TCC lockup delay

[damanx]

I think I've figured out what one of my biggest issues might be.

I strongly believe it's the TCC lockup delay.

Having looked at a few bins, the 3rd and 4th gear lockup speed, as well as the lock up delay values seem to be all over the place.

Trying to figure out where that should be is the question.

I have changed the lockup delay value from 0 seconds to 5 seconds and the shifting seems much better, but, I believe it's still too soon.

It appears this value affects both 3rd and 4th gear.

I am running a 3.4l engine, 700r4 trans, and 3.73 rear.

Is there an easy way to find out what bins were used with 3.73 rear ends?

Any recommendations?

I am going to bump the delay up to 10 seconds and see how that works.

[damanx]

O.k. I think I've figured it out.

Having looked at multiple BINs between the 8062 and 7747 ecm's, I've seen a variety of TCC 3rd and 4th gear lock speed values and TCC lock delay values.

Correct me if I am wrong, but based on my possibly over analytical tendencies, I believe the value of the TCC lock delay is the most important follwed by the 3rd and 4th speed at which the TCC can lock.

Why is this important?

Because my engine had a vacuum switch that controlled the TCC solenoid.

From day one of the carb to efi conversion, it seemed that I could never get the timing dialed in, especially under load.

It turns out that, and I believe this to be the root cause of many days of frustration, that I was using bin's with the TCC lock delay set for a very short time period.

I started out with the 8062 ecm and then moved to the 7747 ecm based on the fact that the 7747 is hacked way more than the 8062. But then it seemed that in addition to the TCC issues listed above, that the programming for the $42 was not quite right for the 60v6 engine.

An example of that would be the question of parameters that deal with time of exhaust flow from the cylinder to the o2 sensor. I don't recall specifically what those were called at the moment.

In any case, I decided a couple of weeks ago to go back to the 8062 with a 2.8 60v6 BIN.

I've installed a 4.3 throttle body and have tweaked the blm and timing tables and have had a lot better results in a shorter time period than I have with the 7747 ecm and $42 bins.

Anyways, back to the TCC lock delay value.

When controlled by a switch using manifold vacuum, I recall the vacuum switch closing around 17 inches. I realized when watching TunerPro and WinALDL that the TCC locked too soon and found that the BIN I was using had the delay set to .10 second.

I changed that value to 5 seconds which resulted in the shifting, loading and knock counts improving substantially. With the delay set to 5 seconds, I am assuming that is giving more time for the vacuum and loading to stabilize as I don't know if the 8 second clock starts at the time the 3rd gear speed is reached and resets upon reaching the 4th gear speed, or if it continues regardless. I'm thinking the latter.

I'm going to bump the delay up to 8 seconds and see if that holds off the TCC lockup until the vacuum is higher than where it's locking up now.

All this info is for anyone who cares.