I am re-building a 1988 engine that uses a Weber 32/36 DGV. I noticed that the ports on the intake manifold are apprx 5 mm smaller in diameter than port openings on the head.

Would there be any performance loss or gain if intake ports are matched to the head? Or should I leave the manifold alone? Do the smaller intake runners/ports have a higher intake velocity producing more low-end power? Thanks,

 

If it's a std engine you're not going to notice any difference from port matching imo.
tabetha