5.7 vortec swap need help/advice

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1sik78

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So I got this 5.7L vortec complete with transfer case and trans(free). Looking to swap it in my 78 swb c10 2wd. Does anyone know where I can get info on how to directly running this setup how it is. On what wires need to be used ect. Or what do do to run it carbureted. This is a freebie so I would like to stick it in place of my inline 250 it currently has. Any advice or help would be appreciated thanks in advance
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Well, these are just my opinions, but first of all, go ahead and sell that transfer case because GMT 400 cases are driver side drop and rounded line transfer cases are passenger side drop. They just don't match. Second, if that transmission is a 4L80E, I would drop that thing in there in a New York minute. If that's the case, you can purchase a stand alone computer and do whatever modifcations to the driveline. Same thing for an NV4500 minus the computer. Even if the transmission you got is a three speed automatic or a Saginaw Muncie, I'd still hold onto it. The engine is a different story. The good news is that the Vortec is the last incarnation of the very common Small Block Chevy, and it performs exceptionally well. It would add a lot of enjoyment to the experience of your truck if you just left it in its form. The downside, in my opinion, is that this particular engine is an OBD II engine, which has a lot of sensors and stuff, and that it would probably be a good idea to work withthe ECM and harness of a similar truck. Most of the sensors are already on the engine but some (i.e. Oxygen Sensor) would have to be added. People on here do the more complicated swaps to Gen III (LS) motors with commendable success, and this is an easier swap. I think you should go for it with the Vortec like it is, given that you can preserve the functionality of your accessories when you do it. I think it would make your truck a lot more fun.
 

1sik78

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Well, these are just my opinions, but first of all, go ahead and sell that transfer case because GMT 400 cases are driver side drop and rounded line transfer cases are passenger side drop. They just don't match. Second, if that transmission is a 4L80E, I would drop that thing in there in a New York minute. If that's the case, you can purchase a stand alone computer and do whatever modifcations to the driveline. Same thing for an NV4500 minus the computer. Even if the transmission you got is a three speed automatic or a Saginaw Muncie, I'd still hold onto it. The engine is a different story. The good news is that the Vortec is the last incarnation of the very common Small Block Chevy, and it performs exceptionally well. It would add a lot of enjoyment to the experience of your truck if you just left it in its form. The downside, in my opinion, is that this particular engine is an OBD II engine, which has a lot of sensors and stuff, and that it would probably be a good idea to work withthe ECM and harness of a similar truck. Most of the sensors are already on the engine but some (i.e. Oxygen Sensor) would have to be added. People on here do the more complicated swaps to Gen III (LS) motors with commendable success, and this is an easier swap. I think you should go for it with the Vortec like it is, given that you can preserve the functionality of your accessories when you do it. I think it would make your truck a lot more fun.


Thanks for the feed back so for the trans do I need to convert it so it can be in a 2wd form. Since it originally had 4wd? Yes and I have been looking into a 5.3 swap as well I would prefer 5.3. If it's too much more complicated to do the 5.7 then I'll see if I can sell it and see if I can come across a decent 5.3 or 6.0 ls


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I would assume so since there is no transfer case coupled to yours, and there was to that one. Honestly, I'm not an LS bandwagoneer. I like the idea of swapping to a Vortec 350 much more because it's more authentic to the truck. That truck was designed to have one of the long gone inline sixes or the Small/Big Block Chevy so the hardware component will be very compatible with your truck. It's the software that makes the endeavor more complicated. If you do decide to go with an LS swap, you have plenty of resources here to help the process.
 

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I would assume so since there is no transfer case coupled to yours, and there was to that one. Honestly, I'm not an LS bandwagoneer. I like the idea of swapping to a Vortec 350 much more because it's more authentic to the truck. That truck was designed to have one of the long gone inline sixes or the Small/Big Block Chevy so the hardware component will be very compatible with your truck. It's the software that makes the endeavor more complicated. If you do decide to go with an LS swap, you have plenty of resources here to help the process.


Very true, I'm going to try and stick with the 350 and see how it goes. If I need to carb it to avoid all the computers and sensors then I'll do that. I know I can get an intake and distributer for the swap right and carb of course


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Good deal. And remember, the electronic aspect of the swap may sound like a bitch, but you earn a smoother, more efficient power plant that delivers fuel with evenness and precision that a carburetor is not capable of. I think you'll really have a great machine with that engine and transmission swap regardless of how you do it. Good luck!
 

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I would not hesitate one bit dropping that power unit in that truck. It is actually a pretty straight forward swap.

The Transmission WILL need to be torn apart and have the output shaft switched to a 2wd. That is a pretty basic job do it your self and save some money or pay a shop and have it done. Myself or @HotRodPC either one would be capable of converting that transmission to 2wd, (I'm sure there are other members as well).

It is really your choice on if you went to a Carb or stayed with EFI. I personally am a big EFI fan, there is information on the web on how to re-wire the harness to delete the ******** that is not needed. Or if you don't feel comfortable with doing it yourself you can always send the harness off and have it done for you. this service usually runs about $250.00 I do re-wires as well as build custom harnesses send me a PM if your interested in this and I will be happy to discuss the option more in depth

I have done several of these swaps and would be more then happy to help you out along the way. If you could post all the particulars of your current set up as well as the particulars on what the donor engine and transmission was removed from.
 

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I would not hesitate one bit dropping that power unit in that truck. It is actually a pretty straight forward swap.



The Transmission WILL need to be torn apart and have the output shaft switched to a 2wd. That is a pretty basic job do it your self and save some money or pay a shop and have it done. Myself or @HotRodPC either one would be capable of converting that transmission to 2wd, (I'm sure there are other members as well).



It is really your choice on if you went to a Carb or stayed with EFI. I personally am a big EFI fan, there is information on the web on how to re-wire the harness to delete the ******** that is not needed. Or if you don't feel comfortable with doing it yourself you can always send the harness off and have it done for you. this service usually runs about $250.00 I do re-wires as well as build custom harnesses send me a PM if your interested in this and I will be happy to discuss the option more in depth



I have done several of these swaps and would be more then happy to help you out along the way. If you could post all the particulars of your current set up as well as the particulars on what the donor engine and transmission was removed from.


Oneluckypops thanks soft the info I am sticking to this now.

Current set up stock 250 inline 6 with turbo 350 3speed automatic. 78 short bed fleet side c10

As far as I know the engine was out of a 97 suburban 4wd.

So first the wiring harness. I have been looking all over the web on how to modify the harness or what wires you need just to start it up but I have not been able to find anything. I would like to do it myself but if there is not a how to out there then will definitely send it out to be done. Do you need to flash the ecu first to remove (vat) anti theft?

Second the trans. I need to find the same one but in 2wd so I can switch what I need right? And the computer of the engine will control it I don't need to get another computer just for the tranny?
It currently has a turbo 350 3speed if for the time being I can't get the tranny in can I use this trans?




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If you're staying with your Turbo 350, then stay with it. It'll bolt up just fine to the Vortec 350 and stay in the same location, same mounts, driveshaft etc. There is only 1/2 in difference in the 2wd 700r4/4L60-E and the Intermediate Shaft (9in that most refer to as long shaft, but there is also a 12in tailshaft too that is uncommon) Th350 so usually there is enough space in the slip yoke you usually don't even have to swap driveshafts on a Th350 to 700r4 conversion or vice versa. In this case, it should be easy to get the vortec 350 in if you're going to carb it. Now you will have to make a few mods to convert from the I6 250 to the V8. Things like exhaust of course, the throttle cable, fan shroud etc.
 

1sik78

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If you're staying with your Turbo 350, then stay with it. It'll bolt up just fine to the Vortec 350 and stay in the same location, same mounts, driveshaft etc. There is only 1/2 in difference in the 2wd 700r4/4L60-E and the Intermediate Shaft (9in that most refer to as long shaft, but there is also a 12in tailshaft too that is uncommon) Th350 so usually there is enough space in the slip yoke you usually don't even have to swap driveshafts on a Th350 to 700r4 conversion or vice versa. In this case, it should be easy to get the vortec 350 in if you're going to carb it. Now you will have to make a few mods to convert from the I6 250 to the V8. Things like exhaust of course, the throttle cable, fan shroud etc.


I'm am going to go with the way it is no carb. Where can I find the throttle cable that I need for the vortec? And that kick down for the trans if I stick with the th350. Is there a topic on here that can give me the info I need?






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Oneluckypops thanks soft the info I am sticking to this now.

Current set up stock 250 inline 6 with turbo 350 3speed automatic. 78 short bed fleet side c10

As far as I know the engine was out of a 97 suburban 4wd.

So first the wiring harness. I have been looking all over the web on how to modify the harness or what wires you need just to start it up but I have not been able to find anything. I would like to do it myself but if there is not a how to out there then will definitely send it out to be done. Do you need to flash the ecu first to remove (vat) anti theft?

Second the trans. I need to find the same one but in 2wd so I can switch what I need right? And the computer of the engine will control it I don't need to get another computer just for the tranny?
It currently has a turbo 350 3speed if for the time being I can't get the tranny in can I use this trans?




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I'm am going to go with the way it is no carb. Where can I find the throttle cable that I need for the vortec? And that kick down for the trans if I stick with the th350. Is there a topic on here that can give me the info I need?






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I will be back on later tonight and I will try to answer more in depth what you will need. but as for the VATS system, if it is TRULLY a 97 then it will NOT have vats installed. 98 is when they started that crap.
 

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I'm am going to go with the way it is no carb. Where can I find the throttle cable that I need for the vortec? And that kick down for the trans if I stick with the th350. Is there a topic on here that can give me the info I need?






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OK, so I misunderstood. You are going to keep the SFI (Sequential Fuel Injection)? So yes, the Th350 will still bolt up, but... and luckypops can tell you if you'll need to reburn your chip to delete the transmission, and then the other issue to deal with if you using the Th350 is the VSS (Vehicle Speed Sensor). The ECM will need it. There is a couple ways to handle that too. If were me, if you're doing the ECM and wiring, I'd just get the 4L60-E converted to 2wd and go for it all at once so you have your wiring done, chip burnt all at one time and be done.
 

1sik78

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OK, so I misunderstood. You are going to keep the SFI (Sequential Fuel Injection)? So yes, the Th350 will still bolt up, but... and luckypops can tell you if you'll need to reburn your chip to delete the transmission, and then the other issue to deal with if you using the Th350 is the VSS (Vehicle Speed Sensor). The ECM will need it. There is a couple ways to handle that too. If were me, if you're doing the ECM and wiring, I'd just get the 4L60-E converted to 2wd and go for it all at once so you have your wiring done, chip burnt all at one time and be done.


I like your suggestion, I'll convert it and just be done with it all together I'll start going to local trans shop to see if they have one laying around because finding one in the junk yards will be 4wd


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oneluckypops

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Oneluckypops thanks soft the info I am sticking to this now.

Current set up stock 250 inline 6 with turbo 350 3speed automatic. 78 short bed fleet side c10

As far as I know the engine was out of a 97 suburban 4wd.

So first the wiring harness. I have been looking all over the web on how to modify the harness or what wires you need just to start it up but I have not been able to find anything. I would like to do it myself but if there is not a how to out there then will definitely send it out to be done. Do you need to flash the ecu first to remove (vat) anti theft?

Second the trans. I need to find the same one but in 2wd so I can switch what I need right? And the computer of the engine will control it I don't need to get another computer just for the tranny?
It currently has a turbo 350 3speed if for the time being I can't get the tranny in can I use this trans?




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Ok first things first, You will not regret this repower. No there not as peppy as the LS motors but they are in deed a HUGE improvement over the earlier carbed and TBI 350's. Considering you are swapping from an inline 6 you may nut all over yourself the first time you punch it.

There are "how too" out there for modifying the harnesses on these engines, but honestly I was never real impressed with any of them that I ever came across. Some people get really discouraged when they have to look at wiring diagrams, and most of the how tos I have seen all revert back to diagrams at some point. For some this is no big deal, I myself love electricity no matter if its 12v-480v. Depending on your skill level I can either help you by giving you the diagrams, or I can convert them in to an easy to follow spread sheet, (remove this wire, hook this wire to this pin, ect.)

The engine is made to fit in your truck, How ever I do believe you will have to change the location of the motor mounts on the frame. IIRC the mounts are in different locations for v8's then they are for I6's. Still an easy fix.

The Transmission can easily be converted to a 2wd application. You would need a seal kit, well actually just a pump gasket, pump O-ring, pan gasket, and valve body gaskets. But may as well go ahead and get a paper and rubber seal kit. It will be cheaper. The other parts you will need would be a 2wd tail shaft, and 2wd tail housing. You can buy these parts from a transmission supplier or you can look for a core transmission to get the shaft and housing from. LOTS OF YEARS WILL INTERCHANGE so long as it has the same number of bolts for the housing 97 should be a 4 bolt design. Oh and a reluctor ring for the VSS (vehicle speed sensor). If you bought a core it would already have the reluctor ring on it.

A little lesson on computers. You have probably already seen or heard the terms VCM, PCM, ECM, TCM, BCM. They are essentially all the same thing. Different years used different terminology and the newer you get the more jobs they have to do. Now what they actually stand for and what they actually do.
VCM=Vehicle Control Module. Controls Engine, Transmission, and sends and receives signals to the BCM, EBCM, and TCCM.
PCM= Powertrain control module, basically controls all of the same functions as a VCM PLUS it also controls traction control.
ECM=Engine control module. controls the engine
TCM=Transmission control module. controls the transmission
BCM=Body control module
EBCM=Electronic brake control module. Controls antilock brake systems
TCCM=Transfer case control module. Controls the transmission.
The computer you will use is actually called a VCM so YES the computer for the engine will control the transmission so no need for an additional computer.
96-97 vortec trucks were NOT equipped with "VATS" (vehicle anti theft system) so technically you can use the computer with out doing any reprograming to it. Now I would how ever recommend having it re-flashed for a couple of reasons. #1 you will want to delete all the emissions crap on the engine. If you don't re-flash it after you do that you will automatically have a SES light on which will lower your MPG as well as not allow you to know if anything else is wrong down the road. #2 you will want to correct the programming for gear ratio, and tire size.

As for using the TH350 Transmission if you cant get the tranny converted. Technically you can use it. HOWEVER if the VCM does not see a signal from the VSS it will experience Idle learn problems because the VCM takes readings from the VSS to help with engine load% which will cause POOR fuel economy and drivability issues. So no matter what transmission you use you will have to get a VSS signal to the computer.

OK, so I misunderstood. You are going to keep the SFI (Sequential Fuel Injection)? So yes, the Th350 will still bolt up, but... and luckypops can tell you if you'll need to reburn your chip to delete the transmission, and then the other issue to deal with if you using the Th350 is the VSS (Vehicle Speed Sensor). The ECM will need it. There is a couple ways to handle that too. If were me, if you're doing the ECM and wiring, I'd just get the 4L60-E converted to 2wd and go for it all at once so you have your wiring done, chip burnt all at one time and be done.

The main issue of the 3 speed is of course the VSS. As far as the Transmission controls being deleted from the VCM. It would be a good idea to disable the automatic and reconfigure the parameters as a standard transmission. The reason is LIMP MODE, Limp mode in these trucks is nothing more then a 3rd gear start.
When the VSS determines 1-2 shift is needed the th350 doesn't have the ability to receive that signal so the VCM will then trigger a code for 1-2 shift time to long causing the VCM to go in to Limp mode. the only problem it will cause will be a SES light. Can you drive it? YES is it a good idea? NO!!!! the ses light needs to be able to inform you of problems that are going on and if the light is already on you will not be aware of any other problems that may arise.
 

1sik78

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Ok first things first, You will not regret this repower. No there not as peppy as the LS motors but they are in deed a HUGE improvement over the earlier carbed and TBI 350's. Considering you are swapping from an inline 6 you may nut all over yourself the first time you punch it.



There are "how too" out there for modifying the harnesses on these engines, but honestly I was never real impressed with any of them that I ever came across. Some people get really discouraged when they have to look at wiring diagrams, and most of the how tos I have seen all revert back to diagrams at some point. For some this is no big deal, I myself love electricity no matter if its 12v-480v. Depending on your skill level I can either help you by giving you the diagrams, or I can convert them in to an easy to follow spread sheet, (remove this wire, hook this wire to this pin, ect.)



The engine is made to fit in your truck, How ever I do believe you will have to change the location of the motor mounts on the frame. IIRC the mounts are in different locations for v8's then they are for I6's. Still an easy fix.



The Transmission can easily be converted to a 2wd application. You would need a seal kit, well actually just a pump gasket, pump O-ring, pan gasket, and valve body gaskets. But may as well go ahead and get a paper and rubber seal kit. It will be cheaper. The other parts you will need would be a 2wd tail shaft, and 2wd tail housing. You can buy these parts from a transmission supplier or you can look for a core transmission to get the shaft and housing from. LOTS OF YEARS WILL INTERCHANGE so long as it has the same number of bolts for the housing 97 should be a 4 bolt design. Oh and a reluctor ring for the VSS (vehicle speed sensor). If you bought a core it would already have the reluctor ring on it.



A little lesson on computers. You have probably already seen or heard the terms VCM, PCM, ECM, TCM, BCM. They are essentially all the same thing. Different years used different terminology and the newer you get the more jobs they have to do. Now what they actually stand for and what they actually do.

VCM=Vehicle Control Module. Controls Engine, Transmission, and sends and receives signals to the BCM, EBCM, and TCCM.

PCM= Powertrain control module, basically controls all of the same functions as a VCM PLUS it also controls traction control.

ECM=Engine control module. controls the engine

TCM=Transmission control module. controls the transmission

BCM=Body control module

EBCM=Electronic brake control module. Controls antilock brake systems

TCCM=Transfer case control module. Controls the transmission.

The computer you will use is actually called a VCM so YES the computer for the engine will control the transmission so no need for an additional computer.

96-97 vortec trucks were NOT equipped with "VATS" (vehicle anti theft system) so technically you can use the computer with out doing any reprograming to it. Now I would how ever recommend having it re-flashed for a couple of reasons. #1 you will want to delete all the emissions crap on the engine. If you don't re-flash it after you do that you will automatically have a SES light on which will lower your MPG as well as not allow you to know if anything else is wrong down the road. #2 you will want to correct the programming for gear ratio, and tire size.



As for using the TH350 Transmission if you cant get the tranny converted. Technically you can use it. HOWEVER if the VCM does not see a signal from the VSS it will experience Idle learn problems because the VCM takes readings from the VSS to help with engine load% which will cause POOR fuel economy and drivability issues. So no matter what transmission you use you will have to get a VSS signal to the computer.







The main issue of the 3 speed is of course the VSS. As far as the Transmission controls being deleted from the VCM. It would be a good idea to disable the automatic and reconfigure the parameters as a standard transmission. The reason is LIMP MODE, Limp mode in these trucks is nothing more then a 3rd gear start.

When the VSS determines 1-2 shift is needed the th350 doesn't have the ability to receive that signal so the VCM will then trigger a code for 1-2 shift time to long causing the VCM to go in to Limp mode. the only problem it will cause will be a SES light. Can you drive it? YES is it a good idea? NO!!!! the ses light needs to be able to inform you of problems that are going on and if the light is already on you will not be aware of any other problems that may arise.


That is a lot of great info definitely answered all my questions by far thank you so much. As far as the wiring I would like to see the spread sheet i like working with wires too. And volts. I am up for the challenge can't wait to get on this build. I'll be on the look out for the trans parts as well. If I find one that is out of a 96-97 and is 2wd can I just take it and run it. Maybe a fresh rebuild too.


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