Credit portal




How much to swap an engine

how much to swap an engine

How to swap a Vortec 350 into a 4.3 S10/Sonoma

How to swap a Vortec 350 into a 4.3 S10/Sonoma

Doing a little write-up while it is fresh on my mind. This will be specific to a 2000-2003 s10 with the 0411 silver computer and 2wd. but alot of info will cross over into other years.

First, the engine:

You want a 1996-2003 350 out of a fullsize truck or an express/savanna van. If it is out of a 2500 or larger pickup, you will have to change the oil pan to the 1500. It will not clear the crossmember.

Things you want to do before install to the 350:

Well make sure it is a good engine. If it has too many miles on it I would rebuild it just for peace of mind, even if it is a good running motor. You do not want to be pulling this motor again in 20k miles.

AT THE VERY LEAST, change the intake gaskets.

I would also recommend changing the spider injector to the updated version.

Check the distributor gear for wear, and the shaft for side to side play.

Change the water pump. They are $40 for a brand new one. Again, peace of mind.

PAINT IT. This will make it look much much better when installed.

Things you will need before you start this:

Motor mounts.

Many different companies make them, including JTR and Current Performance. I went with the JTR.


4 options here. Heddman, Sanderson, Ebay stainless. all shorties. Or, if you dare(you will have to move your fuel lines), longtubes. I used the Heddmans. You have to specify bigger flanges with the heddmans. They come with 2".


Most people use the 1986-ish Corvette radiator. This requires cutting on the core support. And requires an adapter for the lower radiator hose. I used the stock 4.3 radiator. I figured if I have to cut, might as well make my stock one work. That way I was able to use the stock tranny cooler and oil cooler. There is other options that do not require cutting. Current Performance makes one that fits in the stock location. But its 500 bucks. I will post pics of the stock radiator frenched later in this post.


I used the

stock clutch fan that was on my 350. My 350 came out of a 1996 2500HD. You may want to go with an electric fan. I will be later when money allows.

Here are the electric fan options.

If you use the stock radiator(16x26 inches), a 2000-ish Dodge Intrepid fan will fit PERFECT. And will keep it cool. Also only pulls 14-16 amps. Also, a mid 90's Volvo fan will fit perfect. but pulls around 40-50 amps. You can also use an early-mid 90's Nissan Quest fan. Fits like stock and pulls only 20 amps.

If you go with the Corvette radiator(16x23 inches), your options change. A ford Taurus fan fits it perfect. The 1995 and below single fan dual speed ones. You can also mod the Nissan Quest fan and make it fit.

The biggest thing to remember here, is 1 or 2 aftermarket fans without a shroud WILL NOT COOL IT WITH AC. You have to run a shrouded setup to get maximum airflow over the radiator.

AC condenser.

No matter what, when you move the radiator forward, your stock condenser is not going to work anymore. Some people modify the hood latch bracket and move it to the front of the core support. Other option is the Current Performance one. It will fit behind the core support.


With a 2000 and up, you can use your factory 0411 computer. It will need to be reflashed. Many places do this. I tried Wait4me, and got screwed. It did not work. Engine only ran on 5 cyl. I now have a Current Performance computer in there and it runs great.

Companies that do this:


Current Performance

Black Bear Performance

And many others.


On the 2000-2003, use your 4.3 harness. You only have to add the 2 injector wires, add a 1 wire knock sensor, and separate the low side ground for the O2 sensors. I will get into wiring specifics later.

The stock 4.3 starter will work fine on either flexplate as long as the 5.7L was from a 1500 truck with 4L60e. My engine was from a 2500 with 4L80e so I could not use the flexplate. Again, the bolts on the 4.3 are metric and the 350 are not.

OK. next post will concern install. More to come.

Category: Forex

Similar articles: