AA/SA @ Norwalk OH

Steve Hagberg · 06-22-2009, 05:29 PM

Jeff and David: Regarding the 3-bbl carb and intake, Chrysler completed the design modifications to the carb and 'short track' manifold and submitted them to NASCAR one week before the Firecracker 400 at Daytona in 1964. The combination was accepted by them and ran at that race. The manifold was the '043' magnesium version with the rear half of the plenum modified to accept the wide 3-bbl throttle blade. Les Norton runs this manifold on his car as it has been accepted by NHRA even though the carb has not been accepted! The interesting part of the story is that the Chrysler engineers spent a lot of time and money trying to get the 3-bbl to work, and even had to move the secondary boosters to correct the fuel distribution. Eventually they said it was worth 2% HP improvement, the same as they found in early testing with Hilborn fuel injection. The carb is a Holley model 3085A P/N 2536406 and used base plate gasket 2536411. One of these would be a rare find as it is not the same as the generic 3-bbl Holleys that were later sold over the counter. Anyway, it's not legal in stock, just an interesting story. By the way, I came about this information when a good friend let me look over an extensive collection of weekly engineering meeting minutes from late '63 to mid '64 by the group developing the A 864 engine program which included both the NASCAR engine and the Drag Race cross ram engine. Facinating reading. These guys were so far ahead of everyone else it was scary. Hollow stem valves, titanium retainers, a slew of light weight proposals including gun drilled cams, titanium wrist pins, Hilborns without conventional throttle blades. What we got was aluminum heads, oil and water pumps, mag intakes and more.

06-22-2009, 05:29 PM	#11
Steve Hagberg Junior Member Join Date: Dec 2007 Posts: 38 Likes: 0 Liked 0 Times in 0 Posts	Re: AA/SA @ Norwalk OH Jeff and David: Regarding the 3-bbl carb and intake, Chrysler completed the design modifications to the carb and 'short track' manifold and submitted them to NASCAR one week before the Firecracker 400 at Daytona in 1964. The combination was accepted by them and ran at that race. The manifold was the '043' magnesium version with the rear half of the plenum modified to accept the wide 3-bbl throttle blade. Les Norton runs this manifold on his car as it has been accepted by NHRA even though the carb has not been accepted! The interesting part of the story is that the Chrysler engineers spent a lot of time and money trying to get the 3-bbl to work, and even had to move the secondary boosters to correct the fuel distribution. Eventually they said it was worth 2% HP improvement, the same as they found in early testing with Hilborn fuel injection. The carb is a Holley model 3085A P/N 2536406 and used base plate gasket 2536411. One of these would be a rare find as it is not the same as the generic 3-bbl Holleys that were later sold over the counter. Anyway, it's not legal in stock, just an interesting story. By the way, I came about this information when a good friend let me look over an extensive collection of weekly engineering meeting minutes from late '63 to mid '64 by the group developing the A 864 engine program which included both the NASCAR engine and the Drag Race cross ram engine. Facinating reading. These guys were so far ahead of everyone else it was scary. Hollow stem valves, titanium retainers, a slew of light weight proposals including gun drilled cams, titanium wrist pins, Hilborns without conventional throttle blades. What we got was aluminum heads, oil and water pumps, mag intakes and more.