Designed for street 1987-94 Chevrolet 4.3L V6 with factory Throttle Body injection. The Performer 4.3L intake manifold provides outstanding throttle response and torque increases from idle to 5500 rpm. A computer chip is available at no charge and is street legal for 4.3L trucks. Return the postage paid card that comes with the manifold to receive the chip. Manifold and chip provides a 6/10 second gain from 10-70mph. Not for vehicles with flash memory computer. These are most 1994 and later 4.3L TBI V6 equipped vehicles. Flash memory ECM is located underhood. Will not fit 1986-89 Astro/Safari Vans, will fit 1990-95 Astro/Safari Vans.