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ctuinstra's City Goblin - 07 SS/SC donor 2.0

ctuinstra

Goblin Guru
I've been working on tuning the car with HP Tuners since changing the fuel system over to a boost-reference fuel pressure system and changing the type of injectors. I ran into a lot of little abnormal issues along the way. First the return line filter kept getting clogged not allowing fuel to return and the pressure would sky-rocket to 90PSI! Once I figured that out, the fuel pump itself went out (and was less than a year old). After that my wideband O2 sensor died (do not think you can get away without running the heating element of the O2 sensor for very long). I upgraded to a newer version of O2 sensor (from 4.2 to 4.9) and a new AEM gauge. That helped a lot!

Most of the issues I was having using HP Tuners what the data logging would contain such a wide varying set of numbers and I was chasing the numbers all the time. In one log, it would want to lean it way out in one cell and the next time would want to richen it up, then lean it out, and I could never get close to stoich and keep it there. I ends up it has a lot to do with driving style and how you log it. I won't go into great detail, but I learned a hell of a lot in a short amount of time. As an example, while driving and you close the throttle to use the engine braking, that really screws up the logging! Manuals are hard to drive and tune!

Tonight I finished up the VE tuning and worked on the MAF tuning. Same thing, I depends a lot on how you run the car to get the best results. But I finally got to the point that I don't think it's going to get much better. And all I can say is DAMN! I'm happy with the results! I have finally got rid of the choppy throttle, occasional backfire, and other issues. It's no longer running pig rich. I'm sure it's not perfect, but it is a hell of a lot better than it was. Later this fall, I'm going to work on the tuning the timing for just a bit more HP.
 

Ross

Goblin Guru
...
As an example, while driving and you close the throttle to use the engine braking, that really screws up the logging! Manuals are hard to drive and tune!
Congrats Chad! It is great to get things working well.
I have learned to scrutinize the logged data before I apply it to my tune. If the data is wonky, I just throw it out, but I have learned to: 1. wait until the engine is up to temperature, and 2. Don't hit the rev limiter. Both will make the data wonky.
Engine deceleration is okay, if you turn off deceleration fuel cut off (DFCO). I do this by setting the DFCO Enable ECT = 300F (engine coolant temp).
Once you do that, then the engine stays at stoichiometric during deceleration.
 

ctuinstra

Goblin Guru
Congrats Chad! It is great to get things working well.
I have learned to scrutinize the logged data before I apply it to my tune. If the data is wonky, I just throw it out, but I have learned to: 1. wait until the engine is up to temperature, and 2. Don't hit the rev limiter. Both will make the data wonky.
Engine deceleration is okay, if you turn off deceleration fuel cut off (DFCO). I do this by setting the DFCO Enable ECT = 300F (engine coolant temp).
Once you do that, then the engine stays at stoichiometric during deceleration.
I put in filters to help filter out some of the junk. Then after changing the tables, I would manual smooth some areas. That helped a lot.

I did disable the DFCO the same way you described. Maybe there is more that needed to be done to make sure it doesn't come in to play. Either way the commanded and actual would be way off in certain areas and just changing the driving style would affect it.

This is a poor example (it's the only saved log file that kind of shows it). Notice the really lean at 15 MAP? He would get that by letting off the throttle and letting the engine braking slow the car down (hence the 15 MAP= high vacuum). This is not my final log, just one that I had saved. At least it isn't that lean under load and higher RPMs.


15814
 

ncgoblin

Well-Known Member
I've been working on tuning the car with HP Tuners since changing the fuel system over to a boost-reference fuel pressure system and changing the type of injectors. I ran into a lot of little abnormal issues along the way. First the return line filter kept getting clogged not allowing fuel to return and the pressure would sky-rocket to 90PSI! Once I figured that out, the fuel pump itself went out (and was less than a year old). After that my wideband O2 sensor died (do not think you can get away without running the heating element of the O2 sensor for very long). I upgraded to a newer version of O2 sensor (from 4.2 to 4.9) and a new AEM gauge. That helped a lot!

Most of the issues I was having using HP Tuners what the data logging would contain such a wide varying set of numbers and I was chasing the numbers all the time. In one log, it would want to lean it way out in one cell and the next time would want to richen it up, then lean it out, and I could never get close to stoich and keep it there. I ends up it has a lot to do with driving style and how you log it. I won't go into great detail, but I learned a hell of a lot in a short amount of time. As an example, while driving and you close the throttle to use the engine braking, that really screws up the logging! Manuals are hard to drive and tune!

Tonight I finished up the VE tuning and worked on the MAF tuning. Same thing, I depends a lot on how you run the car to get the best results. But I finally got to the point that I don't think it's going to get much better. And all I can say is DAMN! I'm happy with the results! I have finally got rid of the choppy throttle, occasional backfire, and other issues. It's no longer running pig rich. I'm sure it's not perfect, but it is a hell of a lot better than it was. Later this fall, I'm going to work on the tuning the timing for just a bit more HP.
Nice work man I know this was a pain but you learned a ton. I have actually paused on upgrading cams and springs because of how reliable my tune is at this point trying to enjoy the power that I have and its actually kind of nice just cruising and knocking out a few Auto-X events without worrying about blowing up engine for now.

Its great to have knowledgeable community.
 

Ross

Goblin Guru
Wierd. DFCO is still active on your log file.

To de-mystify tuning:
I looked up the Volumetric Efficiency (VE) table, (Which is what Chad was tuning)
and the top X axis is intake Manifold Absolute Pressure (MAP) in kilopascals (KPA). 100 KPA = 1 atmosphere (14.7 PSI), 15 KPA is 15% of atmospheric.
and the side Y axis is engine RPM.
The numbers in each cell are normally the airmass, but in this chart, it looks like Chad has the air:fuel ratio, where 17:1 is lean, and ~14.5:1 is stoichiometric, and 12:1 is rich?
 
Last edited:

Karter2026

Goblin Guru
I've been working on tuning the car with HP Tuners since changing the fuel system over to a boost-reference fuel pressure system and changing the type of injectors. I ran into a lot of little abnormal issues along the way. First the return line filter kept getting clogged not allowing fuel to return and the pressure would sky-rocket to 90PSI! Once I figured that out, the fuel pump itself went out (and was less than a year old). After that my wideband O2 sensor died (do not think you can get away without running the heating element of the O2 sensor for very long). I upgraded to a newer version of O2 sensor (from 4.2 to 4.9) and a new AEM gauge. That helped a lot!

Most of the issues I was having using HP Tuners what the data logging would contain such a wide varying set of numbers and I was chasing the numbers all the time. In one log, it would want to lean it way out in one cell and the next time would want to richen it up, then lean it out, and I could never get close to stoich and keep it there. I ends up it has a lot to do with driving style and how you log it. I won't go into great detail, but I learned a hell of a lot in a short amount of time. As an example, while driving and you close the throttle to use the engine braking, that really screws up the logging! Manuals are hard to drive and tune!

Tonight I finished up the VE tuning and worked on the MAF tuning. Same thing, I depends a lot on how you run the car to get the best results. But I finally got to the point that I don't think it's going to get much better. And all I can say is DAMN! I'm happy with the results! I have finally got rid of the choppy throttle, occasional backfire, and other issues. It's no longer running pig rich. I'm sure it's not perfect, but it is a hell of a lot better than it was. Later this fall, I'm going to work on the tuning the timing for just a bit more HP.
I wish I had the drive to try to learn the tuning part of this. I am battling some of the same problems as you. Rich, Surging idle ( searching for stoich), and a intermittent dead spot as the boost starts to come in. I am just too busy right now with some home water issues and general life to try to tackle this. The car is drive able but not right.
 

ctuinstra

Goblin Guru
I wish I had the drive to try to learn the tuning part of this. I am battling some of the same problems as you. Rich, Surging idle ( searching for stoich), and a intermittent dead spot as the boost starts to come in. I am just too busy right now with some home water issues and general life to try to tackle this. The car is drive able but not right.
When you get to that point, I and others can help to get you a better tune.
 

ctuinstra

Goblin Guru
The next thing I'm trying to figure out is why there is gap in the throttle at idle. When it's idling, we cannot slowly step on the pedal and get the idle to go from say 800RPM to 900 or 1000RPM. No matter how carefully and slowly you press the pedal, it won't change and then all of sudden just up to 1100 or 1200RPM. This makes it tough to do very slow cruising. It's either on or off. I don't think there is anything I can do as far as a tune goes. I may take it in to see if Tech2 or something can calibrate it. I can scan the pedal position and the electronic throttle position and they show the exact same as I'm describing. The pedal position sensor will show small increases in percentage but yet the electronic throttle will not change until the pedal is around 11-12%.
 

Desert Sasqwatch

Goblin Guru

Or maybe something like this could help?

 

ctuinstra

Goblin Guru

Or maybe something like this could help?

I'll look into that and give it a try. Thanks!
 

ctuinstra

Goblin Guru
Kaleb took the car out for an hour long drive today and logged while he was driving. This is with after the tune and all the settings back to normal driving. I could not be happier with the final results. Sure a guy could try and tweak the last little bit but there is a point of diminishing returns.

This graph is the LTFT (Long Term Fuel Trims) and is the ECM fine tuning the AFR (Air Fuel Ratio). The closer to zero the better, however you will never get zero especially since weather, altitude , and many other factors will cause this to be adjusted. It's just a bit rich on the high end but I would rather it be rich there and let the ECM take out fuel than be the other way around.

As Ross mentioned, the columns are the MAP (Manifold Absolute Pressure). Low numbers are vacuum (idle) and atmosphere is 101kPa, so anything about 101 is boost. The rows are the RPM. You cannot hit every cell and those that are blank is because he never hit that cell.

15833
 

ctuinstra

Goblin Guru
While he was out, he notices a slight looseness in the rear again! UGH! I just fought this and thought we had it fixed. As it turns out, we did have that fixed by tightening up the strut to hub bolts. This time it's the lower ball joints bolts. I thought those were tight and even had a locking jam nut on them (thanks Adam for the notice). But I guess there was just enough wiggle room in the taper. So I tightened the heck out of the pinch bolt! And now it solid as hell! It feels good to chip away at a few of these little issues. We are getting this thing so dialed in. It really feels good.
 

Karter2026

Goblin Guru
This could help me also. Since I went to the LSJ throttle body when installing the S/C
 

OptimizePrime

Well-Known Member
I did disable the DFCO the same way you described. Maybe there is more that needed to be done to make sure it doesn't come in to play. Either way the commanded and actual would be way off in certain areas and just changing the driving style would affect it.
Check this table. 0-2 columns set to 0 all the way down, keep 3 at 15. That should do it

15841


This is for an LNF but I would imagine the same would apply for the LSJ. This topic starts at 6:05 but the whole video could help with additional details.

 

ctuinstra

Goblin Guru
Check this table. 0-2 columns set to 0 all the way down, keep 3 at 15. That should do it

This is for an LNF but I would imagine the same would apply for the LSJ. This topic starts at 6:05 but the whole video could help with additional details.

The Torque Management isn't the same between the two. ZZP set this table to all 100 giving max torque at all RPM and desired torque ranges. Made the car horrible to drive. The throttle was way to touchy. This is not stock but a happy medium. I may have to play with this to see if it makes any changes and I can find a setting that works but is still driveable.

15842



15843
 

ctuinstra

Goblin Guru
Changing the torque management didn't seem to have any effect. This short video shows the relationship between the pedal position and the throttle. Notice that from idle, I cannot slowly rev up to anything less than 1500RPM. It's at a slightly high idle because the engine was cold. But I cannot hit say 1200RPM.

It seems the magic mark is around 7-8% pedal and then all of a sudden the RPMs jump up from there to 1500.


 

ctuinstra

Goblin Guru
Everyone else is updating their builds, I guess I should update ours also; although there isn't much"building" going on anymore.

Kaleb was home this weekend and took the car out both Saturday and Sunday. I couldn't be happier with it right now. With the tune its running the best it ever has. Starts great, doesn't backfire, it's not running rich and even smells mostly clean even without a cat. The handling is so much better now that we have the suspension issues resolved and the alignment spot on. We are getting a small amount of popping from the upper helm joints when first applying the brakes. And the valve cover rubber gasket is leaking a very small amount, because of this, I may go back to the vacuum line on the carankcaae vent to help reduce a build up of pressure in the valve covers.

Just going to enjoy it this fall and have a "upgrade" planned for this winter. Next week Kaleb wants to take it back to college with him to ride some of the local roads.

IMG_0193.JPG
 
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