I still am tuning my engine engine with the D452's and the front tubes are getting dull.I will be jetting up this season because know I am still too lean just by reading the plugs.I think If I had it fat enough at first my tubes would still be shiny as the other tubes
Gus

64 Plymouth Savoy
493 Indy EZ's by Nick at Compu-Flow
5-Speed Richmond faceplate Liberty box
Dana 60