I have a '90 formula Firebird 305. engines tired. got a 96? vortec 305 (basically for free) i know mechanically its a direct swap minus the intake. will i need any thing else? a chip?
dmccain
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Chip could only help but it should run fine, and a lot stronger too, as a direct swap.
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cosmick
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The L30 Vortec 305 does not have the excellent heads, it just uses the newer intakes. And some of those L30 heads are swirl-port. You need to pull the heads, then pull the valves, if not swap on some milled 062s or 906s, or the heads off your old engine.
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They are pretty good for a 305. Not the same design as the L31 062/906 64cc Vortec heads but they did make 230HP on a 305 and have shown to be a pretty good cylinder head. Better than the 081s.. I don't know but much better than the TBI cylinder heads.
I'm not looking for a huge improvement just making sure everything will play nice. if a regular good running 305 fell in my lap I'd put that in but I happen to have the vortec one
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cosmick
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No, exact same ports and valves as pre-Vortec 305s. Remember, by '90 the LB9 was already at 230 HP, with more torque than the L30. The L30 heads gain you nothing, and cost you an intake manifold swap.
except bragging right for upgrading to a vortec engine 




