Changing my 4.3 over to the 350 in my 89'!...

[hooter992]

In the process of changing my 4.3 liter over to the 5.7 liter (350 for those of us metrically em-paired lol ) got the mounts out today and installed the V-8 lower mounts...(it can be done with out pulling the springs and without cutting the truck just in case you guys wondered!) now for the good stuff.. I have a V-8 radiator (new) V-8 fan shroud (new) what else will I encounter? I have the complete engine from a 89 surburban and my trucks a 89 1500 so I think I'm about to top the hill and ...the rest should be down hill...any tips? thanks

Hooter992

[chevy4x4trucks]

Looks like you've got most of it covered.  What type of tranny is in the truck now?  You may want something that's a bit sturdier since you'll be pumping quite a bit more power through it.

[textruckr]

Don't forget to get the ECM from behind the glovebox.  At the least you will need the EPROM to change out to the ECM in your truck.  The ECM will not be able to correctly time the engine or pulse the injectors as it is currently programmed for the V-6.  It will also change your shift points on the transmission (if auto).

Check all of the other connections too (temp feed, knock sensor, O2 sensor, MAP, etc) to make sure that they are located fairly close to where they were on the 4.3, otherwise you may have to change out the harness in some applications.

The 4L60 is different between the 4.3 and the 5.7 - you may want to talk to the trans shop to find out if the bellhousing will match up.  I think that there is a different sun gear and fewer clutch discs in the 3-4 pack, but I am not certain - just know that early versions of the 4L60 are different.

[hooter992]

5.7 liter is in! It did bolt up to the trans and everything worked except for the motor mounts, radiator, and fan shroud! Go figure!