I'm with Charrlie on this too. Ran the 500 on my cars,3 of them both on and off the track.
Though I am not a fan of Holley,some run the 390. I did and was not satisfied,switched to the 500.
On my last Slant I ran a 600 Edelbrock because I had one. Worked really well but I prefer the 500 only because of better throttle response.
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