Well, having just bought a SB ProFlo4 I had to check mine out after seeing your post! Turns out Edelbrock may actually have to concede that this really is an issue that they have with these units. While it may just be possible to install the distributor without grinding I’ll definitely be tidying up the rough radius that they supplied mine with! Good time for me to do this is probably when I modify above the ports to allow the rocker covers to sit correctly - from what I’ve read this is an issue with the Super Victor style manifold. I’ve posted some images below,
1 - ProFlo4 manifold out of the box,
2 - For those that wish to compare the relative height difference between their existing combo and the ProFlo4 this photo shows the vertical height measurement from the top of a cast rocker cover rail to the very top of the throttle body - 6.340” (apologies for the poor focus)
3 - RPM Airgap for comparison and just to show that Edelbrock do know how to get it right
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