I was just wondering if anyone out there has ported/polished their stock plenum as opposed to buying an aftermarket one. I have had this done on cars in the past with good success and there is a shop here in town that does it but I wanted to get some opinions before I did. If you have done it, anything I ought to know? Thanks

 

Not gonna work... the metal is too thin. Also you would still not eliminate one of the things that causes the most airflow disturbance; the 6 bolt supports holding the plenum on...

 

And the taper from back to front that restricts airflow to the front cylinders.