I just aquired a holley carb with the list number 80457-5. My question is what, if anything, will I need to fit this to my 360 engine.

Thanks for any information.

 

I think that's an "S", and not a 5 at the end of the PN in your post. Hence, 80457-S which is a a 600 cfm vac secondary with electric choke.

You'll need a 4 bbl intake... either a stock 4 bbl intake or Edelbrock Performer PN 2105. Opt for an open element air cleaner and filter.. it's a very cheap upgrade and worth a few HP, even on a 2 bbl. A 4-hole phenolic spacer is worth some low and mid-range RPM torque. To make the best of the 4 bbl induction however, consider installing headers and dual exhaust system before the carb upgrad.e

The throttle linkage may need some mods. Mine had a bell crank mounted on the intake in between two rods on either side. I had some extra Mustang parts and installed a single rod between the carb and the bellcrank mounted on the firewall.

I suggest doing a carb rebuild to establish a known good baseline.

 

If you want real cheap install opt for a 2 to 4 carb adapter they sell them at carquest.