I finally have my 350 short block assembly together. Im going to put Vortec heads on it. Would I be better off paying the extra $ and get a new manifold to fit or should I get the ones drilled for pre-'86 intakes and run my factory GM Aluminum intake?
Good Guys Wear Bow-Ties
My buddy has a newer motor w/vortec heads, and he just drilled his old style Performer manifold to fit. I don't remember it clearly, but I do remember he did a ****ty job drilling the manifold. I'd call Edelbrock to be sure everything else is cool, like do the ports match good enough? Good luck
Buy the new intake, they are not expensive. The ports do not match up very well on the old intakes, and there is not much material where you have to drill the heads for the old style intake. Use the factory O-ring style Vortec intake gaskets.
Edelbrock sells a sweet Airgap manifold for the Vortec heads. They run between 150-200. Edelbrock also sells their multiport injection unit for the vortec heads. Might wanna check into that if you have the $$$. It is supposed to make some nice extra ponies.
I would have to say, get the Edelbrock Manifold. Check around for prices, I've purchased an Edelbrock #2116 intake manifold for only $135. All total I spent just over $700 for a pair of new Vortec heads, which included new head bolts, GM intake manifold gaskets, new intake mainifold bolts, new rocker arms, new Edelbrock intake manifold #2116, used valve covers, and new push rods.
Vortec heads are much nicer and worth the $$, but DO NOT work with non-vortec manifolds!! The manifold is not 'wide' enough at the runners to completely cover the intake ports in the head. I've been there and tried that. Buy a manifold that bolts on, and save the headaches and wasted time trying to make an older one fit. Good luck!!