On the outside, it’s Genuine 97 all the way. But on the inside, it’s the ultimate 750cfm hot rod Tri-Power. Totally new 97s with improved fuel circuits, ported distributor vacuum and a whole lot more. Add our chrome progressive linkage and polished 3-into-1 fuel line (SBC only)  and you’re looking at old school carburetion with next level performance and drivability.

Designed as a Tri-power

Unlike the original 97, the BIG97 was designed from the start to be used in a Tri-Power – a central primary carb plus two less sophisticated secondaries on a progressive linkage. Cruise economically on the center Primary, then punch in the Secondaries when you step on the gas. It’s the perfect bolt-on for your small block Chevy, Ford or other overhead valve motor.

You can read all about BIG97 Primary carbs here. BIG97 secondary carbs have no power valve or accelerator pump circuits, but keep chokes, idle and transition circuits for steady idle and good low throttle manners. Dummy accelerator pumps retain the classic 97 look.

Ported distributor vacuum on the BIG97 Primary connects to your vacuum advance distributor to improve combustion efficiency in cruising mode. You’ll run smoother and cooler, with more torque and better fuel mileage.

On these models, the carburetor body castings are painted with black lacquer before assembly with all threads recapped and fuel passages cleaned. The brass plugs, screws and S-jet are chromed, and the stainless steel linkage and springs are polished.

Runs out of the box
It comes ready to run, too, though a wide range of jets and power valves are available to suit individual applications. Every BIG97 comes with full installation instructions and you can find more help on our Tech Center.