Rebuilding '73 - '84 Silverado

[joesoares15]

I am looking to possibly purchase a '73 - '84 Silverado and rebuild. Wondering how feasible it is to drop a newer engine (fuel injected) and transmission in order for better mpg and more reliable so it can be an every day vehicle? Any thoughts on other common issues that may arise? Thank you

[mike357]

If you haven't bought one yet you could find an 87 which is already fuel injected. Otherwise it is not really hard to convert one. There are several ways you could go. You could get one of the after market FI systems that are out there. You can also use a factory system. Either way you will need an electric fuel pump and a O2 sensor bung.

 If you went with a factory system you will need to pick what you want, TBI, TPI, LT1 or a LS based system. The TBI, TPI and early LT1 will be an OBD system which will require the burning of chips mainly to get rid of the VATS if the donor was equipped with it or to take advantage of any motor mods. All of them will require either an original wiring harness to be modified or buying a aftermarket harness. Then you would need to hide the ECM inside the cab. If you went TPI or LT1 you can use a Corvette ECM which can be used in the engine bay.

 I would strongly discourage the LT1. I don't like the distributor design. I've had several vettes with LT1 and if the distributor gets wet, then its junk. The TBI and TPI would be the easiest. I've done a couple and went with an EBL ECM and it makes the ECM flashable like the LS based OBDII systems.

I have not done a LS swap, but you would need to have someone flash the ECM. It would also be the most labor intensive I believe because of the mods that would have to be made to mounts, and possibly the frame if you wanted A/C. As I said I have not done a LS swap, so hopefully someone who has will chime in and give you more accurate info on that.

I do think the LS swap would be more economical reliable to drive daily, but the most expensive to do.

If you go with the TBI/TPI get a FI block unless you don't mind drilling and tapping the block for a knock sensor.

As far as a tranny goes, a 700r4 would be the easiest. Any of the E trannys will need a controller, unless the system you choose has an PCM to control it. The EBL ECM I use will not control the E trans. I am about to do a TPI swap on an S10 and I will use the EBL and piggyback it to the original PCM to control the truck's original 4L60E.

[bake74]

     73-84 trucks have vastly different levels.  I would suggest deciding on what features you want on the truck first, so you know what year to get.  The engine/tranny swap will mostly be the same for any of those years.
    The trucks themselves have differences.  Look at the interiors for the different levels and features.  Do you want manual or power windows ?  Do you want cruise or not ?  etc,etc.

[Captkaos]

My 87 has a 03 6.0L/4L80E in it.  The whole process is documented right here: http://forum.73-87chevytrucks.com/smforum/index.php?topic=12120.0
Any model is feasible, pretty much the same technique applies.  I have one for my 89 Blazer also, in fact just about everything will have a LS.

[joesoares15]

Thank you for the information. I am looking at the earlier years preferably but again, not completely set in my ways. I was considering an LS based system for its mpg and reliability because I am looking to make this my only vehicle when this is all said and done. But more information on swapping in a LS would be great from someone who has done it. Thanks again.