1995-2007 Vortec intake manifolds

[truckster]

The poppet valves can't be tuned. I understand later model L31 Vortecs used an updated spider that had true multipoint injectors. I don't know if they're still available.

[Tom]

Originally Posted by truckster

The poppet valves can't be tuned. I understand later model L31 Vortecs used an updated spider that had true multipoint injectors. I don't know if they're still available.

96-2000 was vortec with poppet injectors. They all came poppet from the factory. Chevy release an updated MPI setup that turns the poppets into 8 mini injectors. They can be retrofitted to any vortec small block.

None can be tuned for more flow. That requires a marine intake manifold that uses normal injectors.