4.3L Vortec Rebuild

[SawDust{RM}]

Rebuilding a 4.3L with Vortec #OF3578xx ( 93-94 ) pre 96 Heads & Manifold I want to replace the Heads with 96 & newer Vortec heads last 3 of casting numbers 772/140/113 & use the newer 8 hole Intake that Match the Heads.

My question is will the newer heads fit the 93-94 block & can I use the same camshaft, & I need a new Harmonic Balancer (wasn't on the Engine) any comment on the interchangeability with any unit or is it year range specific. ( I have 3 donor boats for parts )

 

[GLENN M]

Re: 4.3L Vortec Rebuild

the heads are interchangable just use right manifold,cam is good,cant say for sure about balancer,cant remember witch blocks had balance shaft.

 

[proshadetree]

Re: 4.3L Vortec Rebuild

Older camshaft profile will not take advantage of these heads limiting potential. It will however work.

 

[Bondo]

Re: 4.3L Vortec Rebuild

My question is will the newer heads fit the 93-94 block & can I use the same camshaft, & I need a new Harmonic Balancer (wasn't on the Engine) any comment on the interchangeability with any unit or is it year range specific.

Ayuh,... Heads, 'n intake are No problem,... the cam will be just Fine...

The harmonic balancer Must match the block, by serial #s...
Crankshaft Balance changed a few times over the life of the 4.3s...

 

[SawDust{RM}]

Re: 4.3L Vortec Rebuild

After all considerations I'm buying a new 2010 Engine.
The Block I was going to use there were 3 different variations during that year, I did find a balancer to match, but for $200 more than buying the new heads, intake, balancer, rebuild of the block, gaskets etc I'm going with a new motor, & I've got plenty of hardware from 3 donor boats

 

[Alpheus]

Re: 4.3L Vortec Rebuild

As long as its a roller cam in the older block the cam parts numbers for the 96+ are the same. If your old heads have press in studs you will need to use the rocker pivots and nuts for the 96+ heads as they have threaded rocker studs. I just did this swap, check out my restoration thread...

 

[SawDust{RM}]

Re: 4.3L Vortec Rebuild

Thx Alpheus for the link