anesthes

iTrader: (12)

$325 for a harness?? wtf.

-- Joe

vortec77

yup

anesthes

iTrader: (12)

I'm in the wrong line of work. I could be converting junkyard harnesses in 30 mins flat, and selling 'em for half that!

-- Joe

vortec77

92blue

iTrader: (1)

Question: After repinning, will the ALDL signal be sent via pin E (like it was with the 746 stock), or is it sent via pin M like factory 730 cars do? I am under the impression that it will still be pin E right?

I'm trying to track down an ALDL problem. WinALDL works on other cars with my 2 resistor cable and laptop, but I can't get TunerPro, DataMaster, or Craig Moates 852 software to connect with the 730. I'm starting to think its in my wiring. I can read error codes by jumping A and B. I've verified pin A is grounded. Can I use a voltmeter to safely check pins E and M?

CrazyHawaiian

Really good info Joe!! Thanks!! I would go for it but I'm going TBI to MAF TPI. Anyone happen to have the re-pin charts for a 746 to 165 ECM? I also agree that re-pinning would be tons easier than running a new harness.

anesthes

iTrader: (12)

I could do one, but why? Besides, arn't you boosted? The '749 would be a much better choice for you.

I really would stay away from MAF. I spent a long time trying to tune maf. Went to SD and it was like instant relief.

-- Joe

CrazyHawaiian

Yeah I hear you there. I do plan to do the 749 for my 91Z, and I really gotta thank everyone on the board for providing so much info about these swaps. The TBI to TPI swap that I wanna do is on my 89 RS. We pulled the L03 and intended to swap in a carb'd 350 and use the car on the track only. But then I found a different 84 chassis with a cage for super cheap with no papers, perfect track car. So we decided to put the 89 RS back together for my girlfriend and convert it to TPI with left over MAF TPI parts. Not gonna happen for a while though, I still gotta find some LB9 heads. Are there diagrams on the boards with the 165 pinouts? I know I should probably be doing searches instead of posting ... hehehe. With what you posted here I should be able to figgure it out. Thanks for your help Joe, I really appreciate it.

anesthes

iTrader: (12)

Well.. if I have time i'll do a pinout conversion. LIttle tricky with the maf burnoff relays, etc.

vortec77

Isnt it harder to run a bigger cam with speed density than MAF? I read that its easier to swap a bigger cam in a MAF system than a Speed Density due to vacuum and computer adjust. problems??

Avenger007

So other than the knock sensor, what other sensors do we need to change out? I thought TBI guys needed to swap IAC, TPS and some other things. Is this a repin to keep the 7747 or what needs to be done to the existing 7730? Is a 730 a faster ecm?

great info...looks like ill be spending another whole day in the junkyard. How well will a V6 harness and 730 ecm swap into my 88 TBI? (ive already got a 7747 in there)

anesthes

iTrader: (12)

IAC, TPS will be on your new TB.

What would be a neat setup is if someone would convert a carb intake to EFI like I did on mine, and try the TBI throttle body unit on it with the injector pods and such removed. I'd like to hear how that TB works in a dry setup.

I went with the vortec TB on my setup, but I had to make an adapter to mount it.

-- Joe

Avenger007

How well will a V6 harness from a 92 camaro translate into my car? Will this take all the hastle out of repinning things?

Also im not familiar with IAC and TPS on Speed density (tpi) cars. Are they diff sensors than what are on TBI and I know their on the TB but do I need to buy new ones?

anesthes

iTrader: (12)

The v6 harness would have to be converted to a v8.

This how-to is the repinning of a harness. You would need a complete MPFI setup, either tpi, hsr, whatever .

-- Joe

Kat

iTrader: (4)

I did this swap over the summer for a friends car. Thats what I have for the pin outs. I corrected some of the wrong ones and added in the missing ones. That there "should" be the complete list.

Also coming off the 747 harness from C8 the PSPS (Power Steering Pressure Switch) and C9 (Crank Signal) Aren't needed at all. Unless you want to add in the PSPS to the 730 and have the idle kick up a bit while you are turning.

Kat

Avenger007

I went to the yard today and pulled 12 V6 injectors (19lb i believe), a V6 TPS and IAC and skipped the harness.

Will these work for my TBI to TPI conversion. I plan on following your repin how-to since I have a 7730. I know that MAP can be reused and Ive bought a new 91-92 knock. Ill be using HSR for the setup and just get a 58mm TB. Anything else?

Should I skip the 19# injectors and just buy a new set of 2_+# ones since ill be doing HSR on my 350. I thought maybe bump up PSI and compensate somehow on the 19# but im not sure.

86BirdSE

The IAC might not work. What "v6" injectors did you get... if they are 2.8/3.1 v6 injectors, they may not be enough.

"Many Mild 350 TPI applications need a 24lb injector... stock on 1990-1994 3800 series I tuned port engines is a Bosch 24lb injector. These motors are finding their way into the yards more and more. I got 6 of my 8 injectors form a 48,000 mile motor. the other 2 a 64,000 mile motor. They are currently being sent to be flow matched and cleaned. I got all six form the second car, in case any were bad. I think the harnesses and the injectors ran me about $40 at the U-pull-it yard near my place." ---- From my earlier post

Quad-4 engines have a really nice injector harness I adapted to a TBI harness as well... just as a tip for those trying to piece together v6 wires.

pandorafowler

For the wiring of the connectors, which side is it positive on the injectors? I`m getting new connectors from work and need to know what side of the injector connects to the green/blue wires

Chrome

92 did you ever find an answer to this??? I am getting ready to start this conversion with a stock l98 and HSR and I am planning buying an AUTOPROM. Only concern is after I repin is the ALDL going to be the same as a factory 730 ALDL??? If not can the AUTOPROM even work without modifiying it?!?!? Thanks.

Kat

iTrader: (4)

I used the AutoProm on the said 88 TA that I did the conversion to. It worked fine for me. IIRC E and M both get the same signal on the ALDL

Kat

92heritageRS

Just found a good site with schematics of all the ECMs
http://www.cruzers.com/~ludis/schema...l#1228746.html


Hope it is helpful for you guys who know how to use them.

92heritageRS

This also makes it easier to understand

http://chevythunder.com/fuel%20injec...%20pinouts.htm

thirdgen88

I'm in the process of doing a MPFI conversion on my brothers '91 TBI car... I ended up with a few wires, among them was the PSPS (power steering pressure switch)... The V6 7730 applications utilize that PSPS at pin BD13.. A simple change in the PROM should allow those with this switch to still use it with 7730... So, if you have switch in the pressure hose on the power steering, and a Lt. Blue wire at pin C8 (PSPS) on your '8746, then you should be able to put that pin at BD13 on the '7730.. Then just change Bit 6 at L8019 in the prom to 1, and you have a working power steering pressure switch system... Better then leaving it out, if you have it, might as well enable it...

Chrome

I'm now about a week from starting this conversion. 3 Questions.

1) Did you guys pull the harness from the computer, or just do it inside the car?

2) Can you purchase the quad-4 harnesses new from GM, if so does anyone know the part# or price?

3) What A/C problems did you encounter because I've heard that is one of the only major circuit differences between TBI and TPI?

I wonder if you stay with the TBI single fan what I would have to do?

Thanks!

86BirdSE

Quote:

2) Can you purchase the quad-4 harnesses new from GM, if so does anyone know the part# or price?


Thanks!

No clue, but I have a slew of used ones in good shape I'll send ya cheap. Shoot me a PM if you're intrested.

thirdgen88

I did it inside the car... Its not too bad, plus the floorboard makes a good spot to place the notes and papers so you can see them as you work... One thing to make sure is that you keep track which connectors are the old ones that you are transferring pins FROM and which are the new connectors that the pins go TO... About midway its easy to pull a pin from the 7730 connector and get confused (hehe... ummm, yup, you guessed it, thankfully I didn't get myself all out of whack)... One thing I suggest is to get a system set up to triple check each wire transfer (verify that the wire you are pulling is the right color and in the right spot, then pull the pin, then verify that the spot you're putting it in is the correct spot/function, then verify the wire color again, etc)...

Quote:

3) What A/C problems did you encounter because I've heard that is one of the only major circuit differences between TBI and TPI?

I don't recall A/C having any different operating characteristics on the '91 TBI harness I'm converting... I only ended up with a few left over wires at the ECM end (a couple wires for the Injector 1 and Injector 2 + (there are two wires for each injector + for some reason, they're connected inside the ECM), a wire for Crank Signal (not used in '7730?), the PSPS (power steering switch, mentioned above))...

Quote:

I wonder if you stay with the TBI single fan what I would have to do?

I haven't gotten around to this yet on my conversion, but I'm planning on running another wire (along with some additional Sys. Grnd wires while I'm at it) for to let the ECM control the single fan (just like it controls the primary fan of a dual-fan TPI setup)... Should just be able to run a wire to the Negative coil feed on the fan relay, and wire that to GE8 (Cooling Fan Control)..

Kat

iTrader: (4)

Thats what I did. Actually I was lazy and ran it to the wire that went to the manual fan switch inside the car. Works quite well.

Kat

Chrome

Bump good info.

I'm doing this swap actually w/ TPI now (HSR funds went south, heh). I'm hoping to try and document and take pictures. Probably start a new thread but hopefully it will help people out.

BTW, I've read differing opinions on changing fuel lines from TBI to TPI. I think you only have to change the rubber fuel lines, but just looked at a thread where a individual said the rubber fuel lines from tank to chassis are the same part numbers on TBI and TPI. The only ones that are different and need to be changed are the rubber lines from Fuel Rail Lines to Chassis in teh engine compartment. And said individual even said that the return in the engine compartment is the same (TPI or TBI). With all of this differing answers any body have "proof" like actual part numbers or whatnot. ??? Thanks

Kat

iTrader: (4)

Here is the definitive answer..

When I did the TBI -TPI swap on the 88 TA I used the original TBI rubber lines going to the TPI fuel lines.

Kat

thirdgen88

Okay, fired up the conversion today (and drove it home!)... Some notes for people doing this conversion... All went as planned except for the speedo... Initially I had no speedo input to the ECM (and hence no TCC lockup)... The speedometer on the instrument cluster worked fine though. If you pull the cover off the passenger side (as shown in the pics), and splice wires off of the connecter going to the VSS Buffer box and run the Purple (PPL) to BB9 (VSS Low) and the Yellow (YEL) to BB10 (VSS High), you will have proper speedo operation for the ECM... Easy enough since the buffer box is right there..

thirdgen88

Oh, and one note, don't bother with the quad 4 injector harnesses... You have to hack them up in order for them to work well since our injectors aren't evenly spaced (they are grouped in pairs)...

Also, I just deleted the factory fan switch... You can extend the wire running to the passenger cylinder head fan switch and plug it into GE8 (Fan Control) on the ECM...

Here are the wires spliced and routed toward the ECM:

RED92BIRD305

i have my intake and my Injector harness and my 7730 ecm. all i have to get is a fuel rail and injectors and fuel pump and filter.will the connectors off of my 92 TBI harness Plug into the 7730 or do i need to order the connectors also. my car is a 1992 L03.

Kat

iTrader: (4)

You need to get a few more ECM connectors from a junk yard or some other place.

As for the Speedo issue. The way that you did it works since the VSS puts out 4000 ppm (what the 7730 ECM needs) where as the VSS Buffer only sends 2000 ppm to the ECM (what the TBI puter needs and the 165 ECM). All I did was flip the switch in TunerPro from Mag VSS to Optical and that made the speedo work.

Kat

thirdgen88

The speedometer worked fine.... It was the ECM speed input that wasn't functioning... I tried flipping that same bit with no effect... There was no vehicle speed in the datalogs until I hooked that up as described... This means you won't get torque converter lockup and other miscellaneous things...

RED92BIRD305

would a part store carry those connectors or would i have to find them in a yard

thirdgen88

Find them in the yard so you also can get a lot of extra pins (you will need 3 or 4 additional pins to run extra grounds and/or fan control)...

WhiteGhost

Ok I have read this thread twice.. and I must say I discovered that I am retarded.. So let me try to answer my question like this.. hypothetically.. I bought a TPI converstion off ebay.. tuneport intake, harness, computer.. the first question is, if I do it that way do I need to make sure its a speed density car or since I wont be using the computer, just the chip, does it not matter what year the tunport setup is off of?? Until I get my answer on that question I will keep things easy and say its a speed density setup.. I switched the fuel pump, installed the tuneport intake, and connected the fuel lines.. I unplugged my old computer and set it aside.. so now I am looking at X number of plugs and the new computer that came with the speed density tuneport set up with emply plugs attached to it (took all the wires out of the plugs of the new computer).. which diagram would I need, to know which wires to pull out of the plugs and move them to whereever.. I get the idea.. but on the charts listed in this thread there are several that are either blank, or have a (*).. what I would think would be extremely helpful is if somone could explain it for the retards out there like myself kinda like this.. take wire X from pin X and move it pin X on the new connector.. then take wire X from pin X and move it to pin X on the new connector.. and so on, and so on... I know it would be alot of trouble for someone to write that up but it would make it so that a 2 year old could do this.. (myself) LOL.. I was totally conviced I was going carb until I found this thread.. now if I can get it to make sense in my head and be as easy as you all make it sound I will definatly go with the tuneport..
oh one last question.. I can extend wires as needed with no problem at all.. but when i cut the 8 injector wires off and splice them in the TBI harness.. what colors go to what colors?? From what I can tell if you trace the TPI harness back all 16 injector wires (2 wires per injector) eventually become 4 wires.. right?? where they become 4 is where I would want to cut the harness and splice it in... Since I couldnt drive the car to have someone do this for me I honest to *** would pay someone to write the article I am asking for.. I think it would do alot of people alot of
good.. If someone would write this up for me I seriously would pay them as long as it came with some guarentee that it would work.. Just in case your interested we will stick with the assumtion I bought a speed density set up.. my car is a 92 camaro with a T-5.. and single fan, with A/C (if that matters).. and I dont care about whatever that power sterring thing is...
Thanks

thirdgen88

There is a blue wire and red wire for one of the injectors, and a green wire and white wire for the other injector... You will have four injectors on each side, with two wires coming finally off of each... Connect the blue and red to wire 1 and wire 2 on one side, and connect the green and white to wire 1 and wire 2 on the other side...

WhiteGhost

Someone sent me an AWESOME wiring diagram and I replied to their email.. I am just going to copy and paste what I replied to him since it works here also.. What he sent me was diagrams showing exactly what wire goes where on the V6 and TPI computers.. basically what the diagrams showed me is that if I had a 350 TPI car from factory I would know exactly what each wire was for, where it was supposed to be and all that.. I still need to know which wires from the orginal TBI harness goes into which holes on the new 7730 connectors. This is the email I sent him..

Ok.. this is where I am at so far with the information you supplied me.. If I bid on ebay on a Tuneport setup that comes with the 7730 computer and harness, I will know exactly what wires goes where, what they do, what color they are, everything like that.. What I am still at a stand still on is this.. I have the tunport computer with the empty connectors (since I pulled the wires out of them).. I also have my old connectors dangling where they used to plug into the computer.. I need a diagram or written manual on exactly which wires to pull from the orginal connector hanging in the car and where to place them in the new connectors on the 7730 computer.. I hope that makes sense.. I wish I could have someone standing here with me looking at it and show them what I am trying to explain.. oh well.. Here is a little thing I did in paint to show you what I am looking at.. (attached file)

Well crap, the picture is too small to read the words.. maybe he knows how to post it bigger but I dont.. sorry

92heritageRS

WhiteGhost,
Here's a visual of the pin locations and how you find the pin you're looking for. I would go thru and label all the wires on your harness with tape so you don't get lost. Its work but it helps. This picture is of the 7730 ECM plugs. I have also found that a service manual helps alot as a reference between the two ECMs, and the differences between the VIN E and 8/F harnesses. Any other pics you need I will try to post. I have a 92 RS 305 with T-5 and I am switching to HSR and 7730. I can take pics of the pages in the GM service manual if you like also for more of a visual. Let me know if I can help. By the way you have mail!

92blue

iTrader: (1)

I haven't really been keeping up on this thread, just read it for the first time in months this morning.

It turned out my problem was not wiring related. Both pin E and pin M will provide the aldl data as I later found out.

Also, I ended up fixing the vss to the ecm problem (ecm wasn't getting a vss signal), by switching the Mag vs. Opt Vss bit in the memcal. I have the vss wired in on pin BC6. That way, I didn't have to mess with the vss buffer box. Its still in place, and so is my Dakota Digital SGI-5 box for my 6 spd. I haven't touched any of that at all.

Its been a while since I did the harness conversion, and I have to admit I was expecting to find some wiring screwups on my part. To this day, everything is functioning as it should. Of the problems I have come across, none so far have been wiring problems. I highly recommend this to anyone looking to do a TBI to TPI conversion.

thirdgen88

Agreed, this is definately the way to go from TBI to port injection (whether it be TPI, LT1 intake, or HSR)... Great procedure.. The feedback that we are getting from people who have done the conversion I think is making this procedure more and more refined... I'm thinking about doing a write-up on it this summer..

hot68

Thought I'd bring this up to the top again...I'm about to repin our 91 tbi 'bird to a 91 tpi. I don't quite uderstand the VSS issue what I would need to do on this part of the swap. I don't have the ability or knowlege to alter the prom so I would be using a stock 305 730 calibration. If I understand correctly the tbi uses a 2000 pulse and I need to change to a 4000 pulse for the tpi. Can I do this as pictured in an earlier post.

thirdgen88

Yeah, the procedure I listed was even performed on a '91 TBI bird... That will work just fine for you, and you won't have to alter the PROM.

hot68

Great! thanks for the quick response

GCash

I just read this whole thread and it helped me out alot. I have an 87 305 TPI MAF setup. the intake is on and all that, just doin wiring now. Now this setup is going into a coughS10cough. If i do this repinning stuff and make it a SD setup will it run funny with my cam. I don't have the numbers by me, but i put in a 214/443 hydraulic cam (84 block) the camaro had a mechincal speedo, my s10 has an electrical? What do i have to do to make that work. And with the injector wires, I have the harness off the camaro, so i can pull those injector wires and the iat (sensor on bottom of upper plentum right?) and just feed those into my TBI harness right. then change my knock sensor. My TBI had an engine driven fan, and the camaro had dual electric fans. Will i have a problem if the compter sees that those arn't hooked up? Thanks for any advice you guys have.

GCash

If i can get a response that would be great

I have a hacked up 87 camaro harness, and instead of trying to fix it, i decided to take the wires out of it that i needed and put them into my 90 TBI S10 Harness. I got pin out diagrams for both vehicles and began moving over the wires i needed here are a couple of my questions

- I don't know what the previous ower did, but there a wires spliced and cut and everything else in the MAF portion of the harness so I have deceided to go to speed density. It'll probally be easier on me anyway.
1) Just to vairify in the chart on the first page. I has 2 columns, 730 and 747, the 730 colum has BA11 Fuel pump relay and the 747 coulum has A1, that means i have to move the wire in A1 to A11 right?

2) Will the TBI ECM connectors fit the 730 ECM and all i have to do is get the Green Eand F connector and move the wires over listed in the chart?

3) I went ahead and picked up some Flex a lite 210 e-fans and they come with there own switch will it be ok if the computer sees the fans arn't there or will it always act like it's hot or cold?

4) I'm gonna purchase some aftermarket gauges, now can i just buy a mechcanical spedo or does it have to be electric. My truck has an electric speedo from the factory, but it took a dump on me, don't know if it's the gauge itself or what. I replaced the sensor in the trans, and that didn't do anything. I would rather put in a mechcanical if i can.

Sorry for all the questions, figured i ask them all at once any help would be greatly appreciated.

thirdgen88

1) Yup, make sure to double check each pin movement so you don't lose track or make any mistakes that will take a lot of time to trace down later.

2) Yup, you just need the 3rd additional connector. However, you should get an entire set of '730 connecters, that way you can move the pins from your old harness to the new one without having to reuse the connecters (potential confusion source). Make sure to keep track of which one is the old connecter (sounds funny, but I made that mistake a couple times (caught it thankfully) when I was halfway through the procedure).

3) The ECM won't care if there isn't a fan connected to the pins. You might consider having the ECM trigger the relays, this way you can control the on temps much more closely than with the mechanical switches.

4) The '730 will need an electronic VSS signal. You might look at the VSS box that I mentioned a few posts back.

406TPI

iTrader: (1)

Hey guys...great thread!

I just repinned a 747 to a 730. Everything went great thanks to this thread. I have one problem though.....I am getting a constant code 41....anybody run into this? Very strange.

Thanks,
James

GCash

Cool, thanks alot fo all the help now I got a couple more questions, lol

1) Is the TBI and TPI map sensor the same?
2) Is the MAF and MAP knock sensors the same (pick up 87 k/s)
3) It's hard to get TPI stuff around here, it's gone before it even comes into the yards. In the begining of the thread it mentioned that a quad 4 ecm (1227749) will work with a V8 memcal, i can get a quad 4 ecm for like 10 bucks and just cut the wires after the connectors, should i do this? where can i get a v8 memcal

4) Last question, my vss, what do you recommond it do? Should i get electronic speedo it comes with senders too (http://www.autometer.com/cat_accesso...st.aspx?pid=28) which one should i get, can i wire it into my stock vss? my speedo wasn't working though when i parked it.

Thanks again