16197427 and a 700R4 ?

[EagleMark]

Just wondering if a 16197427 ECM is capable of handling the controls for a 700R4? I know they will do the newer 4L60E and 4L80E and I have even seen a manual transmission bin for them but not seen one for the 700R4...

[Six_Shooter]

Yes they will, there is a certain selection of bits that needs to be set and a couple values changed. The XDF that was made by 93V8S10 has the needed changes in the description of the tranny related items. I believe this XDF is available for download on the Tuner Pro site. If not it is posted in a long thread that talks about $0D on the Full Size Chevy forums.

[JeepsAndGuns]

Bringing this thread back up.
Does anyone have any more details on exactly what needs to be done to make the 7427 work right with a 700r4?

Long story short, I have a coworker I have been doing a little tuning to his 92 1500 with a 350. His stock ecm is a 16146299. I looked over his truck and harness and it appeared to be the same as a 7747 system. So We plugged in one of my eeprom modded 7747's and it runs perfectly fine, everything works just the same. I started with a 88 350 auto bin and have done some tweeking of the timing table and a couple datalogs to keep an eye on ping. He says it has made a night and day diffrence in how it runs, how much power it has, and even its fuel mileage. He says he has owned it since 93 and it has never had that much power. He said his fuel mileage went up from about 12-13 up to about 16-17. (he is a older man, and doesnt drive like us lead foots...lol, but likes power when he needs it)
Seeing how much of a diffrence a 7427 made to my jeep, we are both really curious if it would make any diffrence to his truck. I have a 350 bin file I read from a memcal I can start with, if I can make it work with his 700r4.

[dave w]

Here is information I think I got from either TGO or FSC.

dave w

[1project2many]

I believe I posted a .bin or at least the BCC for a factory 700R4 cal for the 7427. Maybe it was even BJYL. I'll look around.

[JeepsAndGuns]

Wow, interesting. The stock 350 bin I have is that BJYL. I read it straight from the memcal. Its the stock bcc that was in the 7427 I am running. It was also the one I was gonna start with.
So that bin is alreaday set up for a 700r4?

[1project2many]

Confirming...

The BJYL 350 tbi 700R4 cal that is attached above appears to be set up for 700R4. Stock BJYL is not set up for the 700R4.

[dave w]

The BJYL should have parameters similar to these.

dave w

http://i239.photobucket.com/albums/ff290/buildabot2002/FSC/Davids700R4Programming-02.jpg

[dave w]

These parameters need to be configured.

dave w



http://i239.photobucket.com/albums/ff290/buildabot2002/FSC/TCCSettings02.jpg

http://i239.photobucket.com/albums/ff290/buildabot2002/FSC/TCCSettings.jpg

[JeepsAndGuns]

In these pictures above, has that BJYL 700r4 bin already had these changes made, or do I need to go in and make those changes?
I should be able to find all those scalers and change them to whats pictured above. But that hex box scares me! I would not have the slightest clue about doing that. I would most definately mess something up there!

I have not had a chance to look over the above bin and defination yet.

[dave w]

Here are a couple pictures I hope helps with the hex.

http://i239.photobucket.com/albums/ff290/buildabot2002/FSC/ManualTransmission.jpg

http://i239.photobucket.com/albums/ff290/buildabot2002/FSC/TorqueConverterClucthOnly.jpg

dave w

[JeepsAndGuns]

I remember checking that manual trans flag and setting that table to zero for the bin I am running in my jeep.
On this 700r4, do I need to check both of those boxes, or only the "tcc only" flag. And if I change that table to zero, do I still need to do something in that hex?

[dave w]

I remember checking that manual trans flag and setting that table to zero for the bin I am running in my jeep.
On this 700r4, do I need to check both of those boxes, or only the "tcc only" flag. And if I change that table to zero, do I still need to do something in that hex?

I honestly can't answer the questions above and say the 700R4 will work. I'm still working on making the one '427 / 700R4 conversion I've done work! Here is the tread I have going at FSC:

http://www.fullsizechevy.com/forum/general-discussion/performance/tbi-tuning-87-95-obd-i-ecm-pcm/472950-427-pcm-upgrade-700r4.html

I think I've dotted all the "i"s and crossed all the "t"s and my '427 / 700R4 conversion is not working.

dave w

[EagleMark]

Just a theory! But your taking a PCM designed for 4l60e and running a 700r4 hack, then turning things off for 4l60e so something may be interrupting the VSS speed to transmission or something is not set correctly for VSS speed to transmission? I did not follow closely enough to see what/how/why you are using for the TCC. You say switch for TCC is on? But no lockup?

Why am I bringing this up? Because I had the same issue in a $EE LT1 with 4l60e and no Torque Converter Lockup. Trans shifted fine, speedometer worked fine. In the $EE XDF was three scalers for VSS. I don't see any equivent in $OD. The one I ignored because it was listed as "Speedometer Scaler (scan tool)" was exactly what the transmission was seeing. I only found this when driving around with Scan Tool hooked up watching data of trans. TCC switch came on! No lockup! Looked at transmission speed in scan tool and it was 18 MPH (not enough for TCC lockup) and speedometer on car was 40 MPH. I think I felt it lock up at 80 MPH on car, but hard to tell at that speed. When I fixed this scaler, the vehicle speed and transmission speed were the same and TCC worked. So in this case even though TCC switch was on, there was no lockup. HTH!

[JeepsAndGuns]

So, after all this time, has anyone had a confirmed successful attempt at running a 700R4 with a 7427?
Me and my co-worked are still curious to try a 7427 swap, but I'm not gonna waste my time hooking up my adapter harness and starting on a bin for his truck if I can not get the tcc to work as it should. Auto trans parameters are over my head (I'm a manual trans guy myself...lol)
So hoping by now someone may have gotten it to work and would be kind enough to share the bin file.

[shane300zx]

Im interested in this also. I have an upcoming project that was a 60e and now going 700r4

[pmkls1]

So, after all this time, has anyone had a confirmed successful attempt at running a 700R4 with a 7427?
Me and my co-worked are still curious to try a 7427 swap, but I'm not gonna waste my time hooking up my adapter harness and starting on a bin for his truck if I can not get the tcc to work as it should. Auto trans parameters are over my head (I'm a manual trans guy myself...lol)
So hoping by now someone may have gotten it to work and would be kind enough to share the bin file.

This thread is a little old, so I'm not sure what changes have been made to the xdf and adx files since this thread was started, but yes I have been running this setup for over 6 months and 10k miles now. The latest xdf and adx files available here and on the tunerpro site for v5 have all of the parameters and the flag to properly operate the tcc function on a 700r4. The xdf has some great tips that help to set up your bin properly. I'll upload my latest bin and one I found on this site for reference. An important warning on my bin is that I have the parameters set so that the tcc will not unlock when you let off the gas to coast and that's why I'm loading the other bin which can also be found on this site which is basically a stock BJYL bin that someone has modified to work with a 700r4. I'll go ahead and upload the xdf and adx file that I use as well. My adx is modified to enable the maptrace function, but that is easy to change and the only change I have made. Everything is fairly easy and straight forward IMHO. You can basically enable the tcc only function by checking the flag and then modify the paramaters after driving to suit driver preference. For safety purposes I recommend making an additional wiring change different from the conversion schematics found on this site. Pin number E13 on the 7427 PCM is a brake switch input that most people will use the wire from pin C16 on the 747 ECM as it supplies a constant +12v when running. I prefer to go ahead and run a switched brake input to terminal E13 when using the 7427 PCM so that the PCM sees the brake switch input. This doesn't really affect anything for this conversion as the brake switch interrupts power to the tcc anyway. But, if a 4l60e is swapped in later and wired in properly the TCC solenoid will stay energized because the power does not run through the brake switch. HTH,
Phil

[JeepsAndGuns]

Cool, I will have to check out that bin. What bin did you start with, so I can do a compare and see what all you have changed.
Since my co-workers truck is 100% stock, I will simply use a stock 350 bin and change the needed 700r4 parameters.

[pmkls1]

Cool, I will have to check out that bin. What bin did you start with, so I can do a compare and see what all you have changed.
Since my co-workers truck is 100% stock, I will simply use a stock 350 bin and change the needed 700r4 parameters.

I started with a BJYL bin. The BJYL 700r4 bin that I uploaded is just a copy of what somebody else uploaded to the site in the ecm info section. My bin is extensively modified because I am running an L31 engine with the tbi unit on top of a 4bbl intake. The details of my setup are listed in my sig. The combination of the engine I have and the high fuel pressure I run required the extent of modification to the original bin image I began with. So in other words, don't pay attention to any of the parameters outside of the tcc operation. The BJYL 700r4 bin, on the other hand, is almost a "plug-n-play" bin for a stock L05 in an older truck since it was used on an L05 engine to begin with. My bin would still make a good comparison bin as I have modified the tcc parameters to suit my personal preferences and it is pretty different from stock. Somthing to keep in mind, though, is that I have a Firebird which is going to be able to handle more of a load before requiring the tcc to unlock because it is a much lighter vehicle. This is important to remember because you can damage the converter or the 3/4 clutch pack by placing too much load on the vehicle with the tcc applied. But don't let me scare you with all this info because it is very simple to make everything work properly.

[JeepsAndGuns]

Having the tcc perform exactly as it did stock with a 7747 would be perfectly fine. He's not a gearhead like us (even though he is a mechanic) He doesnt drive wild like us youg lead feet...lol. But he does want it to go when he wants it to. I did a little work to a 7747 bin and put it in his truck and he said the difference was night and day. I remember talking to him about my 7427 swap and how much better my engine ran after the swap, so that made us curious to try it on his. I just wasnt sure if we could get it working with the tcc. We definately want to keep that feature.

[pmkls1]

Having the tcc perform exactly as it did stock with a 7747 would be perfectly fine. He's not a gearhead like us (even though he is a mechanic) He doesnt drive wild like us youg lead feet...lol. But he does want it to go when he wants it to. I did a little work to a 7747 bin and put it in his truck and he said the difference was night and day. I remember talking to him about my 7427 swap and how much better my engine ran after the swap, so that made us curious to try it on his. I just wasnt sure if we could get it working with the tcc. We definately want to keep that feature.

Honestly, if you start with the BJYL 700r4 bin you will probably only have to make some minor tweaks and you'll have a finished tune. The tcc parameters for a 700r4 in the $0D mask are different than a 746 or 747 ecm so it will probably take a couple test drives to get the lock and unlock thresholds right because they are going to vary depending on vehicle weight and gearing. Having converted a vehicle originally equipped with a 746 ecm to the 427, I am confident that he will be amazed with the difference though. Good luck, and let us know how it goes,

Phil

[JeepsAndGuns]

I am running a manual trans, so I never looked into it with my swap. But when using a 7427 with the 700r4, where do you hook the park/neautral switch to the 7427? Seems I have read somewhere on here it was one of the "range" inputs, but I dont know witch one.

[pmkls1]

The P/N wire should be orange with a black stripe and located at pin B10 on the 747 ECM. That wire goes to terminal E5 on the 427 PCM. The 747 ECM also has a wire for the 4th gear switch that the 427 PCM does not use so you'll just have to tape it up or something to that effect. Just an FYI, the 700r4 will only lock up in gears 2-4 regardless of wether the TCC solenoid is energized or not. The only reason that the ECMs originally used with 700's used the 4th gear switch was to use a different load map and mph thresholds for 4th gear TCC control versus gears 2 & 3. There really isn't a need for so many TCC parameters. The load-based TCC parameters in the xdf for the $OD mask are simplified and use a 2D table that uses TPS% and vehicle speed. The older ECMs used 3D tables based on engine load and vehicle speed. Anyhow, I'm overcomplicating a simple question now lol. Here's a link to the thread that covered the swap for your reference http://www.gearhead-efi.com/Fuel-Injection/showthread.php?173-7747-RIP-ECM-to-427-PCM-Swap-with-Wiring-Pinout-Directions!&highlight=16197427 . But I'll still gladly answer any questions you have as I had a few myself that weren't answered in the thread.

[dave w]

Usually, for the '427 PCM, pin E5 is used for an automatic transmission (4L60E / 4L80E) will be used for Trans Range C input. I find it very interesting the old '7747 P/N switch is wired to E5. It's my understanding that the '7747 P/N switch is sending ground to the ECM when the P/N switch is in either park or neutral position. I wonder what Trans Range C input (ground when in park / neutral) is telling the 4L60E/4L80E? Does Range C at ground disable TCC?

dave w

[pmkls1]

Usually, for the '427 PCM, pin E5 is used for an automatic transmission (4L60E / 4L80E) will be used for Trans Range C input. I find it very interesting the old '7747 P/N switch is wired to E5. It's my understanding that the '7747 P/N switch is sending ground to the ECM when the P/N switch is in either park or neutral position. I wonder what Trans Range C input (ground when in park / neutral) is telling the 4L60E/4L80E? Does Range C at ground disable TCC?

dave w

That's an interesting question Dave. I think that you may be looking at things the wrong way if I understand your question correctly. The range switches simply tell the PCM what range you have selected on the shifter. There are only 3 range switches (A B C) but the PCM can determine what range is selected out of 7 different possible positions (P R N D 3 2 1). This is done by the switch grounding the 3 signal circuits in a specific combination (on on off, on off on, etc....) much like the way that it only requires 2 shift solenoids to obtain 4 differend forward gears. It just so happens that out of coincidence you only have to ground the range C input for the PCM to think that the gear selector is in park or neutral. These inputs were solely for the PCM for shifting purposes and the typical lower rev limiter etc..... As far as the transmission part of the equation, a combination of the manual shift valve and solenoid inputs "tell" the transmission what to do. In all but the newer style of electronic transmissions GM makes, there is still a lot of mechanical control of the transmission and the electronic portions are adapted to the mechanical design. Even though certain transmissions like the 4L80E, 4T80E, & 4T40/45E lines never had a full mechanical predecessor like the 4L60E did, they are still designed much like a "typical" mechanically operated transmission with electronic components "adapted" to the design. This is why they all still have relatively large and complex valve bodies. The newer designs like the 6L50/80/90E and the 6T70E have much smaller and simpler valve bodies and extremely small solenoid packs/TCM assemblies. Although it was a horrible transmission, the Chrysler A604/41TE utilized this concept in 1989. The actual reason those things were such a disaster wasn't due to the design principle of the shift control mechanism, but due to crappy components and the requirement of a special trans fluid with specifically engineered friction modifiers that mos people didn't use. As a matter of fact it's a little off topic, but I've got a PT Cruiser down by the basement with a burned up tranny that's most likely due to improper fluid being used. I know it was a bit of a long rant, but did that address your question ? lol :laugh:

[JeepsAndGuns]

B10 to E5, thats what I needed to know. I knew I had read the answer somewhere on here, but could not find where and couldnt remember it.

[pmkls1]

B10 to E5, thats what I needed to know. I knew I had read the answer somewhere on here, but could not find where and couldnt remember it.

Well, if you wanna just cut to the chase and skip over all of the unnecessary ramblings, then that's your answer lol. I just thought you might wanna spend your saturday afternoon sorting through a bunch of irrelevant info lol j/k :laugh:

[JeepsAndGuns]

Nothing wrong with it, the extra info is helpfull.
I too have been accused of "ask him the time and he will tell you how to build a watch"

[EagleMark]

There is also an XDF for this but the zip folder was corrupt, it is now fixed in the $0D info thread. And attactched.

[Six_Shooter]

Just to get technical, the 3 inputs (A, B, C) could provide up to 8 states of input. It's just that one state isn't used in this application. ;)

[pmkls1]

There is also an XDF for this but the zip folder was corrupt, it is now fixed in the $0D info thread. And attactched.

I had tried to download that a while back when preparing for my PCM swap and couldn't because it was still corrupt. The advanced $OD TP5 V250 xdf has tables in it as well for TCC only control as well and that is the only xdf I have used up until this point. I downloaded the xdf you linked there just to take a peek and noticed that it actually has some separate TCC tables for low gears and high gear. That caught my attention because of what I had said earlier about it not being necessary to have separate tables and that there wasn't a pin location shown for the 4th gear switch input when swapping in a 427 PCM in place of a 746 or 747 ECM. Now I'm curious to go look at my car and see if I found where to plug in the 4th gear switch input or not. It has been long enough that I don't remember that part of the swap. And I haven't looked through all the schematics since the swap either as I haven't needed to. Since the xdf I have been using doesn't have separate tables, I wouldn't take notice of anything in the adx when logging that would indicate if the PCM detected it was in high gear or not. If I didn't find where to connect the 4th gear switch input then I am curious about where it goes. This is all really not very important as the PCM and tranny will function perfectly without the use of the 4th gear switch, but it piques my curiosities nonetheless.

[EagleMark]

I was just looking at the BJYL 700R4 bin... do you guys who are running this realize it's not a stock BJYL timing table? Actually a very well built table, but lots of advance over stock!

It's got more changed then just timing. FYI.

[JeepsAndGuns]

Yea I was curious last night and compared it to the stock bin. I too found the different timing table, it does appear to be a nice looking table. Knowing nothing about stock chevy engines and what timing they like, would it be a good table for a 100% stock 92 5.7 tbi engine running regular unledded?
Other items I noticed was ccp was turned off, I can understand that.
Cat over temp protection was turned ON. What is this and what all does it actually do? Is it needed on a stock 92 350 engine?
Naturally, the tcc only flag was checked.
PE spark was set to all zero, I'm guessing this was because of the changed timing table?
And then noticed the speed and rpm limits were raised.
There might be more, I cant remember, I dont have TP open right now and I am on my way to work.

[pmkls1]

Because I am running a vortec engine, I forgot about looking at the timing tables as vortes heads like a way different ignition curve than the old swirl port TBI heads. I had done the same thing with PE advance by simply adding the timing into the regular table and zeroing out the PE table. Cat over temp protection isn't necessary on a '92 truck or any vehicle with a decent tune for that matter. You asked what it does so be prepared for a long ramble again lol.

I'm not 100% sure exactly how it works as I have never had any issues that would cause the cats to overheat on my personal vehicles (because they don't have any, shhhhhhhh) or as a technician. I have seen cats that have been overheated, but it happened some time before I began repairing the vehicle. But, I believe that the PCM uses a certain algorithm to calculate if certain conditions would cause the cats to overheat. I know for sure that it will make adjustments to timing and fuel and emissions functions to allow the cats to cool down. The main reason for all of that crap is because catalytic converters are more efficient at higher temps. So the engineers will program the PCM to operate the engine and emissions equipment in a manner that will heat up the cats faster and keep them hot. Things like less timing, leaner mixtures, and AIR injection are what heat up cats. The issue is that under heavy load situations the catalytic converters can easily get too hot and literally melt down.

The reason it isn't necessary for "us" is because most of the things we do to tune an engine for better driveability and performance will actually cause the cats to run cooler. I too forget what all is different in that bin and will have to wait until later to take a good look at things like the spark tables again. In general, I remember that most of the changes made were all things I would do. I'll take a look later when I have a chance and let you know what I think about the spark tables and any other suggestions. I appologize for suggesting a bin that had that much changed, but I forgot that it had that many changes.

[RobertISaar]

not sure about 0D and similar, but with the 60V6 stuff, if cat overheat is detected(calculated), timing is advanced and AFR is richened considerably.

[dave w]

Here's a screen shot of an aggressive timing table, 5.7 liter using TBI swirl port heads / L31 Vortec roller camshaft / stock compression ratio / ported TBI intake to accept 7.4 Throttle Body / shorty headers / 3" single exhaust / 3" catalytic converter / Cop Car Injectors / 87 octane E10.

dave w

http://i239.photobucket.com/albums/ff290/buildabot2002/TBI TEST BENCH/E6Timing.jpg

[pmkls1]

not sure about 0D and similar, but with the 60V6 stuff, if cat overheat is detected(calculated), timing is advanced and AFR is richened considerably.

I believe that is generally the way cat overheat protection works on just about any of the GM stuff out there. There is only so much you can do with programming to cool down the cats on a running vehicle. Just taking a peek at some of the tables it appears that is about the extent of it. Like I said, I'm not that familiar with the cat overheat protection stuff in PCM's, but it appears to operate using about the same principle that an EBTCM does to avoid overheating the brakes. The rotor temps are calculated by a complex algorithm programmed into the EBTCM. If rotor overheating is detected (calculated) then the ABS and TCS functions are limited until they have been given enough time to cool (calculated). That's why I don't feel it is necessary to utilize the cat overheat protection on a well tuned vehicle. Because more than likely the possibility of overheating the cat(s) is going to be reduced due to the tendency of most people to add a little timing and fatten up the fuel delivery.

As far as the differences between the stock BJYL bin and the BJYL 350 700r4 they were only the differences earlier. The spark tables are pretty aggressive and I'm not sure how well those would work with a completely stock L05 running regular grade gas. There's a good possibility that they would work ok, but they seem to be pretty close to the limit of what you could get away with. I might recommend sticking with the stock ignition tables and maybe gradually adding some timing since you say the guy isn't a gearhead like all of us. If it weren't for the fact that he doesn't seem to be that interested in making more power then I'd say try those tables and back off the timing as needed. But since you're not trying to make this thing into a big project I recommend comparing the stock BJYL spark tables to his stock tables and see how close they are. Since the BJYL bin should still be for an L05, the spark tables should be fairly close. What I was really getting at when I suggested starting with the BJYL 350 700r4 bin was that you could use all of the TCC parameters as a good starting point.

I'd say the easiest thing to do would be to start with the stock BJYL bin and copy over the TCC tables and any other changes you think your friend may want from the other bin. That will be fast, easy, and get you up and going without ending up going crosseyed from an information overload. All of the bins you need for comparison can be found in the 427 PCM thread in the ECM part # info section here on the site.

[EagleMark]

:yikes:

Before anyone goes and grabs these timing tables. Don't! They may not be right for your mask. Even if they are right for your mask there could be differant Spark Bias. Neither of them is for a heavy vehicle and forget it towing. BJYL and the spark table dave w posted are 2 differant heads. There's more, just don't.

Learn how to build your own spark table in your bin and mask from stock bin.

[JeepsAndGuns]

I'd say the easiest thing to do would be to start with the stock BJYL bin and copy over the TCC tables and any other changes you think your friend may want from the other bin. That will be fast, easy, and get you up and going without ending up going crosseyed from an information overload. All of the bins you need for comparison can be found in the 427 PCM thread in the ECM part # info section here on the site.

Thats the thing, I compared it to a stock BJYL bin (that I personally read from a memcal) and all the tcc parameters are the same. Only differences are the above mentioned ones. ccp turned off, cat over temp turned on, tcc only checked, timing tables, pe spark zeroed, and rpm/speed raised.

The guy is not a gearhead, but he wanted more power. He said ever since he has had that truck, it has never been as powerfull as he thought it should be. I did some logging a tweeking of a stock 7747 bin and timing table and it made a world of difference in his truck. I may pull up the timing table I built for that bin and compare it to the table in the 700r4 bin and and a stock 0D table and go from there.

[pmkls1]

Yeah, I had another derrrr moment there as I missed the obvious there. I ran the compare function in TP and derrrrr the TCC parameters were the same because I verified all of the differences were mentioned. Personally, I would turn the CCP on and the cat over temp off. Removing the speed limiter is fine, but I would set the rev limiter to about 5k rpm's as a stock L05 TBI engine is gonna run out of steam long before that point anyways. I don't have the rev limit set much higher on my car just because it isn't making any power up there. It's kind of pointless to rev them any higher than the peak power point anyway on a regular street vehicle. If the guy would like more power then I would try to emulate the timing table that you already established in the old ECM. As far as using the PE spark tables goes, I personally prefer to just add the spark into the main table and zero out the PE table just to keep things simple. But, for the most part a stock bin like the BJYL should be a good starting point since there are not very many differences mechanically between the two trucks. The main differences were the ECM/PCM's and the transmissions, and the transmissions are nearly the same other than the electronic controls.

[JeepsAndGuns]

Yea I reset the speed and rpm limiters back to stock. He would never come close to them anyways...lol

[JeepsAndGuns]

Failure!
Well, not completely. We finally jumped in today and gave it a try. I brought everything to work with me today to give it a try. I hooked it up with my adapter harness and engine starts and runs good. He says its noticeably smoother running. We also found out yesterday that a parts store must have given him the wrong knock sensor a few years ago because its a 3.9k ohm sensor like used on the 7427 trucks and not the 100k ohm sensor like is supposed to be on there. Odd thing, is it has never popped up any check engine lights for knock sensor or circuit over the past years. Odd, as I would think having the wrong knock sensor would trigger a trouble code? So we just had to unplug the stock est and install the jumper wire I made, since it already has the later KS.
But anyways, no tcc lockup. We tried the 700r4 bin with no luck. So I tried a stock bjyl bin, and made the approaite changes and tried it, no luck there either. We ran out of time to play more.
So I have come home tonight and have copied all the tcc parameters from pmkls1's bin he posted up and we will try that tomorrow. If no luck there, anyone have any other suggestions?

[EagleMark]

Verify MPH to be accurate in data log. VSS pulse is differant on 7747 ECM (2kPPM) to 7427 PCM (40kPPM) as is VSSB/DRAC. If MPH qualifiers are not met then no TCC.

Paremeter RPM/VSS ratio.

[pmkls1]

I didn't have any issues with getting the speed to be correct in the PCM after my swap. You said that you used your harness adapters to install the 427, do the adapters run the orange wire from pin C16 on the 747 to pin E13 on the 427 ? And did you alter the TCC brake switch wiring any ? If you simply switched over the wires like in the conversion thread the TCC brake input on the 427 gets ignition voltage and the TCC will funcion. I know that I recommended performing some rewiring to the system just because I preferred to wire the vehicle like the original 427 schematic. But, if you just used the adapter harness that you built then I would double check that there is ignition voltage on pin E13 at the 427 PCM. If all is well there then I would double check that the TCC solenoid power circuit still has power although it is unlikely that it would be due to a blown fuse as the TCC circuit runs off of the ecm ign fuse. Other than that, there is another flag that should NOT be checked. It is under the 4L60E transmission parameters in the flag section labeled "output speed not from DRAC". That box needs to stay unchecked. The stock BJYL bin and mine don't have them checked anyway, but it is something else to look at. I did not alter the RPM/VSS ratio parameter at all and the speed shown in the PCM matches my speedo exactly. Also, which pin on the 427 did you wire the TCC signal to ? One would think that it should go to pin E10 as that is the 4L60E TCC control pin but it actually needs to go to pin E11 which is the PWM TCC control. I never checked into why and just wired it as the schematics said to, but I know that it works that way so I left it alone. Hopefully you will find your issue somewhere in there without having to look elsewhere.

[JeepsAndGuns]

I can verify that the speed was reading correctly. And yes, I do have the box checked for "output speed not from drac" I checked that because on my conversion, I did not get speedo to display in the adx untill I did so. I will uncheck it today and see if it still displays correct speed. Also, yes, I have the tc wire on pin E10, witch was labeled as tcc. I didnt hook it to the pwm tcc wire as I figured it wouldnt work on there since this thing doesnt have a pwm tcc. I will swap the wires after trying the output seppd flag.
You said I should be applying power to pin E13, brake signal? Wouldnt applying power to that signal that the brakes are on? I did not alter the factory wiring on the truck any.

[pmkls1]

I can verify that the speed was reading correctly. And yes, I do have the box checked for "output speed not from drac" I checked that because on my conversion, I did not get speedo to display in the adx untill I did so. I will uncheck it today and see if it still displays correct speed. Also, yes, I have the tc wire on pin E10, witch was labeled as tcc. I didnt hook it to the pwm tcc wire as I figured it wouldnt work on there since this thing doesnt have a pwm tcc. I will swap the wires after trying the output seppd flag.
You said I should be applying power to pin E13, brake signal? Wouldnt applying power to that signal that the brakes are on? I did not alter the factory wiring on the truck any.

I believe that because vehicles like his truck and my car have a VSS buffer, they have the same output pulses as a DRAC so they will work properly without any other alterations. I used pin E11 instead of E10 because that is what the conversion chart specified. I would have assumed the same as you that since the solenoid is not a PWM solenoid that it would go to pin E10. I never investigated why that pin was used because it worked properly and I just left it alone. I suspect that it may have something to do with the code when altering it for TCC only functions causing the hardware to utilize that circuit.

As far as applying ignition + to pin E13 goes, it is because vehicles equipped with the 427 and a 4L60E/4L80E are wired completely different than a vehicle equipped with a 700R4 and a 747/746/730 etc..... That is what I spoke of in one of my earlier replies. Vehicles equipped with a 700R4 had the TCC solenoid energized through an ign + wire that was interrupted by the brake switch. The brake switches in most all GM vehicles from around the '70's up until recent years had 2 sections, 1 section closed a circuit when the pedal was depressed which was for the brake lamps. The second section opened a circuit when the brake pedal was depressed and this was for the TCC and Cruise Control. The ECM had no brake switch input and thus did not use brake pedal status as a part of the equation for applying or releasing the TCC. The ECM simply grounded the TCC solenoid to control it. The PCM's designed to operate electronically shifted transmissions did use a brake pedal input which was pin E13 on the 427. This is because the electronic trannys like a 4L60/80E have 2 (IIRC) ignition + wires going to them to power all of the solenoids. Since the TCC solenoid now had a constant ignition + source that was not interrupted by the brake switch they simply moved the brake switch interrupted ign+ signal over to the PCM as a monitored input. This way they could still use the same brake switch that fit nearly every vehicle they made and also not alter much on the cruise control wiring either. The PCM still simply grounded the TCC solenoid as well as all of the additional solenoids used for shifting and pressure control. They now had a brake input so when the signal to pin E13 was interrupted the PCM interpreted this as the brakes being applied and removed the ground to the solenoid.

Now, the reason that most people just transfer over one of the ign+ wires used on the 747 to the 427 brake input is because it doesn't need the extra ign+ circuit and you can leave the rest of the wiring alone as the brake switch will still interrupt the + side of the TCC solenoid. I had suggested rewiring the brake signal to go the PCM and then running a constant ign+ to the TCC so as to emulate the way that the 427 is wired but it is totally unnecessary and irrelevant to your issue.

[JeepsAndGuns]

So when the 7427 get power to pin E13, it thinks the brakes are not on, and no power to that pin it thinks you are putting on the brakes?

I tried changing the speed signal not from drac back, made no difference, but like you said, speed on the datalog dash still read, and read correctly. We then tried swapping the tcc wires, E10 to E11. Still no dice. We unfourtnately ran out of time again, as he needed to go home after lunch. Also, I had forgotten about it, he is off work untill the first of the year. He's is having total knee replacement surgery. So we hooked the old ecm back up and we will pick this project back up when hes back on his feet.

If the brake input is wired like above, that may be the problem. I will add the wire to my adapter harness and we will give it another go in a couple months.
Question, is that brake input used only for tcc operation? In my 7427 conversion in my manual trans jeep, I have nothing hooked to that pin, would adding the wire change anything?

[EagleMark]

So when the 7427 get power to pin E13, it thinks the brakes are not on, and no power to that pin it thinks you are putting on the brakes?Not sure on the 7427 pins but yes, that is correct. Power on brake off, power off brake on. On the 7747 the TCC solinoid has power all the time and when TCC is commanded the ECM sets the ground. If you hit the brakes the power is removed and TCC unlocks, it will not engage TCC again untill TPS position is increased past idle with brake not applied of course. Hope that helps you get 7427 wired right.

http://www.gearhead-efi.com/Fuel-Injection/attachment.php?attachmentid=1937&d=1331599707

[pmkls1]

Yes, you are correct. The PCM gets ignition switched voltage to pin E13 that runs through the brake switch. Applying voltage = no brake apply; No voltage = brakes applied. The brake switch interrupts the signal by opening the circuit when you apply the brakes. That circuit is separate from the brake lamp circuit in the stitch and there are separate connectors on the brake switch. The brake switch input is only for TCC operation and technically shouldn't affect anything on a manual trans vehicle. After you add the wire to that pin you should get TCC operation I'm quite sure.

The only reason I ever mentioned rewiring the brake switch earlier is because the PCM will see when the brakes are applied and you can see this in data logs. Because I had mentioned rewiring the brake switch I wanted to know if you had made any wiring changes that could have possibly affected the TCC operation.

[pmkls1]

After seeing the schematic Mark posted I remembered a nifty little trick that you can do that helps when diagnosing TCC issues on 700 R4 and 200 4R equipped vehicles. You can ground terminal F of the ALDL connector and manually control the TCC solenoid. If the wiring and TCC solenoid are good then you will have lock-up regardless of the ECM command state. You can ground that terminal with the shifter in any position and the vehicle moving or stationary. Because of the mechanical workings inside the trans, the TCC solenoid can be energized, but the pressurized fluid will only make it to the converter apply piston in gears 2, 3, & 4. That is a very quick way to test TCC operation on a vehicle to aid in diagnostics. It also can lower ET's at the drag strip especially on vehicles with a looser converter. Just a little FYI

[RobertISaar]

apparently the grand national guys have used that trick for a while, lowers their ETs by close to half a second IIRC.

kills the TCC eventually, but it is an interesting result.

[pmkls1]

apparently the grand national guys have used that trick for a while, lowers their ETs by close to half a second IIRC.

kills the TCC eventually, but it is an interesting result.

That is where I picked the trick up a long time ago. Using it for those purposes will shorten the life of a lot of components in the trans. But typically if you're down to trying to pick up a few more tenths of a second at the strip you're not worrying about longevity anymore. Back about 15 years ago I used a toggle switch on an '87 Trans Am of mine to retain the TCC function after I had replaced the computer controlled carb and dizzy for a Carter AFB and an old big cap HEI. It worked for a very long time before something finally crapped out on me. I never got around to diagnosing the issue because not too long after that the engine had a little explosion and lightly charred the front of the car. That failure was actually caused by a hanging float on a Holley carb that I had installed later. That wasn't the only time that I had an issue with a Holley doing the exact same thing. So nowadays I'm a little jaded and am biased toward Edelbrock carbs which are just a re-branded carter AFB.

[EagleMark]

I was at a trans shop this week and they had a TCC cutaway. After seeing how little clutch it had I think I'll be releasing lockup at lower MAP to disengage under load...

[RobertISaar]

keep in mind different converters have vastly different sized clutches.

i'd LIKE to have a converter that would hold up to a good 400 ft-lb of load..... could basically lock it as soon as hitting 2nd gear and keep it locked at pretty much all times above that.

[JeepsAndGuns]

Its stock, so we dont want to do anything that will cause damage to the tcc or trans. I will add the power wire to the brake pin on my harness and we will give it a try when he gets back on his feet.
We both thank all of yall for all your help through this.

[pmkls1]

Its stock, so we dont want to do anything that will cause damage to the tcc or trans. I will add the power wire to the brake pin on my harness and we will give it a try when he gets back on his feet.
We both thank all of yall for all your help through this.

You don't need to worry about doing any of that other stuff, it was just a little FYI for anyone watching the thread. I'm confident that once you get power to pin E13 you will have TCC operation again. Be sure that once you verify that you can get TCC operation that you go back to the TCC parameters in the stock BJYL bin because the ones in mine are modified a lot. And you are quite welcome. I'm happy to help any time that I can.


I was at a trans shop this week and they had a TCC cutaway. After seeing how little clutch it had I think I'll be releasing lockup at lower MAP to disengage under load...

As long as you're fairly close to stock on the load parameters you're fine. Although it is easy to burn up the clutch linings in most O.E. style converters, most converter failures are due to constant cycling and too much slip allowed in units with PWM controls. I actually recently began having issues with a bad shudder in 4th gear lockup after the load passes a certain point. I had raised the load thresholds some because I was getting too much cycling activity when cruising and evidently I went too far. At this point I haven't determined wether it is the converter or the 3-4 clutch pack because it could be either one. But the end result is the same, the converter needs replaced and the trans rebuilt. I'm not very heartbroken though because I've been wanting to swap in a 4L60E for a long time now.


keep in mind different converters have vastly different sized clutches.

i'd LIKE to have a converter that would hold up to a good 400 ft-lb of load..... could basically lock it as soon as hitting 2nd gear and keep it locked at pretty much all times above that.

For the most part at least in GM applications the stock converter clutches are usually pretty dinky. You can raise the holding capacity a little by adding apply pressure, but the other downside of most stock converters is that the clutch apply plate flexes too easily so you end up back at square one. You can get some pretty wild converters for a lot of different transmissions if you have the $$$$ to throw down.

[JeepsAndGuns]

You don't need to worry about doing any of that other stuff, it was just a little FYI for anyone watching the thread. I'm confident that once you get power to pin E13 you will have TCC operation again. Be sure that once you verify that you can get TCC operation that you go back to the TCC parameters in the stock BJYL bin because the ones in mine are modified a lot. And you are quite welcome. I'm happy to help any time that I can.

We ran out of time before I tried the bin with your parameters in it, so I will stay with the stock BJYL bin parameters when I try it again.

[pmkls1]

We ran out of time before I tried the bin with your parameters in it, so I will stay with the stock BJYL bin parameters when I try it again.

I would definitely recommend that because he would definitely think you screwed his truck up if you ran the parameters from my bin lol.