[M&M CUSTOM]

I need to know what I can and cannot do with my wiring to retain the stock gauges when I swap the Olds 350 into my 1991 S-10.
The computer is going to be useless, I already know that, what do I do with that?
If I were to pull the computer and TBI out of a 88up C-10 with a Chevy 350 would I be able to use that on the Olds in this truck? as I don't have a carb for it yet.
To retain the gauge functions I would think I would only need to buy new sending units for the 2.5 originally in the truck.
To use the Chevy TBI unit I would have to fab a simple manifold adapter plate, and buy the sending units for the chevy 350.
The computer is where I have the LEAST knowledge. Would this TBI computer and harness out of a full size truck work in this truck and be compatible with the cab harness and connector, or should I gut a fullsize truck completely for the complete wiring harness.
MATT@M&M CUSTOM

[M&M CUSTOM]

UPDATE:
I am able to gut a 1991 K-2500 with a TBI 350, its my dads old truck and I helped my sister get rid of it before the city she lived in impounded it as she blew the bottom half by not putting oil in it.
The guy I had pick it up wanted it for the drivetrain parts for his 95. So I can get this project phase out of the way.
I just still need to know about the harness though.
This sure beats the $300 for a new carb.

[NorthStar]

This sounds like a cool project not only will the motor not be another belly button small block but it will be computer controlled too.

The distributor could be a problem.

The ECM/PCM uses its own water temp sensor and oil pressure sensor is part of the fuel pump relay circuit and runs gauge.
I think those are only gauges you would be concerned with so I wouldnt go tearing the entire harness out of the S-10.

Im not 100% sure of this but you might be able to plug in the 350 truck computer to youre existing harness.

There are two different types of engine computers for 350 TBI.
ECM (black connectors) which has a seperate knock sensor module and PCM (brown connectors) which has a built in knock module, they wont interchange.

Sensors you will need:

distributor
oil pressure
coolant temp sender (for gauge)
coolant temp sensor (for computer)
knock sensor
EGR controller
MAP sensor
throttle body (many different ones)
throttle position sensor (theres two styles of connectors)
idle air controller
EGR valve
O2 sensor
knock module (maybe, depending on which computer you get)


Its easy to get fooled when buying a junkyard throttle body so make sure you know it came from a 350 tbi.


You can use this to check you existing sensors/sending units and see if any of them will work.
Standard Ignition

[M&M CUSTOM]

I already made up my mind to do this injection project.

I just won an Ebay auction for a TBI to 4 barrel intake manifold adaptor.

http://cgi.ebay.com/ebaymotors/ws/eB...tem=2436321956

And I found this thing this morning just minutes before I went to the biggest boneyard in the area, couldn't find anything like it there though.
When the wife and I got back I checked the auction ending time and had 11 minutes to go, the wonderful wife that I have, she said to go ahead.
And as far as the stuff on the engine in the K-2500, I will pull all the sensors that it has, buy new replacements and install them on the Olds 350.
Matt

[jrhoss]

have you test fit the engine yet, because that olds engine is pretty wide especialy for an s 10

[M&M CUSTOM]

I haven't test fit the engine yet, but am not in a hurry to do so with a 650 pound engine either, the first thing I thought of when deciding to use this engine was to retain the stock manifolds.
First, they were designed by GM to flow well enough for a diesel with one piped into the other, then they flowed out the passenger side manifold in a single pipe to the end of the car.
If this was good enough for GM, then why cant I use the same manifolds and run a full length dual exhaust, I have never heard anyone say the factory did anything right when it came to performance, almost everything can be improved.
I bought an oil pan, valve covers, water pump pulley, exhaust manifolds, air cleaner lid, and motor mounts from the junkyard the week before last and will mock them up with 1/4 inch bolts welded to a 1/2 inch welded angle steel to replicate the exact dimensions of the complete engine, but with one major advantage.
I will be using this mock-up engine for test fitting purposes rather than having a perfectly good 650 pound engine swinging and banging around, and besides that little safety factor, I can't get the hoist in the area where the truck is located as there is too much other stuff in the way- I am saving a lot of room with this truck being located sideways at the back of my carport.
When I get the mock engine put together I will post a picture of it in my album here.
Matt

[itsalryt]

I just joined this forum and saw your post. I'm doing something similar. Any advice?

[joe_padavano]

The one trick for the Olds distributor is to use the computer controlled HEI from an Olds 307. Change the plug on the TBI harness to match and the pin functions on the HEI module are the same. The stock TBI PROM for a 5.7 will be close, but if that particular PROM has VATS you'll need to bypass it.

[ChevyTruckGuy]

You should be able to find a swap kit out there for this project! I have seen them! might want to try one of the S10 sites! Also here are the tbi site ever one uses!
www.ronfrancis.com www.thirdgen.org www.fullsizechevy.com www.moates.net

Craig

[against all odds]

These guys can probably help you with everything or at the very least answer all your questions:

http://howellefi.com/


My other car is TBI and i'm really tempted to convert to TBI on the small block because i love the crisp fast startup in any weather and no stumbling, no flat-spot driveability, but i probably won't because sticking with carbs is cheaper. Also, to be fair my carbed motor starts pretty fast in the cold.

[EagleMark]

Originally Posted by ChevyTruckGuy

You should be able to find a swap kit out there for this project! I have seen them! might want to try one of the S10 sites! Also here are the tbi site ever one uses!
www.ronfrancis.com www.thirdgen.org www.fullsizechevy.com www.moates.net

Craig

You forgot one!

***************************

Howell makes an excellent kit! But you can also do it yourself with all OEM and junk yard parts for cheap! Biggest expense is an aftermarket harness for around $300. I pull one from a car or truck at junkyard for $20. Then put about 4 hours into it...

The Howell systems are GM 1227747 ECM with very minor changes to match the engine they are going into. All wiring diagrams, malfunction codes, chip/bin files and the TunerPro Definition files to do it yourself are here:
*************************************

[itsalryt]

Thanks for the quick replies. In my basic research for this swap, (TBI 4.3 to TBI 350) I've been told that the computer in my 91 Jimmy will work with the 350 by installing a chip to convert from the V6 to the V8. How accurate is that advice?

[EagleMark]

Could be if your ECM has a Memcal chip. It would have the limp home chip and knock module in it. So yes change the Memcal.

If it is a regular chip then yes it would run with new chip but limp home mode would probably not run a V8. On those the knock module is called an ESC and mounted on engine.

What is the number of your ECM?

[joe_padavano]

Originally Posted by itsalryt

Thanks for the quick replies. In my basic research for this swap, (TBI 4.3 to TBI 350) I've been told that the computer in my 91 Jimmy will work with the 350 by installing a chip to convert from the V6 to the V8. How accurate is that advice?

That is correct, but you need the chip from the same number ECU. GM used a number of different ECUs on the TBI motors. You might be better off using the ECU from the 88 donor truck, since you know that will be compatible with the 350 PROM.