Anyone have any idea how much work would be required to make a 7041540 run well on a manual trans 71 350? Owner says it was rebuilt by Ken or Mark. I'd love to put a Q-jet back on my 350 and get rid of the Holley, despite living in Bowling Green where Holley is headquartered. It is this carb: http://www.v8buick.com/showthread.php?300164-Qjet-for-455&p=2486123&posted=1#post2486123
The biggest differences are in the idle system, a 455 needs more air at idle than a 350. The 455 carburetor has idle bypass air passages. Mark or Ken could advise you further, maybe block the idle bypass? 455 carbs are great for a 350 with a big cam.
the idle air bypass holes can be blocked with some JB Weld or other epoxy in the bottom of the base plate. that is the first thing I would do. But it is also a question of the calibration of the 455 carburetor. It will be important to look at what's been done inside the carburetor and then match it to your 350. In stock form you might get away with just blocking the idle air bypass, but A modified carburetor is a bit of a different story.
I agree. If 350 is stock, it would not be the best way to go. Example, 7041540 woul have 73 jets, and 350 uses 68's. Plug the idle bypass air and downsize jets and it could be in the ballpark for you.
Good to know. I may buy it, swap base plates to my TV cable adapted throttle arm and run it on my car and rebuilt my old carb for the 350 as I don't want to have both of my cars broken at one time.