TT_Vert

iTrader: (12)

first thing I wanna do is get this thing to downshift w/less throttle effort. I dont want to go changing anything that will screw up other tables though. Im new the the auto side of HPT so please bare with me. I want this thing to shift hard at WOT but nice at part throttle and I would also love for it to downshift pretty much when i go WOT.
how bout torque management? Is there a trans tuning for newbs? Also, Im getting differing opinions about shift kits etc. Should i let computer deal w/ line pressure or what? Any free/cheap mods I can do to the 4l60E to make it a tad more duarable?

Thanks much

Dave

jimmyblue

iTrader: (11)

First you want to adjust the part throttle shift tables.
This is where your kickdown comes from. The stock
settings are pretty lousy for feel and refuse to kick
down except at WOT, leading to poor control. Try
one of my later tunes off Horist's site, for that.

The shift pressure line % vs load tables are for the
tapering of shift speed / firmness with load. You could
just set up the adaptation time values and let it learn
its way, but this leaves things prone to drift around
some and I lately prefer to zero the adaptation times
and just tweak shift pressures until the shifts get done
tolerably fast without being over-hard at lower pedal.
But I've also messed with the force motor tables a lot
so you probably don't want to be taking cues from my
tunes, in that respect; I'd say just tweak it up in an
incremental fashion, keeping an eye on the "time of
latest shift" PID and when it stops improving shift
speed, or just feels as hard at that pedal position as
you care for, leave off any more bumping. It will take
some time to get it all bedded in, helps to develop a
"test regimen" that will cover the envelope in a minimum
amount of driving (like country road, same series of 10%,
20%, ..., 100% TPS accelerations each time, should let
you seek to the goal fairly orderly and in short time).

For TM I recommend a couple of things. One, copy the
2-3 line to the 3-4 shift, which is unprotected in stock
tune. Just supposing you did shift the 3-4 under full
power someday. The other is, work over the spark retard
vs torque reduction table, which is where the amount of
spark retard comes from. You can see the delivered
torque - trans PID for the torque level preceding the shift
and follow that to the torque reduction vs torque table,
see the indexed torque cut. Now go to the retard table
and put some more sensible retard values in place of the
30-40 degrees you'll find. I use 10-15 and get about 40-60
lb-ft pulled back. Watch the delivered torque PID and up
the retard value a bit at a time until you see that it's
pulling a useful, but not sucky, amount of torque out.

At WOT you should see full line pressure anyway. But it's
worth a check.

As far as making the stock trans durable, I think the best
idea is a rainy day fund toward a fully beefed crate trans.
You can't just pick one weak link, the way GM designs it
there's a bunch of 'em (point of engineering being, to take
out any excess cost and weight until just shy of impacting
field returns). However, a large trans cooler and probably
a manual fan switch (or program fans to run low speed
below thermostat crackpoint and high speed not far above
that) for keeping it cool in the staging lanes is a must.

TT_Vert

iTrader: (12)

thanks man ill read this more thorougly when i get a chance. Really appreciate the input though
dave

VORTECFCAR

iTrader: (2)

Jimmyblue knows his stuff!

go through the 2-1 and 3-2 downshift table (tps vs speed vs shift point?) and futz with it, this alone makes a big difference!

also I would try Jimmyblue's force motor tables, they were a bit harsh down low for me, but a great starting spot. I'm trying for a sleeper drive at part throttle and tire blazing full throttle shifts.

ps - Lowering the Force motor voltage increases shift harshness