'89 R3500 Crew Cab 2wd to 4wd conversion & beyond

[Tnsejed]

I think that would work but wouldn’t you have to swap tunes along with shifting the tcase?

Yeah he would. Which seriously sucks. Same with his original plan of changing gear ratios to match his low side final ratio. I was commenting more on his worry about TCC lockup between ranges, and it appears he can adjust the TCC tables in two tunes and get it to work. Or do a ratio change.

Really to figure it out he has to figure out what 'manual mode' means. Does holley want people to check this if they have a full manual valve body. Or is it something else. If its something else then are you able to use the TCC lockup tables in this mode? If its manual gear changes, and can use a TCC table, can you wire a switch to change to this mode or do you have to reflash.



Another option I saw was sport mode in the tuning. I would assume you can switch this on the fly somehow. If you could make sport mode be manual gear shifts, using a separate TCC table, you'd have it I think. With only one switch when moving to low side. If it can't use a seperate TCC table then just wire a manual TCC switch for whenever he's in low range and needs to cool the tranny. After that get a bigger cooler.

 

[folkenheath]

Manual mode means it will be in whatever gear you put the shifter in, it won't shift automatically.

His original plan was to just put it in manual mode for low range and shift it manually.

He could load a new tune, but that takes time and you have to key off and it wouldn't be worth it unless you planned to stay in low range for quite a while. It would be very easy to make a duplicate tune and just multiply the axle ratio by the trans ratio and put that in for the axle ratio to trick the ECU.

The best solution with the Holley is to have the VSS in the trans before the Tcase, then it works just like a TH350, TH400, or 700R4 as none of them know if there is a Tcase behind them or what range it is in, they just do the same thing no matter what based on the transmission output shaft RPM. The only thing is things happen faster in low range, so it may need a little tune tweaking to work in low range WOT, but once that is done, it will work just fine in high range too.

If you do that you can put the VSS for the speedo in the Tcase so it's always right, or use a GPS speedo, or a speedo with a math multiplier you can switch in the dash.

 

[mrk5]

I have played around with the trans tuning in the software but @Tnsejed is right I'm gonna have to test it out and see how it works "in the field".

Manual mode in the old controller would allow the TCC to lock up much easier. I'm not sure after this many years if that was something I did in the software or not. I may have been able to change TCC characteristics in manual mode on that controller. The Terminator does allow TCC in 2nd thru 4th so that's good. The old 454 sometimes needed to pull mountain passes in 2nd gear, especially towing the camper, so it was good to be able to lock the converter to keep the trans temps down. Maybe the new motor will be able to do it in 3rd gear anyway.

The Terminator version 3 software will allow 2 different shift parameters for a 6L family of transmission, but for whatever reason it's not able to with the 4L transmissions. It would be nice if Holley could make that happen.

My thought was the second tune for low range would not only have the different gear ratios but I'd also lower the minimum thresholds for the TCC engagement. One thing I've always liked about the big block is that it can handle the load of the TCC at lower RPMs. It will lug it out going slow on the trail at low RPM.

I am curious how the logistics would work swapping out tunes for the trail. We already sit for a while at the start and beginning of trails, airing up/down, loading/unloading gear, etc. Once I'm in low range I tend to stay there. The only change is usually whether or not the 205 is in low, the Magnum is pretty much always in low. The problem I can see is if we're running between trails when we normally wouldn't need to stop for anything. Some people I wheel with haul balls down the dirts tracks between trails....

It's definitely going to be a learning curve. I'm sure it will take some trial and error too. Either way I figure I need to have a laptop with me for the first few, maybe several, runs so I can make some tweaks.

I am losing some capabilities from the old trans controller but the Terminator is allowing me to get rid of a bunch of wiring and other items. I have some empty holes to plug in the firewall now.

I'm just starting to figure out the software, and it should give me plenty to play and experiment with. I did get it setup to run the transmission cooler fan so I'm stoked about figuring that out.

 

[Tnsejed]

You should also check if swapping tunes will reset the fuel learn and trims. That would be a bummer if there is no Fast Write while keeping all learned trim tables.

Any luck on the 'sport mode' or if it has 'tow haul' mode. I saw it in the holley video on a 4l80e, but who knows if that is still correct. If so can that be programmed to have the different parameters needed? Maybe that's the shift parameter you were talking about though.

FWIW swapping tunes seems like the worst option of everything.

 

[mrk5]

I should be able to save to the laptop whatever the current tune is before uploading the other tune. So each time it will have the most up to date tables.

Hopefully the manual mode will do everything I want.

 

[Tnsejed]

In factory gm the fuel learn is stored in the ecm. This is different than your Primary VE tables. So you have the tables you have programmed in the tune, and then the ecm will populate its own tables with learned fuel trims. For example, Airflow model table at 45kpa and 2k rpm = X , where X is your primary VE. This X is your 'tuned' number. The one you told it. The pcm looks to that but stores its measured fuel trim (learned trim) from long term and short term trims, transients, historical data, etc. These are the learned trims. This stuff is all needed as driving is rarely ever steady state.

If writing a new tune deletes this learned data that would suck. I found in the terminator X manual that "it is advised to limit learning to 10% or less after self learning". I also read there is an option to "Transfer learn to base map". That tells me it is working similiar to a factory system. So long as you remember to transfer that learned data I think you'll be good.

 

[mrk5]

At this point my biggest concern is the TCC engagement. I don't mind the manual shifting mode, I kinda like it really and it's how I tend to drive on the trail anyway. So maybe I would just need to tweak the TCC tables for the trail. I think I would need to drop the TCC Lock/Unlock speeds WAY down.

I've done a little looking for info on manual TCC activation in the 4l80 but I haven't had any luck. Most of the forum threads I've found devolve into a discussion on how the person should be okay with the factory operation of the TCC, etc.

 

[folkenheath]

At this point my biggest concern is the TCC engagement. I don't mind the manual shifting mode, I kinda like it really and it's how I tend to drive on the trail anyway. So maybe I would just need to tweak the TCC tables for the trail. I think I would need to drop the TCC Lock/Unlock speeds WAY down.

I've done a little looking for info on manual TCC activation in the 4l80 but I haven't had any luck. Most of the forum threads I've found devolve into a discussion on how the person should be okay with the factory operation of the TCC, etc.

You can lock the TCC manually just by switching it to ground, either by a separate switch in parallel or a virtual switch in the dash if you have an extra output. I do that with a virtual switch myself in the Regal but I rarely use it.

In factory gm the fuel learn is stored in the ecm. This is different than your Primary VE tables. So you have the tables you have programmed in the tune, and then the ecm will populate its own tables with learned fuel trims. For example, Airflow model table at 45kpa and 2k rpm = X , where X is your primary VE. This X is your 'tuned' number. The one you told it. The pcm looks to that but stores its measured fuel trim (learned trim) from long term and short term trims, transients, historical data, etc. These are the learned trims. This stuff is all needed as driving is rarely ever steady state.

If writing a new tune deletes this learned data that would suck. I found in the terminator X manual that "it is advised to limit learning to 10% or less after self learning". I also read there is an option to "Transfer learn to base map". That tells me it is working similiar to a factory system. So long as you remember to transfer that learned data I think you'll be good.

It has a learn table and a base table. The learn table can be combined with the main table, cleared, or left alone as a separate table. When all tuning is complete, the learn table should be shut off and then it should just rely on closed loop correction. Leaving learning on indefinitely is not a good idea because if something goes wrong it could learn from incorrect data and actually make it much worse.

The software is free to download from Holley if you want to play with it, I have been using The Holley software for 7 years now, it's some of the most powerful and capable software on the market, but like everything, it has it's pros and cons.

 

[mrk5]

You can lock the TCC manually just by switching it to ground, either by a separate switch in parallel or a virtual switch in the dash if you have an extra output. I do that with a virtual switch myself in the Regal but I rarely use it.

So I just need to identify the correct pin on the plug into the transmission that activates the TCC, correct? Then I can tap into that wire with a switch to ground?

 

[folkenheath]

So I just need to identify the correct pin on the plug into the transmission that activates the TCC, correct? Then I can tap into that wire with a switch to ground?

Yes, you can use my manual wiring diagram to see it, its also in the resources here on CK5.

4L80Ewiring | Volcano Manifolds

www.volcanomanifolds.com

It should be noted that the hydraulic circuit in the trans won't allow lockup in 1st gear.

 

[mrk5]

 

[folkenheath]

Sounds good, nice deep rumble.

How did it drive?

 

[mrk5]

It feels like it has more pep! I drove pretty cautiously. As I was driving, I was thinking okay, what did I forget to tighten down? Oh year, the front spring bolts are just finger tight and the front clip is barely bolted on! I did get 1 or 2 shifts out of the transmission so it seems to be working.

Nate was commenting about the exhaust having a different tone and I told him I figure it's because of the higher compression.

I really need to take some time and get the digital dash hooked up to the terminator so I can see what's going on. I'll have to redo the gauges so they're reading from the can connection. With the Sniper a few of the gauges were standalone. Plus I'll need to add some transmission info.

Yes, you can use my manual wiring diagram to see it, its also in the resources here on CK5.

4L80Ewiring | Volcano Manifolds

www.volcanomanifolds.com

It should be noted that the hydraulic circuit in the trans won't allow lockup in 1st gear.

Do you think the Terminator will freak out if I manually lock the TCC? I was reading about factory setups throwing codes when you do a manual switch.

 

[folkenheath]

Yeah I wouldn't be comfortable driving it if I can't see the oil pressure and temp, etc.

Compression and camshaft profile can both change the way an engine sounds, even if it's the same base engine with the same cubes and firing order.

The Terminator will not freak out, I've done it, I've locked it using a virtual switch in the digital dash that grounds that same wire with another output, though I have the Dominator, they run off nearly the same software. It will just continue to do what it is supposed to do based on the pressure, shift, and TCC tables, etc. With a switch the lockup will be immediate, no ramp on or off, but you'll find it's not harsh.

I have a triple disc lockup, and when I spray nitrous at the track, I lock it up at 135 MPH under WOT with nitrous on, and it feels like another shift. I used to do it manually but now, when in race mode, with the nitrous armed, the computer does it for me. However, don't use lockup above ~50% throttle without a triple disc converter.

 

[mrk5]

For anyone interested, I found the wiring diagram for Holley's 4l80e (and other models) harness. That way I know which wire color is the TCC.

The original is too large to upload so here's a link to it:

https://images.holley.com/558-4051957.jpg

 

[mrk5]

Yeah I wouldn't be comfortable driving it if I can't see the oil pressure and temp, etc.

Compression and camshaft profile can both change the way an engine sounds, even if it's the same base engine with the same cubes and firing order.

The Terminator will not freak out, I've done it, I've locked it using a virtual switch in the digital dash that grounds that same wire with another output, though I have the Dominator, they run off nearly the same software. It will just continue to do what it is supposed to do based on the pressure, shift, and TCC tables, etc. With a switch the lockup will be immediate, no ramp on or off, but you'll find it's not harsh at all.

I have a triple disc lockup, and when I spray nitrous at the track, I lock it up at 135 MPH under WOT with nitrous on, and it feels like another shift. I used to do it manually but now, when in race mode, with the nitrous armed, the computer does it for me. However, don't use lockup above ~50% throttle without a triple disc converter.

As much as I like using the TCC, this makes me want a triple disc converter.

 

[mrk5]

Small things sometimes take the most work. I busted out the tube bender to make a new tie-bar between the shock hoops. First attempt went in the tuition pile but I figured that was going to happen re-familiarizing myself using the bender.



I welded 3/8" thick plates to the top of the shock tabs with match plates on the crossbar. Should have made the plates a little longer, but they'll get the job done.

Also mocked in the air intake. I'll make a bracket off the core support to hold the filter behind the headlight area.



I do plan to cut down the inner fenders and reinstall them. I think seeing the engine thru the fenders is cool, but I don't want mud and other junk thrown all over the engine.

 

[kgblazerfive]

You would be better at just building another set of inner fenders.

 

[mrk5]

When I decided to narrow the front, I thought I might have to ditch my giant radiator. I was worried the smaller radiator might have trouble keeping the engine cool so I made plans to move the trans cooler to the bed.

I figured I would need to step up my cooler game so I found a really good price on a Derale Hi-Flow Racing remote cooler; a seller on ebay had it for $150 less than Summit.



It's 95,000 btu versus the 29,200 btu I did have.

I mounted it below the spare tire.





When I was installing it I dinged the fins in a couple spots so that made me hyper-aware that I may want to add some protection. I was picturing someone pulling the spare off and dropping a wrench on the cooler. In regards to the install dings, in the future I would put cardboard over it while working.

The spare does pretty much obscure it.

 

[Babaganoosh]

What fluid you running through that cooler? thats a big dog!