"Built" Transmission Tuning...

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05-06-2012
Turbojunky

"Built" Transmission Tuning...

I have a 2004 Silverado with a turbocharged forged 6.0L.

The transmission is a 4l65 with a pro-torque 3500 converter, redline clutches, shift kit, billet servos, deep pan and probably some other stuff.

My question is what needs to change in the transmission tuning to accommodate the modifications? I have heard people are turning the line pressure up as well as the TCC duty cycle. Sorry I'm a newb when it comes to this whole auto trans thing.

Any help/suggestions would be greatly appreciated. I can provide any info you might need as well.

Current tune attached...
05-06-2012
jimmyblue

The "built" trans is probably more durable, but may not
want anything special. Depends on whether the builder
increased mechanical line pressure, went to vacuum
modulated (probably not helpful on a forced induction
setup unless positive pressure is "comprehended" by
the modulator).

The converter, that wants the usual converter stuff.

Now I think I'd be playing a lot with line pressure and
give it all-in, early just for luck. Do not know what your
vehicle has for General Pressure stuff, or if you just
want to jack the force motor table around to get what
you want.

I'd begin with some scanning and look for signs of slip
in the frictions, going by input/output shaft speed ratio
against the nominal in-gear ratio. This is the sign you
need more steady state pressure, and it's likely to be
worst at light / cruise where GM went for economny
and bet you wouldn't mod up.

There're some how-tos out there that are pretty
reasonable, though they may have less to say about
more extreme setups (like turbo).
05-06-2012
Turbojunky

Thanks for the info. How much of a difference do you typically see between the input and output shafts as far as RPM? I would assume you don't want to see any difference at all right?

I know that the base line pressure was turned up but I'm not sure how much. How do I scan line pressure? I found a PID for Force Motor (PCS) Line Pressure but that was the only line pressure I saw.

Thanks again for the help!
05-06-2012
edcmat-l1

Quote:

Originally Posted by Turbojunky

Thanks for the info. How much of a difference do you typically see between the input and output shafts as far as RPM? I would assume you don't want to see any difference at all right?

I know that the base line pressure was turned up but I'm not sure how much. How do I scan line pressure? I found a PID for Force Motor (PCS) Line Pressure but that was the only line pressure I saw.

Thanks again for the help!

The input and output shaft speed difference will depend on what gear it's in.

I don't think there are any pressure pids for that trans. Pretty sure there isn't.
05-07-2012
midevil1

FYI...no such thing as a BUILT 60E, 65E, and 70E. Anemic piles of crap. Keep at least 50% TQ management..
05-07-2012
Turbojunky

Quote:

Originally Posted by edcmat-l1

The input and output shaft speed difference will depend on what gear it's in.

I don't think there are any pressure pids for that trans. Pretty sure there isn't.

What is the best way to determine my gear ratios? The trans is not the original out of my truck and I don't know where it came from.....
05-07-2012
Shrek

Quote:

Originally Posted by Turbojunky

What is the best way to determine my gear ratios? The trans is not the original out of my truck and I don't know where it came from.....

All 700R4 / 4L60 / 4L60E / 4L65E / 4L70E have the same OEM gear ratios.
05-07-2012
Turbojunky

Quote:

Originally Posted by Shrek

All 700R4 / 4L60 / 4L60E / 4L65E / 4L70E have the same OEM gear ratios.

Thanks, again I am a total newb when it comes to transmission stuff.

I took a good log today of a bunch of different driving. I have attached the log along with the config file I am using. Also attached the current tune again. I am curious what is going on right at 4:32. Its during a hard second gear pull. The input rpm shoots up but the output stays steady. That would be considered a "slip" right? Could this be something with the converter?
05-07-2012
midevil1

Quote:

Originally Posted by Turbojunky

Thanks, again I am a total newb when it comes to transmission stuff.

I took a good log today of a bunch of different driving. I have attached the log along with the config file I am using. Also attached the current tune again. I am curious what is going on right at 4:32. Its during a hard second gear pull. The input rpm shoots up but the output stays steady. That would be considered a "slip" right? Could this be something with the converter?

You answered your own question. You are seeing the converter flash.
05-07-2012
edcmat-l1

Quote:

Originally Posted by midevil1

You answered your own question. You are seeing the converter flash.

No, the converter flash should be engine RPM versus input shaft RPM. When it flashes, there's a rapid rise in engine RPM, but not input shaft RPM. The converter's out shell and impeller increases RPM rapidly with the engine RPM, the turbine and input shaft lags behind.

The point in the data log which he's asking about kinda concerns me. It's well into the RPM range, and when he goes full throttle, the converter doesn't really flash, because of the fact that he's so far into the RPMs. There is about a 1000 RPM flash (little less maybe) when he goes from part throttle to full throttle. You can see that in the top chart. But, the spike in input shaft speed happens a little later. To me, that looks like a clutch pack slip.

Edit: You can see the converter flash between frames 1304 to 1310. Look at the RPM rise, before it flattens back out. That's the flash.
05-07-2012
Turbojunky

Quote:

Originally Posted by edcmat-l1

No, the converter flash should be engine RPM versus input shaft RPM. When it flashes, there's be a rapid rise in engine RPM, but not input shaft RPM. The converter's out shell and impeller increases RPM rapidly with the engine RPM, the turbine and input shaft lags behind.

The point in the data log which he's asking about kinda concerns me. It's well into the RPM range, and when he goes full throttle, the converter doesn't really flash, because of the fact that he's so far into the RPMs. There is about a 1000 RPM flash (little less maybe) when he goes from part throttle to full throttle. You can see that in the top chart. But, the spike in input shaft speed happens a little later. To me, that looks like a clutch pack slip.

Edit: You can see the converter flash between frames 1304 to 1310. Look at the RPM rise, before it flattens back out. That's the flash.

Thanks for the info. Any suggestions? Is there anything I can change in the tune to help this?
05-08-2012
midevil1

Quote:

Originally Posted by edcmat-l1

No, the converter flash should be engine RPM versus input shaft RPM. When it flashes, there's be a rapid rise in engine RPM, but not input shaft RPM. The converter's out shell and impeller increases RPM rapidly with the engine RPM, the turbine and input shaft lags behind.

The point in the data log which he's asking about kinda concerns me. It's well into the RPM range, and when he goes full throttle, the converter doesn't really flash, because of the fact that he's so far into the RPMs. There is about a 1000 RPM flash (little less maybe) when he goes from part throttle to full throttle. You can see that in the top chart. But, the spike in input shaft speed happens a little later. To me, that looks like a clutch pack slip.

Edit: You can see the converter flash between frames 1304 to 1310. Look at the RPM rise, before it flattens back out. That's the flash.

Hell, I didn't even look at the log. My bad.. Time for an 80E and never look back..
05-08-2012
midevil1

Quote:

Originally Posted by Turbojunky

Thanks for the info. Any suggestions? Is there anything I can change in the tune to help this?

Take your shift times down to .100 in all gears in performance. at least .175 in normal. Quick shifts and some TQM will help a lot, but the 60E's are not a transmission that will handle the power with the weight of a truck. NEVER gonna happen.
05-12-2012
Turbojunky

My Force Motor Current table is still stock. Should I lower those numbers to achieve a higher pressure?
05-18-2012
01ssreda4

Read Cool-Aids write up. It's pretty helpful explaining all the tables and what they do. I know its posted on LS1tech and may be posted here too.
05-25-2012
IJ.

Quote:

Originally Posted by 01ssreda4

Read Cool-Aids write up. It's pretty helpful explaining all the tables and what they do. I know its posted on LS1tech and may be posted here too.

It's posted here as well.