Mention swapping out your four-barrel carburetor and thoughts instantly focus on a certain brand of four-barreled fuel-squirter. In reality, General Motors installed a gazillion more Rochester carburetors on their cars than the other brand. Due to a wide acceptance of the alternative design, which was easier to tune, and with a generally-better understanding of how they worked, many enthusiasts chose to remove their Quadrajet carbs.

Quadrajet carbs were used for the entire run of shark Corvettes, right up until the 1982 model year when the EFI era officially began for Corvette. There were some changes throughout the time when the Quadrajet carb was used and for those who chose to keep their Corvettes running on a Rochester, they benefitted from the brand’s reliability and fuel mileage.

Rochester engineers designed the carb so the engine would feed fuel from the two, smaller circuits toward the front of the carb. When more fuel was needed, the rearward circuit was engaged and regulated according to engine requirements.

For this Wednesday Rewind, we’re going to take a look back at a story we ran that helps identify some of the changes that occurred during Quadrajet production and how to identify a particular model of Q-jet. Many folks wrongfully think that “a Q-jet is a Q-jet is a Q-jet”, but they would be mistaken.

What secrets does this photo give away as to which Q-jet carb this might be? Check out the story to find out!

We’ve often wondered how many of these carbs are still out there in the wild and reliably running under those long, swoopy hoods of C3 Corvettes? Corvette owners have good reason to keep them running that way too. There’s no denying that today’s EFI systems bring a lot of benefits to the equation that a carburetor simply cannot, but when it comes to originality and performance in a ’68-’81 Corvette, it’s hard to beat a well-tuned Quadrajet.

Check out this story and you might just learn a few things about the lowly Q-jet that you might not have known previously. It’s information that bears repeating, and if you’re one of those folks who own a Corvette equipped with one of these carbs, you likely already know why so many Corvettes came from the factory with them.