. So talking about WOT only, the range is from 16-28, depending on RPM.

I just ran it, and it did not seem to make one iota of difference. Back to the drawing board.

Wonder if I got a bad MAF?

 

[60kmaintenance]

28 degrees advanced is a LOT of advancement for a turbo charged engine....

Try making 0 degrees for WOT at all temperatures. You only run the thing when it's warm any how right? I should hope so..... I would try limiting total advance to hmm how about 21 degrees to begin with, see how it reacts. Turbo charged engines normally function better with even into the ******** timing.

What RPM does the turbo spool at ?

You might think I sound radical, but I would play with the timing advancement A LOT. I would even estimate you'll end up not wanting to build over 8 degrees advanced WOT at 7000rpm..... Start the engine when it builds boost down at like -2 and slowly work toward 8 degrees. I understand that you have two variables determining this, so it'd take some work to re-map it all. Also if you don't build boost until like 1500rpm, at all.... You could certainly start the advanced in a higher range, as until you build boost advancement will play a small roll in it's ability to quickly increase RPM and build boost. This only helps you when your starting from 0mph of course. That and you can burn the clutch a little to get boost prior to it.... So the idle with zero boost just be around stock.

If you decide to be a little more daring, and radically change the spark advanced WAY lower, you might just find you can go out and turn that *** or press that button on your boost controller up a little.....

Oh yeah, I have no idea if you have a bad MAF, you didn't describe AT ALL what your car is doing that's making you fllip through Tweecer settings. There is thousands of possiblities to any thing, and if we don't even know the problem, how do you expect us to help ?


If it's leaning out, can't the oxygen sensors actaully control that a little bit? Hm I'm just thinking for a better burn on your boosted car, seriously play with the spark advanced. That might even lean out the readings the O2 sensors get, and ease your tuning for fuel richness. I imagine the O2 sensors can actaully fight you on that one.

Do you have the means to test the MAF? I think you might of anwsered your own question now that I remmeber your problem.

 

[60kmaintenance]

Oh yeah, I have no idea if you have a bad MAF, you didn't describe AT ALL what your car is doing that's making you fllip through Tweecer settings. There is thousands of possiblities to any thing, and if we don't even know the problem, how do you expect us to help ?


If it's leaning out, can't the oxygen sensors actaully control that a little bit? Hm I'm just thinking for a better burn on your boosted car, seriously play with the spark advanced. That might even lean out the readings the O2 sensors get, and ease your tuning for fuel richness. I imagine the O2 sensors can actaully fight you on that one.

Do you have the means to test the MAF? I think you might of anwsered your own question now that I remmeber your problem.

 

[60kmaintenance]

Wait is the problem that it's leaning out ?

 

[60kmaintenance]

If it's leaning out, can't the oxygen sensors actaully control that a little bit? Hm I'm just thinking for a better burn on your boosted car, seriously play with the spark advanced. That might even lean out the readings the O2 sensors get, and ease your tuning for fuel richness. I imagine the O2 sensors can actaully fight you on that one.

Do you have the means to test the MAF? I think you might of anwsered your own question now that I remmeber your problem.

 

[60kmaintenance]

Er I know I keep posting, but you don't have any more problems, electrical or any thing do you ? They might sound silly or like they could never have any thing to do with any thing else electrical, but you never know.

 

[Sho-Driver]

28 degrees advanced is a LOT of advancement for a turbo charged engine....

Try making 0 degrees for WOT at all temperatures. You only run the thing when it's warm any how right? I should hope so..... I would try limiting total advance to hmm how about 21 degrees to begin with, see how it reacts. Turbo charged engines normally function better with even into the ******** timing.

28 degrees is a lot of timing, but if the motor in not retarding timing, run it. Timing is where you'll see power gains with boosted cars. I was running 28* timing advance, but now have limited it to 25*.

I would not retard timing below 0, period. General rule of thumb is retard timing 1 degree for every 2 PSI of boost (starting with the stock curve). This helps if you graph boost vs. RPM, which can be done with the TwEECer. The computer will retard the timing up to 8* from where ever it is set at. At what ever RPM he's running 28* advance, the computer can knock it down all the way to 20* if detonation is happening.

You might think I sound radical, but I would play with the timing advancement A LOT. I would even estimate you'll end up not wanting to build over 8 degrees advanced WOT at 7000rpm.....

That would take a considerable amount of power away from Tim. You can run a good amount of timing when boosting. The key is to run AS MUCH timing as you can without detonation. This is where intake charge cooling will play a big role. Tim has an intercooler and an I/C sprayer, he can get away with some decent timing advance.

Start the engine when it builds boost down at like -2 and slowly work toward 8 degrees. I understand that you have two variables determining this, so it'd take some work to re-map it all. Also if you don't build boost until like 1500rpm, at all.... You could certainly start the advanced in a higher range, as until you build boost advancement will play a small roll in it's ability to quickly increase RPM and build boost. This only helps you when your starting from 0mph of course. That and you can burn the clutch a little to get boost prior to it.... So the idle with zero boost just be around stock.

All he needs to do is graph boost vs RPM and map timing out from there. For a first tune to work with, I would back off timing to about 22-24 degrees at max and work up from there until you see detonation. You can watch detonation on your TwEECer by watching timing advance. You know what timing is supposed to be at a given RPM, you just make sure it does not kick back 8* and you're not going to blow a piston.

Since you're tuning the motor for "operational temperature", there is no need to mess with spark advance vs ECT.

Oh yeah, I have no idea if you have a bad MAF, you didn't describe AT ALL what your car is doing that's making you fllip through Tweecer settings. There is thousands of possiblities to any thing, and if we don't even know the problem, how do you expect us to help ?

For the air he is flowing, he should have a Lightning 80mm MAF as a minimum. He can also watch exaclty what the MAF is doing on the computer. Generally, it's not the functionality of the MAF that is the problem, it is the fact the computer does not have the correct transfer function, although it may be close. This is where tuning starts happening.

If it's leaning out, can't the oxygen sensors actaully control that a little bit? Hm I'm just thinking for a better burn on your boosted car, seriously play with the spark advanced. That might even lean out the readings the O2 sensors get, and ease your tuning for fuel richness. I imagine the O2 sensors can actaully fight you on that one.

The O2's will monitor the exhaust and apply KAMREF values. These values will be learned in CL and applied to OL because the O2's are not monitored during WOT.

 

[Axianator]

Okay, my ECT is not working right. Keeps throwing code 118, ECT @ -40 or something. This sensor and it wires are very close to my DP gasket, and it blew last year and melted a few things in the vicinity, so I have a feeling the wiring harness was damaged right here. My fan does not come on when it should, so something is amiss.

Given the fact that both V6 SHO strategies utilize ECT sensor readings for a good number of their functions and tables (many of which are not yet accessible with the existing version of CalEdit), I would highly recommend that you repair and replace both your ECT sensor and it's harness as soon as you possibly can, Tim. Proper ECT sensor readings are crucial when calculating proper fuel and spark delivery under many different scenarios, something which isn't possible if your ECT isn't reporting the correct voltages and a point which becomes doubly important when discussing a boosted application.

That said, I would recommend that you set your 'WOT Spark Advance vs ECT' function to a value of 0 across the board until such a time when you are able to repair your ECT sensor harness and verify that the correct readings are being fed back to the EEC (via CalCon).

There is a 'spark advance rate vs RPM' function as well as a 'WOT spark advance vs RPM' function.

The 'Spark Advance Rate vs RPM' function is used to determine how much advance is applied within a given time frame, while the 'WOT Spark Advance vs RPM' is the advance curve that is used before the other adder/retard functions once throttle position (as indicated by TPS readings) has exceeded the specified WOT breakpoint.

When modifying these two functions, keep in mind the following:

- while the factory MTX advance rate curve could stand some improvement, I would not exceed more than 2 degrees/sec at any point in the curve when modifying this function, especially in a boosted application. Doing so could result in the EEC advancing the timing too quickly and could easily encourage preignition on some setups.

- the WOT spark advance function is also supplemented by the other adder/retard functions you see grouped in the Functions listing (ECT, ACT, etc). As such, you should not look solely to the WOT spark advance function when attempting to calculate total WOT advance, nor should you be surprised if the amount that you are seeing is more (or less) than what you've entered via the WOT spark advance function.

All he needs to do is graph boost vs RPM and map timing out from there. For a first tune to work with, I would back off timing to about 22-24 degrees at max and work up from there until you see detonation. You can watch detonation on your TwEECer by watching timing advance. You know what timing is supposed to be at a given RPM, you just make sure it does not kick back 8* and you're not going to blow a piston.

While the above advice regarding boost vs. RPM mapping is quite sound, I wouldn't recommend utilizing the above method of knock detection on any SHO unless you know exactly how much advance you should be seeing for a given RPM (a job that is not easy thing to accurately pull off, even on an MTX with it's reduced number of adder/retard functions). IMO, the better solution would be to purchase, install and adapt a seperate but dedicated knock link monitor to your setup and monitor the readings via CalCon. Doing this will allow you to datalog the knock readings with the rest of your variables (allowing you to map the knock readings against RPM, load, etc.) and will allow you to be more accurate than you would be if you utilized the former method of "assuming" your total amount of advance.

The computer will retard the timing up to 8* from where ever it is set at. At what ever RPM he's running 28* advance, the computer can knock it down all the way to 20* if detonation is happening.

Actually, the maximum amount of spark retard for all V6 strategies is 10 degrees.