why is it bad to turn off TM?
TECH Enthusiast
Joined: Jan 2002
Posts: 531
Likes: 0
From: Helendale, Ca (SilverLakes)
Who said it was bad???
I had my full tune almost 2 years ago and my trans is fine.
All TM does is cut back the timing during shifts.
Mine shifts much better with the TM turned off.
I had my full tune almost 2 years ago and my trans is fine.
All TM does is cut back the timing during shifts.
Mine shifts much better with the TM turned off.
Here's the deal. You have a transmission that GM
rated for 600lb-ft of input shaft torque, and a lot
of people break them once they start modding the
motor.
Stock motor, 1.8:1 STR converter with 1900RPM stall
speed means you are holding the RPM down below
torque peak while the converter is multiplying. Maybe
200-250lb-ft, times 1.8 max multiplication, 450lb-ft
shaft torque, no problem.
Mildly improved motor and a mid-level converter,
maybe 3500RPM and 2.5:1 STR? Now you are up
on peak torque right where the converter is doing
its thing. 350lb-ft*2.5=875lb-ft shaft torque. As
an example.
Think GM rated the unit at 70% actual capacity,
or that you can run a mass production, cost-
engineered piece at 45% over rated torque for
long?
Torque management works off calculated trans
shaft torque. This is modeled based on the stock
converter, its 1900/1.8 character. Now, nobody
told the PCM when you put in the new converter
so when it sees 2000RPM worth of slip across
the converter at 4000RPM engine, it figures you
are making hella multiplication and engine torque,
so it calculates a huge torque reduction per the
tables and pulls out all the spark it can.
You could teach it some manners, or you could
just shoot it. But shooting the watchdog for barking
isn't going to help you in the long run. Using the
garden hose to educate it about when and how
loud, is more useful.
The more motor, converter and traction you have,
the bigger the rock and the harder the place your
transmission has to survive, between.
rated for 600lb-ft of input shaft torque, and a lot
of people break them once they start modding the
motor.
Stock motor, 1.8:1 STR converter with 1900RPM stall
speed means you are holding the RPM down below
torque peak while the converter is multiplying. Maybe
200-250lb-ft, times 1.8 max multiplication, 450lb-ft
shaft torque, no problem.
Mildly improved motor and a mid-level converter,
maybe 3500RPM and 2.5:1 STR? Now you are up
on peak torque right where the converter is doing
its thing. 350lb-ft*2.5=875lb-ft shaft torque. As
an example.
Think GM rated the unit at 70% actual capacity,
or that you can run a mass production, cost-
engineered piece at 45% over rated torque for
long?
Torque management works off calculated trans
shaft torque. This is modeled based on the stock
converter, its 1900/1.8 character. Now, nobody
told the PCM when you put in the new converter
so when it sees 2000RPM worth of slip across
the converter at 4000RPM engine, it figures you
are making hella multiplication and engine torque,
so it calculates a huge torque reduction per the
tables and pulls out all the spark it can.
You could teach it some manners, or you could
just shoot it. But shooting the watchdog for barking
isn't going to help you in the long run. Using the
garden hose to educate it about when and how
loud, is more useful.
The more motor, converter and traction you have,
the bigger the rock and the harder the place your
transmission has to survive, between.
11 Second Club
Joined: May 2004
Posts: 226
Likes: 0
From: Va. beach,Va
Originally Posted by jimmyblue
Here's the deal. You have a transmission that GM
rated for 600lb-ft of input shaft torque, and a lot
of people break them once they start modding the
motor.
Stock motor, 1.8:1 STR converter with 1900RPM stall
speed means you are holding the RPM down below
torque peak while the converter is multiplying. Maybe
200-250lb-ft, times 1.8 max multiplication, 450lb-ft
shaft torque, no problem.
Mildly improved motor and a mid-level converter,
maybe 3500RPM and 2.5:1 STR? Now you are up
on peak torque right where the converter is doing
its thing. 350lb-ft*2.5=875lb-ft shaft torque. As
an example.
Think GM rated the unit at 70% actual capacity,
or that you can run a mass production, cost-
engineered piece at 45% over rated torque for
long?
Torque management works off calculated trans
shaft torque. This is modeled based on the stock
converter, its 1900/1.8 character. Now, nobody
told the PCM when you put in the new converter
so when it sees 2000RPM worth of slip across
the converter at 4000RPM engine, it figures you
are making hella multiplication and engine torque,
so it calculates a huge torque reduction per the
tables and pulls out all the spark it can.
You could teach it some manners, or you could
just shoot it. But shooting the watchdog for barking
isn't going to help you in the long run. Using the
garden hose to educate it about when and how
loud, is more useful.
The more motor, converter and traction you have,
the bigger the rock and the harder the place your
transmission has to survive, between.
rated for 600lb-ft of input shaft torque, and a lot
of people break them once they start modding the
motor.
Stock motor, 1.8:1 STR converter with 1900RPM stall
speed means you are holding the RPM down below
torque peak while the converter is multiplying. Maybe
200-250lb-ft, times 1.8 max multiplication, 450lb-ft
shaft torque, no problem.
Mildly improved motor and a mid-level converter,
maybe 3500RPM and 2.5:1 STR? Now you are up
on peak torque right where the converter is doing
its thing. 350lb-ft*2.5=875lb-ft shaft torque. As
an example.
Think GM rated the unit at 70% actual capacity,
or that you can run a mass production, cost-
engineered piece at 45% over rated torque for
long?
Torque management works off calculated trans
shaft torque. This is modeled based on the stock
converter, its 1900/1.8 character. Now, nobody
told the PCM when you put in the new converter
so when it sees 2000RPM worth of slip across
the converter at 4000RPM engine, it figures you
are making hella multiplication and engine torque,
so it calculates a huge torque reduction per the
tables and pulls out all the spark it can.
You could teach it some manners, or you could
just shoot it. But shooting the watchdog for barking
isn't going to help you in the long run. Using the
garden hose to educate it about when and how
loud, is more useful.
The more motor, converter and traction you have,
the bigger the rock and the harder the place your
transmission has to survive, between.
to follow.......
