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View Full Version : Trans/TCC tuning questions -- AFR side effects?



turboberserker
February 26th, 2006, 07:21 AM
I've got a pretty aggressive fuel economy tune going and have started working on the tranny and TCC settings.

I have it shifting early and then locking up the TCC to keep it below 1500 rpm most of the time with an occasional peak to 2k. Basically, I'm using the triple disc TCC to simulate overdrive in 2,3, and 4.

Here are the questions ;)

1. I get some lugging when locking the TCC and have been fixing this as makes sense if you think about lugging from a manual tranny pov (e.g. I move the apply points up a few mph until the lugging goes away). The result is less lugging but higher shift points and higher rpms at steady state speeds. I'm okay with that if it increases the smoothness, but the real question is I've seen some dips to 12 afr at times when the tcc locks and rpms drop below ~1k. Is there some kind of protection mode that would kick in here? I just did an autove run yesterday, and this may be in a piece of the ve that doesn't get hit very often, but I don't want to be fighting the OS :)

2. When the tcc locks up it hits hard... Almost like a 2 washer shift kit. Is this a symptom of locking it up too soon (as the lugging is I assume)?

3. Would I be better off increasing the time in each gear, locking the TCC 3-5mph after the shift and letting it wind out a little with the TCC locked?

TIA

turboberserker
February 28th, 2006, 02:49 AM
Ok, I have the AFR changes in my sites... I noticed that locking up the tcc causes my MAP to jump (enough to hit 105kpa and be into my go fast AFRs). Also with the TCC locked, my MAP values are higher than in an unlocked state -- whereas unlocked is in the 50-75kpa range, locked is in the 80-100kpa range. I know the engine is under more load, but the increase in kpa seems disproportionate.

Are these increases in MAP as expected? If so, can someone explain