The Nostalgia Super Stock National Association and National Muscle Car Association uses these rules -

1.19 CARBURETOR
CARBURETOR (NSS CLASSES): All entries in the eliminator must be carbureted as outlined below. Carburetors must be of type and design as originally produced for a specific vehicle. Positioning of carburetors from factory mounting not a tech item (carburetors may be positioned facing forwards, backwards, or side mounted). Choke plate, choke shaft, choke linkage, and choke mechanism may be removed; choke horn removal permitted. The following carburetor combinations are allowed, regardless of year/make/model of entry:



•Buick 400-455; Single Carter, AFB, Edelbrock Performer or Q-Jet, inline 2x4 with Carters, AFBs or Edelbrock Performers.
Chevy 396,454 (F/X only): single 4 bbl with Carter AFB, Edelbrock Performer or Rochester.
•Chevy 348-409; Inline 2x4, inline 3x2 with Rochesters or single 4bbl with Carters, AFBs, Edelbrock Performers or Rochesters.
•Chevy 396-454; Single 4bbl with Rochester, Carter,AFB, Edelbrock Performers or Holley, Inline 2x4 with Carters, AFBs, Edelbrock Performers or Holleys, Inline 3x2 Holleys.
•Chrysler Hemi; Inline 2x4 or single 4bbl intake with Carters, AFBs, Edelbrock Performers, Holleys; or cross-ram 2x4 intake with Holleys.
•Chrysler Wedge; Inline or cross-ram 2x4 or single 4bbl intake with Carters, AFBs, or Edelbrock Performers.
•Ford; Inline 2x4 intakes, inline 3x2, or single 4bbl with Holleys.
•Pontiac; Inline 2x4 intakes or single 4bbl with Carters, AFBs, or Edelbrock Performers; or inline 3x2 with Rochesters.
•AMX 390— Single Carter AFB or Edelbrock Performer, Cross ram 2x4 bbl intakes with Holleys.

•Olds 400-455; 1x4 Q-Jet, inline with 3x2 Rochesters.
CARBURETOR (F/X CLASSES): Vehicles in these classes permitted the use of carburetors listed for NSS, or Holley up to 850 cfm in size (no Dominators). Aerosol carburetor(s) prohibited.

Multiple Carburetion Preferred

Racers with current legal National Muscle Car Association and Monster Mopar Dave Duell Classic single 4-bbl carburetor/intake manifold/vehicle combinations are encouraged to change to multiple carburetion. Racers with combinations currently under construction are also encouraged to use multiple carburetion.


1.20 FUEL INJECTION
FUEL INJECTION: Era-correct mechanical fuel injection permitted in F/X classes only.

1.21 INTAKE MANIFOLD
INTAKE MANIFOLD: In general, common commercial market cast units are preferred and required if available. Sheet metal units allowed only in AAA, AA and A/FX classes and only after inspection by the rules committee. Top of manifold lid may be modified and fabricated as necessary to accommodate carburetor placement.
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In general, there is no technical reason why a race car equipped with Holley carbs should necessarily be faster than one with Carter/Edelbrocks given identical engine/chassis/weight and so on.

Currently, there are some legal NSS cars with Indy intakes and Edelbrock carbs running in the 8's. In addition, there are many Indy/Carter or Edelbrock combinations which run in the 9's.