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Old 06-08-2004, 01:05 AM
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Default 1-2 Late Shift

My 1-2 shift started shifting later once I upped the boost. 6#

With EDIT, I brought down the shifts from 6300 to 6000. Sometimes it will shift close to it. Most of the times it will hit my rev limiter @ 6800.

Before FI on a 150 shot, shifts were set @ 6300 with no issues.

Any ideas?
Old 06-08-2004, 08:18 AM
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Don't remember whether you have minimized the
adaptation time settings or not. You are probably
needing the trans to cycle quicker to keep up now.
If you're at minimum on settings then the next
question is, is it keeping up (<0.1 sec to take care
of business) or not (and, how much time does it
take for the engine to run up from 6000 to 6800
now anyway?).

On your 150 shot did you spray through the
shift, or cut spray before (so runup through
the shiftpoint was in fact no faster than stock)?
Old 06-08-2004, 09:59 AM
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I will check the settings. It doesn't take very long at all to go from 6000 to 6800. If it was a stick, and I shifted @ 6000 I would always hit the limiter.

You are right, I stopped spraying before the shifts so it would shift fine on N20. :doh:

Now it makes more sense. Thanks!
Old 06-08-2004, 03:49 PM
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I don't see that setting in EDIT?
Old 06-08-2004, 07:24 PM
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By adding more & more horsepower, you are more than likely "pulling through" the shift. This will reqiure modifications to the feed holes on the valve body plate, & changing to a larger boost valve, at a minimum. The "modified" Trans-Go Performance Shift kit will address this. As 60 foot times start to come down, this can cause the oil pickup to become uncovered and create the same problem as described above. Overfilling the pan (a small amount, 1/2 -3/4 quart) will stop this. I have seen both several times over the years.
Old 06-08-2004, 07:36 PM
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Have not hit it from a stop. No traction. But when it did over-rev, it was from a 10 mph roll and a 30 mph. I thought my tranny could handle all the power.

What do you mean by modified trans-go? I have one.
Old 06-08-2004, 09:44 PM
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Shift Adaptation Time? I think this is your
"Desired Shift Time" sub-table, I see it in
the LS1-Edit manual on the Transmission
Calibration menu (check manual pg 20-21).
I would set it to a nonzero value, I currently
run w/ 0.150. Zeroing it gives full pressure
through the shifts, need it or not, and this
makes the WOT 1-2 unmanageable even
without boost. You know, you might want
to look at this as an "opportunity" to use
the engine torque management to deliberately
"mellow out" 1st gear and the 1-2 shift since
you have more than you can hook up. There
is (at least in my HPTuners) quite a bit to play
with. Like max torque vs RPM vs gear, you
could use to hold it down to (say) 400lb-ft
until you get her into 2nd. Whatever stays
one RCH short of continuous wheelspin. Just
a thought.




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