Accel Gen 7 start up and high rpm problem

[supremeefi]

Hey Jim, as mentioned send me those logs and we'll check it out.

Your lean spike is because of your VE, it's all over the place and makes no sense as I mentioned to you yesterday. Normally it's not the ECM that's the problem but that's what almost always gets the blame.

As far as self tuning, the Accel makes doing it yourself much easier than most. You simply datalog it and drive it like you would anything else. Then come back and do a "Fuel Overlay" that will tell you where you just were on the VE tables. Take the cells and correct them accordingly, either individually or in groups. Normally takes less than an hour and you can customize your map as well for extra lean cruise etc, can't do that with the EZ stuff.

And don't forget the benefits of total spark control, and from cold to hot running. None of the self tuning stuff has that either.

[1Bad68Cat]

Originally Posted by supremeefi

As far as self tuning, the Accel makes doing it yourself much easier than most. You simply datalog it and drive it like you would anything else. Then come back and do a "Fuel Overlay" that will tell you where you just were on the VE tables. Take the cells and correct them accordingly, either individually or in groups.

Can you explain how to do the fuel overlay. I would like to eliminate the lean spikes I am seeing in my setup. Thanks.

[supremeefi]

Easy, set your datalog for 20 min or so, remember it registers in seconds.
Use these parameters,
RPM
TPS
MAP make sure you pick the same one as your tables, i.e. KPA, % etc.
O2 Feedback
O2 correction
Timing

Make sure you've set your rpms in the tables (F2, F3, F4) to reflect your driving. No sense in having tables that go to 6500 if you're not going to run it there, you're wasting resolution. Store your existing cal, put your Acceleration modifier at 1.0 across the graph. Enable the Datalog, drive the car making an effort to accelerate smoothly and with no excessive pedal movement. hold for a second or two at various loads and rpm's. When the datalog is done it will automaticlaly store it by dating it, i.e. 06132011 etc.
Then open your cal, press F2, go to "Overlay". Click on the datalog you just did. All the cells that you hit during your drive will be highlighted in blue. Down on the bottom it will tell you the actual O2 and correction as well as the other parameters you picked for the log. By pressing the page up or page down keys on your computor keyboard it will move the cells around the graph in the order they were stored. Correct them accordingly and send to the ECM. When you're done then address your transient fueling, the acceleration modifier, TPS ROC, and Tau. Make sure you've set your air/fuel table to the values you want where and when you want them beforehand. And obviously make sure it's up to temp, timing is good and there are no other modifiers in use.
Once you do it the first time it gets easier, you can do different parts of the map, full throttle, cruise etc all at once.
Then fine tune from there, air/fuels, spark timing etc. And remember all fueling calibrations are taken from the VE, if you change that you change other areas, that's why you do this, the "Steady State" stuff first.

When done right I'll put the drivability of the Accel up against anything, even systems that cost twice as much.

Hope this helps.
Mark