96 5.7 Vortec Swap

[mtharmer]

Hi all,

I'm looking for some wisdom on an engine swap - I couldn't find any threads about this yet.

I am getting ready to swap out the dead 5.7 Vortec in my 96 K1500 for a rebuilt 350 from an '80 C/K1500. I've done plenty of work before, but never swapped an engine.

I'm low on funds and happened to have this rebuilt engine available, trying to find the least expensive option to swap and get it running again. Luckily the transmission is compatible and engine mounts line up so I should be able to drop right in.

My main concern for the swap at the moment is the intake. The 96 has CSFI while the '80 has a 4-barrel carb. To avoid having to mess around with the computer and/or fuel pump, I'd like to keep the intake from the 96. But, even if everything lines up, I am unsure what impact putting the newer intake with a different fuel system on an older model engine might have.

Any advice would be appreciated, and please let me know of any extra info you'd need.

Thanks in advance!

Mike

 

[HotWheelsBurban]

One major difference besides the fuel management/delivery system is the Vortec ignition uses a camshaft position sensor and a crankshaft position sensor to determine where the engine is in regards to the firing order. The crankshaft position sensor also is in the starting circuit somewhere, because if it's bad or the PCM (main computer that runs the engine) doesn't get a signal from it, the truck won't start.
I very much understand your financial situation, but the most trouble free way to do this is going to be replacing the engine in your truck, with another 5.7 Vortec, preferably a '96. There are so many variables and differences between the carbureted engine and the Vortec fuel injection system.... The swap you have the parts for('80 350 with a quadra jet) can be done, but it ain't gonna be easy...or cheap.

 

[mtharmer]

One major difference besides the fuel management/delivery system is the Vortec ignition uses a camshaft position sensor and a crankshaft position sensor to determine where the engine is in regards to the firing order. The crankshaft position sensor also is in the starting circuit somewhere, because if it's bad or the PCM (main computer that runs the engine) doesn't get a signal from it, the truck won't start.
I very much understand your financial situation, but the most trouble free way to do this is going to be replacing the engine in your truck, with another 5.7 Vortec, preferably a '96. There are so many variables and differences between the carbureted engine and the Vortec fuel injection system.... The swap you have the parts for('80 350 with a quadra jet) can be done, but it ain't gonna be easy...or cheap.

Thanks for the response! I had read something about differing cam lobes and cam/crank sensors, but I wasn't sure. Definitely started worrying me looking at all the sensors that the older engine doesn't have. That's unfortunate to hear but it does make sense.

The big pain here is that they only produced CSFI for one or two years in between TBI and MPFI, so like you said I'll have to essentially find a '96 to make sure it'll work properly.

Again much appreciated, I'll start the search and see what I can do!

Mike

 

[Schurkey]

The big pain here is that they only produced CSFI for one or two years in between TBI and MPFI, so like you said I'll have to essentially find a '96 to make sure it'll work properly.

'96--2000. Perhaps later than that for certain markets. I'd expect that any Vortec 5.7L engine from those years would drop in and be compatible.

The MPFI is an upgraded injector system that can be done to any of the Vortec 5.0 or 5.7L, and even the V6.

As said, the '80 engine will require heaps of work to make it compatible with your vehicle. NOT worth it.

 

[Erik the Awful]

You'd need Vortec heads, the Vortec intake, the Vortec timing cover w/ crank pickup, the Vortec water pump with the Vortec fan assembly. Ugh. I'm a cheapskate, and I'd try to find an engine at Pull-A-Part.