Tuning a crate 350 H.O.

[rokcrawlin85]

I'm currently working on tuning my 85 K5 Blazer using a retro fit TBI off a 91 Suburban with 350/th400 setup for my 350 H.O. I am using the 1228747 (HD truck) ECM using $4F and tunerpro rt for tuning. I'm having issues keeping it from stalling out when going from park to gear. i would love some help with some things to look at in the bin other areas. I would also like to add a A/C idle raise somehow to the bin to raise my idle while using a winch or the on board air, but i have no idea how to add definitions. Help with this would be awesome too. Is it possible to use the $42 mask since its used for the 7747, which, as far as i can tell from reading, are very close to the same?

[EagleMark]

There's a guy here doing a 1227747 conversion to his 1228747 system but not sure what he did or is doing to control the Turbo 400 kickdown. Naybe he has updated the details? The ECM plugged in. The $42 XDF and ADX files are more detailed because of all the work into them. May be able to find some more paremeters from $4F hac to add to XDF?

Stalling from Park to Drive? Conversion system... did you hook up Park. Neutral wire and VSS? These are 2 things that work the IAC logic to make that a smooth transition. Mine never even has a hint of a hiccup there...

Since you have a 350 HO motor getting a good solid idle would be first. I'm guessing you can tune/burn a chip? With that motor adding 100 RPM to Idle, may be 2 spots for Opena and closed loop would help. Adding a few degrees at distributor timing with wire disconected would help but must take that extra and add it to Intail Timing setting which is usually 0 on these trucks, so if distributor set to 2 or 4, set Intail timing to 2 or 4. This takes it off top so you don't end up with to much timing!

Then doing the Min Air Setting because of the change in engine at link below is a real help for stable idle.
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?581-Initial-Setup-of-TBI-TPI-and-MPFI-systems.-Min-Air-Adjust-TPS-set-and-Fuel-Pressure

[rokcrawlin85]

i know i'm fighting some issues with tuning at low RPM's. i do not have VVS since i am running the 700R4 from the 85 K5 (no electronics). as far as i remember i have raised my target idle to around the 750 mark to keep it from trying to hop around at idle. I was debating on starting fresh again with one of the stock bins from the 1228747 forum for a 7.4 since my motor obviously needs more fuel than a stock 350 would. bad idea? It's nice to have choices. i haven't found that many stock bins for this ecm before!!

I would love to have more peremeters to change like you can do with the 7747 mask. can you post up a link to that thread about converting to the 7747? How do you use the hac info for the $4F to change what the ecm reads? i haven't a clue about that... too deep to explain?

[EagleMark]

Here's the link to guy doing the swap already.
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?571-1228747-to-1227477-swap

You can add a VSS to speedometer cable with aftermarket from Jaqs that run, or in your case a speedometer cluster from newer 1987 truck or 1987 to 1991 Blzer or four door dually, Suburban as they has a VSS in speedometer, to DRAC, to ECM and ABS, cruise control.

Starting with 7.4L bin just to add fuel is not going to add fuel, just change VE table closer to 7.4L VE.

Problem with adding fuel to 1227747 and I'd need to look at 8747 is there are VE1 and VE 2 adder tables. If you add the 2 together your already over 100% and it is supposed to truntacate back to 100 so GM made a mistake from factory. Tuners don't like to go over 95 as a rule as injectors can go static (never close, flicker, spase out) Really only way to get more fuel for more HP engine is adjustable regulater and rasie pressure. Only way to get it right for your motor is do data log and tune your VE tables.

Hacs and adding things to XDF is not something I am that knowledgable of, others guys here are and we will see what they say. I have not even opened the $4F hac to see what it has to say, maybe take a look and see what you can find?

[rokcrawlin85]

In the $4F mask it only has one VE table. Probably due to the fact most of the trucks using these ECM's aren't going to be pushing higher RPM's, since there mainly used for towing and what not. I have been playing with logging and changing VE stats. I'll jsut keep playin and seeing what works for the better and post up with what i find or with questions.

[EagleMark]

I've only been answering your questions, but someone is going to come along and suggest you do a ECM swap to 16197427 since it is about a bizillion times faster and has a bizillion times more paremeters and hac options $OD is best supported... electric fan options, MPFI options...
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?173-1227747-to-16197427-Conversion-PCM-Swap-with-Wiring-Pinout-Directions

Repin your wires to 16197427 PCM
Remove ESC and run knock sensor wire to PCM
Have to have VSS, actually VSS is a good thing on all EFI systems whether you can remove them and run or not. You can fool even a fool! But why take out something that works?

I think Greg has a couple for sale with plugs and pin tails in for sale section if you don't have a Pull and Save JY nearby...

G1 Adpater and 27S512 chip from Moates with a burner, TunerPro and all other files needed are here! :happy:

[JeepsAndGuns]

Yep, I'll be the one to suggest the 7427 swap. :innocent2::happy:


I would love to have more peremeters to change

I have the answer for you. Its called the 16197427 PCM. Simply change the wires from your old connectors, and put them in the connectors for it (using a wiring diagram of corse), and have a computer thats 100 times better. Learing curve is a little steeper, but if I can do it, anyone can. I have loved this computer ever since I have swapped it in.

[gregs78cam]

Does anyone know how closely the '7747 and the '8747 are built to each other? I mean do they have the same MCU I/O ports. My bottom line thought is, would it be possible to run $42.bin in this ecm, and tweak it with $42.xdf and log it with $42.adx? You know just like we can run $0D, $0E, $85, $E6 interchangeably in '7060, '8625, '6395, and '7427.

[EagleMark]

The 1227747 and 1228747 came in same years trucks. 7747 has 700R4, 8747 has Turbo 400. ALDL is identical except one byte word change.

If he is willing he could do it. If I had one I would try. Just stick a $42 bin in and record data with $42 adx, or $4F adx only one thing is differant...

Only issue I know is TCC error code or what controls turbo 400 kickdown. Other guy was saying kick down wored on stock $42 chip but did not on one I sent with TCC turned off... so as myth busters say "Plasuble"

[rokcrawlin85]

Does anyone know how closely the '7747 and the '8747 are built to each other? I mean do they have the same MCU I/O ports. My bottom line thought is, would it be possible to run $42.bin in this ecm, and tweak it with $42.xdf and log it with $42.adx? You know just like we can run $0D, $0E, $85, $E6 interchangeably in '7060, '8625, '6395, and '7427.

So to do this just keep the 8747 ECM with no changes to it and just swap from using the 8747 bin and definition file to 7747 and run it with the $42 mask? If the only difference is tranny control... just switch the flags and other setting in the bin to just disable it... would that not work? just like i have done to disable EGR and Knock sensor... just change the perimeters high and low to keep it from kicking in

[EagleMark]

That's what we were doing in the other thread but guy was moving and had to stop.

You seem knowledgeable enough! Just burn a $42 bin on chip and slip it in and give it a try? I think he said turbo 400 kickdown worked, but then when I gave him a bin with TCC disabled it did not. So that might be what works the kickdown? I just don't know how the kickdown works or have wiring or have ever seen one so it would be a test? Sounded like he almost had it... read post above about it, we had a few wire differences figured out.

[rokcrawlin85]

well i'll give it a shot when i have a chance and burn a stock truck (7747) bin to a chip and stick it in, and see what happens. i'll post back with results as soon as im able to get to work on it. Is there any changes that need to be made to the start and stop locations for the 7747 chip compared to a 8747 chip?

[EagleMark]

Same chip 2732a and same bin file 4k. Same offsets if using Moates 27S512 stuff.

[rokcrawlin85]

Yep, that's the stuff im using. sounds too easy to be true, but we'll find out for sure after i get it plugged in. Mark, would your suburban tune, you have in the link thread above, be a better start for an initial check?

[EagleMark]

Works good on my truck! :thumbsup:

But my motor is stock. That bin also had Highway Lean Cruise enabled as well as PE changes, would have to disable both to get good BLM readings for VE fuel adjustments. Your VE table on $4F is quite differant so if it's tuned for your motor it would not import well... you could spend some time to get specific RPM MAP cells correct, midway the missing. Or 0 out VE2 and use just VE1, I've never done that but IIRC there needs to be a value in first cell?

I beleive in that thread I zipped it with a modified XDF file so changes I made to 3-4 things to disable TCC were noted. XDF paremeter name has ******** after it. These were changes I know worked on turbo 350 trans. But I think one was what did Turbo 400 kickdown because he said it didn't work anymore. So that part is up to you to figure out?

Like I said we had a lot of it figured out, Jim even found the couple wire differences that were atributed to TCC lock up.

Maybe while your doing this you can explain how the Turbo 400 Kick Down works? Or is wired? Or if you have scanned wiring diagrams for 1228747 I will add them to the 1228747 ECM information thread as we don't have them yet.

[rokcrawlin85]

i willl certainly give as much info as i can. I have limited knowledge with in depth tuning. Also, the kickdown and TCC just need to be disabled completely in my application due to the fact im just running a 700R4 with a TV cable, no electronics needed to tune the tranny charicteristics.

i think ill give your tune a shot with PE and Lean disabled. my VE tables are not truely dialed in on my chip now. i would like to go off a known good base timing table that's not too much timing since i have no knock sensor and vortec heads. If all goes well ill start with tuning the VE tables only and see if everything else falls in line after those are closer to what my motor wants. tune it one thing at a time.

I love this site!!! Great job this this site guys! I love that everything on here is legit, truly used bins and defs by others and everyone's helping others out. Nice work!

[EagleMark]

I love this site!!! Great job this this site guys! I love that everything on here is legit, truly used bins and defs by others and everyone's helping others out. Nice work!That's what it was for! Learn and share! No limits to cetain vehicle, no rules on topics, just open conversation! Glad your here helping and testing.


i willl certainly give as much info as i can. I have limited knowledge with in depth tuning. Also, the kickdown and TCC just need to be disabled completely in my application due to the fact im just running a 700R4 with a TV cable, no electronics needed to tune the tranny charicteristics.

i think ill give your tune a shot with PE and Lean disabled. my VE tables are not truely dialed in on my chip now. i would like to go off a known good base timing table that's not too much timing since i have no knock sensor and vortec heads. If all goes well ill start with tuning the VE tables only and see if everything else falls in line after those are closer to what my motor wants. tune it one thing at a time.
Oh! I thought you had turbo 400? That was the other guy with 1228747 system from factory.

So your 700R4 runs with no TCC? $42 does TCC...

[PJG1173]

i would like to go off a known good base timing table that's not too much timing since i have no knock sensor and vortec heads.

I've looked all over the internet trying to find a good base vortec timing table for a tbi. I have read that a vortec tbi was offered from the factory in mexico but have yet to see a bin for it. There also seems to be a lot of debate at different forums on what vortec heads call for in reguards to timing in a tbi application. really comes down to cam, compression, fuel, ect. I can tell you when I put vortec heads on my 4.3 the stock tables were useless and it was a gutless wonder. I copied the timing table out of a efi live tune file and still had to bump it up across the board before the engine would come alive.

[rokcrawlin85]

Your correct, no TCC. So in the $42 def, i can just change the setting to keep if from trying to kick in and change the flag setting correct? Basically, long explaination short, take any settings in the $42 def that i do not have, and change them so they don't set an error code or try to kick in with my peticular setup.

[rokcrawlin85]

I've looked all over the internet trying to find a good base vortec timing table for a tbi. I have read that a vortec tbi was offered from the factory in mexico but have yet to see a bin for it. There also seems to be a lot of debate at different forums on what vortec heads call for in reguards to timing in a tbi application. really comes down to cam, compression, fuel, ect. I can tell you when I put vortec heads on my 4.3 the stock tables were useless and it was a gutless wonder. I copied the timing table out of a efi live tune file and still had to bump it up across the board before the engine would come alive.

that's good info to know! i thought the vortec/fastburn heads required less overall timing due them being more efficient than the older style heads. at least from what i've read over at thirdgen. I was reading about the issue with the IAC seeming to keep the idle high when you come off the throttle, (i feel i have the same issue) maybe we're trying to push too much timing in the lower RPM cells?? If this 7747 burn will work for me, ill be looking more into the IAC variables, since it has much more options than the 8747 ECM offers for control.... But i won't be able to even get started on that until the weekend at the earliest.

[EagleMark]

I've looked all over the internet trying to find a good base vortec timing table for a tbi. I have read that a vortec tbi was offered from the factory in mexico but have yet to see a bin for it. There also seems to be a lot of debate at different forums on what vortec heads call for in reguards to timing in a tbi application. really comes down to cam, compression, fuel, ect. I can tell you when I put vortec heads on my 4.3 the stock tables were useless and it was a gutless wonder. I copied the timing table out of a efi live tune file and still had to bump it up across the board before the engine would come alive.Somewhere here we have a Vortec TBI bin file!


Your correct, no TCC. So in the $42 def, i can just change the setting to keep if from trying to kick in and change the flag setting correct? Basically, long explaination short, take any settings in the $42 def that i do not have, and change them so they don't set an error code or try to kick in with my peticular setup.Yup! Actually it was already done and marked in XDF from other thread.

[rokcrawlin85]

Awesome!! when i get home ill be loading that one up and taking a look at it. Mark, if you find that stock vortec TBI timing bin post it up here for the sake of anyone running the 350 H.O. since they are vortec heads, and for my sake to maybe splice it into the the timing table on your 7747 bin and see how it works.

[PJG1173]

This might help "16197427=96-97 export truck vortec head tbi\63\Brdw.bin"

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?408-fuel-curves-for-7747-running-stock-vortec-shortblock&p=2902&viewfull=1#post2902

[EagleMark]

Awesome!! when i get home ill be loading that one up and taking a look at it. Mark, if you find that stock vortec TBI timing bin post it up here for the sake of anyone running the 350 H.O. since they are vortec heads, and for my sake to maybe splice it into the the timing table on your 7747 bin and see how it works.Mark likes to help and do this kind of stuff specially in winter! But a little overwhelmed with life this afternoon... just found out my wifes brothers son (nephew) ended his life at 20 years old...

[rokcrawlin85]

Mark likes to help and do this kind of stuff specially in winter! But a little overwhelmed with life this afternoon... just found out my wifes brothers son (nephew) ended his life at 20 years old...

Holy crap!! I thought i was young. Very sorry to hear that Mark. I hope everyone gets through it ok.

[EagleMark]

Thanks!

Back to topic I found some interesting info below:

As I was told (and found out), the hardware is the same for all the c3's. And any C3 code will work on them.

Just as long as it has the WHOLE code on it, the 7747 will run just like an 8746 or whatever you make it to be.

So it's just a matter of what wires come out of the ECM compared to bin loaded on chip?

[rokcrawlin85]

So from a 8747 to 7747 there really isn't any changes needed to the bin, just load a 7747 with the $42 mask and burn a chip and put it into the 8747 ECM and watch it run. obviously changing a few things within the bin for a given vehicle and what it has as running gear.

[PJG1173]

I think what Eaglemark is saying is you may need to swap some wires on the ecu too.

[EagleMark]

So from a 8747 to 7747 there really isn't any changes needed to the bin, just load a 7747 with the $42 mask and burn a chip and put it into the 8747 ECM and watch it run. obviously changing a few things within the bin for a given vehicle and what it has as running gear.Well maybe a little termanoigy issue with that. Have to burn a $42 bin in chip and use in 8747 ECM. Yes apply any changes needed.


I think what Eaglemark is saying is you may need to swap some wires on the ecu too.Right!

[rokcrawlin85]

ok. well hopefully this weekend we'll be able to find something out with this. Mark i loaded up your Surburban tune into Tunerpro and will make any needed changes to make it initially run with my setup.

[EagleMark]

Well it's not tuned for your motor? It is tuned to a stock motor, hyway lean cruise enabled, ESC knock test done, PE increased, then that one had TCC turned off... we have a ton of other bins including that one stock in the 1227747 ECM information thread.

[rokcrawlin85]

isn't the suburban a stock hypertec chip or something like that? so it'll have a little more fuel and timing done i would assume... maybe i read that wrong. either way, i realize it's gonna take tuning to get stuff to work for my setup, just takes some time. i'll start with a stock base of a truck from late 80's early 90's era, and go from there. i'll start with one off this site that'll be a 5.7 700R4 truck bin for the 7747 ECM that way we can compare my changes, as i go, to a stock setup. Sound good?

[EagleMark]

Yup!

Comparing a Hypertech Stage 1 chip to stock there are only a couple minor differences. They should be arrested for any claims of improvement.

[gregs78cam]

Yea, I read one from a buddy's truck, and a couple of the changes made no sense to me.

[rokcrawlin85]

wow...i'll pass the word on to anyone looking into their chips then, scammers!! I'll just start with a fresh bin and go from there

[EagleMark]

Yea, I read one from a buddy's truck, and a couple of the changes made no sense to me.You can read years ago when hacking chips was in it's infancy an aftermarket chip maker sold a chip that increased fuel, and it did, they tested it and proved it. But they raised coolant temp so motor was always in choke...

[woody80z28]

I've looked all over the internet trying to find a good base vortec timing table for a tbi. I have read that a vortec tbi was offered from the factory in mexico but have yet to see a bin for it. There also seems to be a lot of debate at different forums on what vortec heads call for in reguards to timing in a tbi application. really comes down to cam, compression, fuel, ect. I can tell you when I put vortec heads on my 4.3 the stock tables were useless and it was a gutless wonder. I copied the timing table out of a efi live tune file and still had to bump it up across the board before the engine would come alive.

My stock timing table was terrible with the Vortecs too. I got a B-body LT1 table from TGO that helped a lot, but the best was from an LT1/6spd F-body. I took a few degrees out at high load (my truck is heavy) and left the rest of it about the same and it is great.

[PJG1173]

would you mind posting up a screen shot of your timing map? I've been looking at the stock 4.3 CPI table and it looks similar to my modified vortec table. I might give that one a shot.

[rokcrawlin85]

would you mind posting up a screen shot of your timing map? I've been looking at the stock 4.3 CPI table and it looks similar to my modified vortec table. I might give that one a shot.

x2 ^^ that timing table would be nice to take a look at and compare

[woody80z28]

When I get back to my home PC I'll post it up.

[EagleMark]

You guys could just go get the bin and open it. Auto and Manual are there...
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?335-16188051-and-16181333-PCM-Information-EE-EEB

[rokcrawlin85]

You guys could just go get the bin and open it. Auto and Manual are there...
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?335-16188051-and-16181333-PCM-Information-EE-EEB

Thanks mark, i just didn't know what ECM # was run in those LT1 setups to go find a staock bin... now i do

[EagleMark]

:thumbsup:

Prescott valley! I have a freind who lives in Cordes Junction, I love going to visit in the winter!

[rokcrawlin85]

I love this area up here!! Not too cold and not too hot. Could use some more green tho. But we got the woods to go wheel in less than 15 minutes away

[EagleMark]

Sedona, Montazumas castle, route 89 through Oak Creek canyon... and I missed my trip down there this winter... cold and broke...

[rokcrawlin85]

We're all broke now-a-days it seems. I was poor yesterday, i'm poor today, i'll be poor tomorrow. Oak Creek drive on 89 is a beautiful drive!! Love driving that way up to Flagstaff.

[EagleMark]

Oak Creek drive on 89 is a beautiful drive!! Love driving that way up to Flagstaff.OK we have to stop, I'm getting depressed... :innocent2:

[rokcrawlin85]

deal. get back on subject of tuning. when you were saying earlier about the 7747 being off by one ..... something, i forget now, but what do you mean by that? what's off compared to the 8747?

edit: byte word. that's what it was

[EagleMark]

It was the ADX file. $4F and $42 will work on each other.

NOTE: THIS DATA STREAM IS ALMOST IDENTICAL TO DATA STREAM A33 -WITH THE EXECEPTION TO BYTE 1 BIT 6 DEFINITION.


Which is $4F = 6 1ST TIME IDLE FLAG 0 = FIRST TIME
Which $42 is = 6 HIGH BATTERY VOLTAGE

So I just copied $42 adx and changed that byte... to make $4F adx

[rokcrawlin85]

there's some extremely smart people out there to understand and change that stuff around. nice work to everyone that helps us, no so smart, folk out :thumbsup:

[EagleMark]

Yeah really! We'd be screwed if it were up to me! :laugh:

I just got involved on the ADX files while Robert WENT ON VACATION without teaching me first!!! :mad1: Luckily he left behind enough for me to learn and reverse engineer. So if I can keep up on these he can put real talent to good use!

[rokcrawlin85]

ok, so i did a 7747 stock 5.7 truck bin burn. pulled my old chip out, put in the newly burned chip, and instant flashing CEL. Limp mode from the first start up, i guess there's other things that need to be done to get a 7747 bin to run properly in a 8747 ecm.

[EagleMark]

Sounds more like a bad burn or wrong offset or chip leg bent or install backwards... did you read the other thread? Pretty sure he used a 7747 bin and worked...
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?571-1228747-to-1227477-swap

[rokcrawlin85]

i have read that one over and over :thumbsup: i was thinking it would be pretty straight forward after reading it. i may have an issue like you posted with the chip. on that other thread, did he just run a 7747 bin in a 8747 ECM, the way it's writen it sounds like he used just the wires and connecters from the 8747 and just plugged them into a 7747 ECM, not just burning a 7747 bin into a 8747 ECM... that make any sense? i'll have to take a better look at the chip and make sure it was seated right too. i think its time to order a few more chips from moates...

[EagleMark]

He is now using a 1227747 ECM just plugged in the 1228747 harness! But earlier IIRC he used a 7747 chip successfully as well. Jim_in_dorris had looked up wiring harness details for us and mentions specific changes as we did not have 1228747 Wiring Diagram.

If any one has a 1228747 Wiring diagram we need one!!!

[rokcrawlin85]

ok, well i will certainly try burning another chip. making sure my offsets and everything match up correctly

[1leg]

I switched from a 8747 to a 7747 with no wire changes direct swap. The only issue i have is with my temp sensor and O2, nothing to do with the 7747 ecm.

FYI- I did try running a 8747 stock bin with the mask ID set to AA, in the 7747, still got the blinking CEL.

Sorry it took so long to find this thread. i guess i was too busy, turning and burning.

[rokcrawlin85]

I switched from a 8747 to a 7747 with no wire changes direct swap. The only issue i have is with my temp sensor and O2, nothing to do with the 7747 ecm.

Sorry it took so long to find this thread. i guess i was too busy, turning and burning.

so did buring a stock 7747 bin chip and placing it into the 8747 ECM never work right for you? You had to switch to the 7747 ECM before it would read the chip correctly?


FYI- I did try running a 8747 stock bin with the mask ID set to AA, in the 7747, still got the blinking CEL.

Isn't the mask id used for the 8747 $4F?

[1leg]

8747 computer stopped working all together, 7747 plugged in an.d ran with 7747 bin. I tried a 8747 bin in the 7747 just as test. It didn't work.

Using AA for a mask id, disables the checksum function, old jedi tuning trick I read some where.

[rokcrawlin85]

well that makes sense now. i'll have to try to burn another chip when i have time and test it out again in the 8747 to make sure it's the ECM to chip failure and not just the chip i burned.

disabling checksum does what exactly to an ECM?

[EagleMark]

disabling checksum does what exactly to an ECM?You change the maskID to AA while emulating, I've always changed it back when done, I don't know what it would do to ECM if left at AA?

[FSJ Guy]

You really shouldn't have to disable the checksum for chip burning. When you save the file, TunerPro should update the checksum for you.

Disabling the checksum prevents the ECM from "verifying" the binary file on the chip. Normally, it looks at the checksum to verify that the binary file is not corrupted.

[EagleMark]

I think the reason for AA to disable checksum while Emulating is because your changing the bin live...

[PJG1173]

I think the reason for AA to disable checksum while Emulating is because your changing the bin live...

is there a writeup around here on emulating? I always seem to have problems trying to emulate.

[EagleMark]

Moates has instructions on their website. If you need more than that start a thread and I'll try and help.

[1leg]

I only change it to AA on that chip to make sure it wasn't a check-sum fault that was causing my blinking CEL. when putting the 8747 bin in my 7747 to see if it would work. it didn't.