Originally Posted by JOHNSHENOUDA
I was installing a new Edelbrock intake manifold on a sbc350. Out of the 12 bolts the four in the center made me crazy. All of the others drop right in. If I attempt to install only the inside four then it does not seat and the rest wont line up. After fifty or so attempts I gave up. I screwed the bolts into all of the 12 holes without the manifold and they thread real nice. Being at the end of my hoes I decided to just use the outside eight. Last night I fired her up for the first time. I was orgasmic! My friend noticed the holes on the inside four are empty and he believes that oil will eventually come out of there. after several attempts to drop in the inside four he also gave up. The bolts all go in on an angle. So I definitely don't need one of those thread hole kits for the bolts that shoot straight down. Why in the world wont they start? If I leave them as is will oil come out? I really don't want to remove the carb,alternator,a/c compressor, all the wiring, the distributor, all of the plumbing, and the sensors to get at the manifold so that I can re-seat it again only to find that it won't seat with the four inside bolts. I mean it would not work the first fifty or so times so why will it work now. Maybe if i grind down the sides of the end of the bolt it will force itself in?
Sounds like the manifold wasn't drilled right. This is seen much more often on offshore intakes than those made by Edelbrock.
Are you sure the intake gasket isn't the problem? If not, you can grind the intake bolt holes as needed to get the bolts to line up- just don't cross thread them!
One more thing- be sure the bolts aren't too long, else there are a couple that can hit the pushrod. IIRC, intake manifold bolts for cylinders 4 and 5 should not use 1-1/2” bolts, use 1-1/4” at the longest.