'57 4520 fi

[Wayne G.]

Re: The "Cadillac" of air meters.....

John, The polishing took place years ago and wasn't up to the perfection you can accomplish today. The ribs were pretty much left alone, the sides and ends had some sand cast appearance removed. I used a couple of different media blast methods, walnut shells and soda with real good results and finished it with an acid cleaning. It looks pretty good, but I bet if i could find a mint original I'd sure pick it up! Thanks Wayne

[John D.]

Re: The "Cadillac" of air meters.....

HI Wayne, Here's another little know fact about the '4520 FI unit. Did you know there were three variations of '4520 plenums?
The first one was a carry over from the '4360 unit. Remember RP didn't waste any castings. So the first '4520 plenum had a 1/8" pipe hole in the rather thin casting.
The casting number was partially ground down and new numbers hand stamped.
The 2nd '4520 plenum looked the same as the first except the 1/8" pipe fitting (in front of the plenum) went thru a heavy boss.
The 3rd generation plenum had no winter leaf snowflake on it and looked the same as the '4800 plenum except for the nozzle block holes.