Alignment issue with Edlebrock manifold on SBC w/ Vortec

[David67]

We have an Edlebrock Performer manifold for a SBC 350 cid with Vortec heads. The manifold bolts have the correct threads for the Vortec heads, BUT the holes in the manifold are a bigger size, so the manifold can shift front-to-back a little.

Should we just center on the bolt holes or is there some trick to ensuring the airflow paths are smooth at the interface? It seems a little misalignment of intake manifold ports with intact head ports would be a VERY bad thing...

Thanks.

Mark

[RustyParts]

You can use a pin punch with a 3/8" shank to align the intake to the bolt hole. Insert the pin punch through the intake hole and into the threaded hole on the head until the tapered end of the punch snugs up on the intake hole.

[70Custom10Nut]

Following Rusty Parts' advice, just make sure you cinch it down a little at a time, alternating the tightening, to ensure that it stays centered

[67Dad]

Thanks RustyParts and 70Custom10Nut. We also found out that Edlebrock has some special bolts...5/16 threads on bottom but 3/8 non-threaded shoulders. (Still not sure just why they would do something like this...interchangeability perhaps?) Thanks again.