Lou C
Supreme Mariner
- Joined
- Nov 10, 2002
- Messages
- 13,024
You are right about the metal tube it just loops into the exhaust crossover passage. The newer Vortec style engines (1996 and newer) do not use an exhaust crossover and have to use an electric choke. The newer engines do have 2 advantages over the old style V6’s we both have:
1) the Vortec cyl heads give 20 more hp
2) the post ‘94/95 engines have a balance shaft just above the camshaft that cancels out the vibrations caused by the uneven firing pulses of the 90* V6. GM did this to save money and was able to use the same tooling they used for a V6 as for their V8s. So the 4.3 is just a 5.7 with 2 cyls removed or 3/4 of a 5.7. The crankshaft has split rod bearing journals to even out the firing pulses.
and, if you use a Vortec engine and add an Edelbrock dual plane 4 bbl manifold it adds 18 more hp over the stock 4 bbl cast iron intake.
so here are the power ratings:
Pre Vortec 2 bbl 175 hp
Pre Vortec 4 bbl 205 hp
the Vortec heads add 20 more for 195 and 225,
and if you add the 4 bbl Edelbrock alu manifold it goes to 243....
1) the Vortec cyl heads give 20 more hp
2) the post ‘94/95 engines have a balance shaft just above the camshaft that cancels out the vibrations caused by the uneven firing pulses of the 90* V6. GM did this to save money and was able to use the same tooling they used for a V6 as for their V8s. So the 4.3 is just a 5.7 with 2 cyls removed or 3/4 of a 5.7. The crankshaft has split rod bearing journals to even out the firing pulses.
and, if you use a Vortec engine and add an Edelbrock dual plane 4 bbl manifold it adds 18 more hp over the stock 4 bbl cast iron intake.
so here are the power ratings:
Pre Vortec 2 bbl 175 hp
Pre Vortec 4 bbl 205 hp
the Vortec heads add 20 more for 195 and 225,
and if you add the 4 bbl Edelbrock alu manifold it goes to 243....