4.3V6 to 350 engine swap

[Yo Dog]

I have a 95 chevy with the 4.3 and i am fixing to swap to a 350. I kwow all the brackets and trans will bolt right up. Will the computer work, just swap the chip, what about throttle bodies from a V6 to a V8 are they the same. Just anything to help me out that im forgeting. I have a complete 350 i am gona built maybe with a few extras not much, maybe a cam and headers. I would just like to aware of any problems i might run into.Thanks

[Puna]

I hope someone will answer you, I was thinking about this too for my 2000 Sil. Some how I think you will have to replace the computer, I was thinking about trying to grt the whole set up out of a wreck, engine,computer and what ever else.

[sc_customs]

I did a 4.3L V6 to a 4.8L V8 swap and it wasn't a walk in the park by any means.

A word of advice, make sure you've done ALL your homework before you start tearing your truck apart. Make sure that you meet all the emmissions requirements and criteria otherwise you will have a big mess on your hands (speaking from experience)

If you live in California it's even harder to get it through smog cuz of all the damn emmissions.

[Puna]

sc,
What all was involved, motor mounts, computer, will the stock exhaust, the cat part fit with shorty headers? Smog regulations here are REAL lax.
like i said i was thinking about getting what ever is needed out of a wreck and maybe some head work, small mileage type cam, nothing wild, I NEED more go then the 4.3 can provide but would still like to maintain a decent mpg, right now i get about 20 with the v-6 and think i can get at least close to the same with a v-8.

2000 Sil, 5 speed, reg cab,short bed,gibson side swept single exhaust, air raid filter, under drive pulleys.poweraid throttle body spacer

[broughy84]

4.3 to 5.7.....4.3 is the same identical motor except with the #3 &#4 cyl. shaved off. i don't know about motor mounts but this is what i do know:

1) You will need a bigger radiator (the v-6 rad. does not have enough cores to cool a SBC)

2) You will need to use the 5.7 injectors in the TBI system. This Throttle body is the same, but the injectors are different (the 5.7 likes to drink a little more)

3) I do believe that you are going to need the the chip out of a 350 TBI computer, for proper fuel/air mix.

4) The fan shrouds are different, the one for the 4.3 is longer than the 350, so you will need a new fanshroud.....psssst go to a junk yard....you'll find what you need.

[87shortbed]

i am currently doing a 89 4.3 swap for a 93 5.7 the trans bolted just fine with fly wheel had some troble with moter mounts had to weld then in(customer reqest) the intakes are comply different one is shorter abnd the other is longeer to more cylinders. the tbi unit had to be kept the same all electrical connectors fit just fine now i am going to look fo rthe righ chip to pput in the computer but dont know where to fine it please help/

[BlenderWizard]

The best i can offer is i swapped my 78's I-6 for a 305 and changed the tranny from a manual to an auto (and added power brakes, too). The main problem we ran into was locating the proper fan shroud to fit the v8. However, I know this is not quite the same swap