With all respect to those who have posted that have had success with the clones:

Comparing something new to something needing work will normally mean the something new works better.

However, comparing a clone on a SBC to a properly functioning Q-Jet would result in:

(A) fuel economy of about 10~15 percent less for the clone
(B) low RPM torque of maybe 5~10 percent less for the clone
(C) more difficult hot starts for the clone
(D) no improvement in high end HP for the clone

Remember that the Q-Jet is a 750 CFM carburetor (150P/variable 600S). The 600 clone is 250P/variable 375S (no, this is NOT a misprint!).

Running the clone through a square-bore -> spreadbore adapter (not changing the intake) reduces the clone to a 525 CFM (150P/variable 375S).

However, the clone is convenient, if you don't object to the loss in performance.

Jon.



Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
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