swapping out 4.3 to 5.7

[Dayripper]

i have been reading the posts on here and find them very useful. but i have a few questions about this swap.

i have a 94 with a 4.3. 4l60E tbi
i am going to put in a 350 with a 700r4 and carb

my questions are
1. can i swap the belt drive system off the 4.3 over to the 5.7 along with the water pump
2. can i use the frame mounts from the donor truck, or do i have to have the one for a 94 chevy?
3. is the 700r4 the same length as the 4l60e?

the 350 come out of a RV and the trans come out of a 1/2 ton van with a 350 in front of it.


thanks for all the good advice i have found here.

 

[kevhill85]

i have been reading the posts on here and find them very useful. but i have a few questions about this swap.

i have a 94 with a 4.3. 4l60E tbi.
i am going to put in a 350 with a 700r4 and carb

my questions are
1. can i swap the belt drive system off the 4.3 over to the 5.7 along with the water pump >>> yes
2. can i use the frame mounts from the donor truck, or do i have to have the one for a 94 chevy? yes you can use mounts from 88 thru 94 350 trucks
3. is the 700r4 the same length as the 4l60e? Yes

the 350 come out of a RV and the trans come out of a 1/2 ton van with a 350 in front of it.


thanks for all the good advice i have found here.

I just done this same swap on my 1991 chevy

 

[Dayripper]

did every thing go smoothly? i plan on doing this swap in 1 day

 

[kevhill85]

did every thing go smoothly? i plan on doing this swap in 1 day

Yes, swap 4.3 to 350 motor mount was pain.

 

[Dayripper]

i may have to buy new mounts then. the mounts are from a 86. i was looking at some pics from auto zone. and the ones i have 4 holes while the ones for my year of truck have 3

 

[Dayripper]

will the y pipe for the 4.3 bolt up to the 5.7 manifolds? i am going to put true duels on with a cross over pipe. but its going to be a few weeks before i can do it

 

[Dayripper]

well i got the engine in but i have to change the block mounts. the older style mounts on the block are too tall!

 

[Dayripper]

ordered new mounts from GM. should be here in the next day or 2.

 

[Dayripper]

got the new engine block mounts in. had to run a wire to the fuel pump fuse. but the engine is sitting 2 inches to the passenger side of the truck.

is this where its supposed to be???????

 

[Dayripper]

well its all in and the new exhaust sounds great. now just to add some bling on the engine and a cold air intake system and im all done .. YAY ME!