How to rebuild a Rochester Quadrajet 4MV carburetor
(Add text) |
(Add text, link; minor format) |
||
| Line 389: | Line 389: | ||
==Casting smoothing== | ==Casting smoothing== | ||
Generally speaking, reworking the castings of a carb without any empirical way of measuring changes is like porting a cylinder head without a flow bench. What looks good may in fact be the exact opposite of what the carb needs, and without knowing what is happening as you make changes, the results can be worse than if you had done nothing at all, so if you decide to do anything, do not change the shapes, angles of attack, or any other parameter that was a designed-in feature of the carb. Keep things to a minimum- smoothing obvious flaws and mismatches, and leave the rest alone. | Generally speaking, reworking the castings of a carb without any empirical way of measuring changes is like porting a cylinder head without a flow bench. What looks good may in fact be the exact opposite of what the carb needs, and without knowing what is happening as you make changes, the results can be worse than if you had done nothing at all, so if you decide to do anything, do not change the shapes, angles of attack, or any other parameter that was a designed-in feature of the carb. Keep things to a minimum- smoothing obvious flaws and mismatches, and leave the rest alone. | ||
| + | |||
| + | If you are a "burr freak", [http://www.cratex.com/rubpoint.htm Cratex points] can be carefully used in a Dremel tool. Using them will provide the very highest finish of any "Dremel-type" points, especially on curved and/or intricate castings. Some come mounted, others can be mounted on a small arbor w/screw (you know the arbors- like used for the small cutting discs). | ||
| + | |||
| + | I would avoid using mounted stones altogether- they will leave a rougher than stock finish, and generally are not as precise as I believe is needed for that type of work. | ||
| + | |||
| + | There are paper sanding discs (400-600 grit and finer) that are fine enough; backing them with a round piece of plastic cut from a coffee can lid can give enough backing to allow smoothing and polishing, when mounted on a small arbor. | ||
===Primary=== | ===Primary=== | ||
| Line 403: | Line 409: | ||
Lastly, there's a lot more to be had in setting up the APT, idle/transition and main circuits, and the secondary tip-in than there is in dickering with the castings. | Lastly, there's a lot more to be had in setting up the APT, idle/transition and main circuits, and the secondary tip-in than there is in dickering with the castings. | ||
| − | + | ==Quadrajet tuning and repair parts== | |
*[http://www.cliffshighperformance.com/index.html Cliff's High Performance] | *[http://www.cliffshighperformance.com/index.html Cliff's High Performance] | ||
*[http://quadrajetparts.com/index.php QuadrajetParts.com] | *[http://quadrajetparts.com/index.php QuadrajetParts.com] | ||
Your Privacy Choices