Pontiacs are torque producers and need a fair bit of work and $$ put into them to spin them up to where the sbc can go easily..

It's your choice, but a suggestion before going down that road, try a stock intake or ebrock performer, you may be happy with outcome and you can usually pick up a used performer for $75.00. If you aren't happy you will get your money back less your time..

The RPM manifold is not giving you the full advantage of the low grunt you motor has in it...