Edelbrock 340 heads with factory HP exhaust manifolds

[crackedback]

Mark it, 1"  or larger deep socket, lay it flat to make a radius relief and smack it to get some clearance.  Isn't going to hurt performance one bit.

Heat it up if you like when doing this.

These cars have horrible tolerance variances as well.  One car headers, exh fits fine, another hits everything under the sun.   They weren't built on a race car level jig.

[YellowThumper]

Out of curiosity, you could check with Edelbrock or research for dimensionally specs on their heads for comparison to factory port locations.

I suggest some creative dimpling of the header pipe. "Creative" enough to make clearance planned by exhaust supplier.

Small shim Brad mentioned is a good test also. For testing only, loosen pass mount and drop a washer or two as spacers. If this works, then fabricate a proper spacer.

[340Challman]

I'm completely onboard with the idea of putting a dimple in the pipe. My idea is to fill a sock with sand, slide it down in there and then lay some flat bar in the appropriate location and smack the hell out of it to create a flat spot. I've seen many factory flat spots in exhaust piping just for this reason. Thanks for all of the ideas. It kept me from being stuck in just one mode of thinking. I'll take pics of the finished product to show just how good or bad I did. 

[YellowThumper]

I'm completely onboard with the idea of putting a dimple in the pipe. My idea is to fill a sock with sand, slide it down in there and then lay some flat bar in the appropriate location and smack the hell out of it to create a flat spot. I've seen many factory flat spots in exhaust piping just for this reason. Thanks for all of the ideas. It kept me from being stuck in just one mode of thinking. I'll take pics of the finished product to show just how good or bad I did. 

Before pulling, draw solid markings on pipe for up and down clearance along with rotational centerline.