Picked up 800 CFM yesterday and am going to commence building it before spring. Besides Ruggles and Roe books, which I ordered, what else will I need to build this thing? In other words what should I order now? Is the Napa rebuild kit going to have most of what I need or is there a bunch of other stuff? (or is the Napa rebuild kit a bad idea???) Also I want to mount it to my Performer Intake and am wondering how to do the choke? Thanks for any input!!! Happy New Year!!! Clint
Hey Clint. good for you. Having fun with a Quadrajet. I would recommend getting a kit from either Cliffshighperformance.com (the guy that wrote the Qjet book) or from Greg Gessler. Both have good quality, complete kits for you. Cliff's kits include float and complete accelerator pump which you will need both. You need to check for any play on the bottom primary throttle shaft. It will probably need new bushings to keep from having any vacuum leaks. What is the number on the carb you are building? You may need to go to an electric choke if you are wanting to keep a working choke on the car.
depending on how heavy you're getting into it, to remove the idle tubes you'll need a pin punch, small hammer,wood screw and heat gun. a straight edge to check for warpage across the gasket surfaces. a pin vise and wire drills to resize the small circuits. before you do anything check the fuel inlet threads with the fitting removed, if they are stripped or damaged, you might want to consider another core. good luck
If you can rattle the primary throttle shaft & see gaps between the shaft and the holes in the base plate, you'll need the bushing kit. I'd do the leak test on the primary & secondary wells, and get some gray marine tex to plug the wells: http://www.marinetex.com/marinetexepoxyputty.html Since you've got a non-stock intake for your engine, start with the recipe in Chapter 6 of Cliff's book, and go from there. My setup is stock from 67, so I don't go too crazy with drilling out things...at least not yet.
Once you get the carb dialed in for your combination, the auto choke may work just fine. There are manual choke kits available, but the hassle typically makes people go back to the auto choke. Some of my previous posts for their adjustmants may help. Don't be afraid to ask questions. Ray
H A Guide to Understanding Your Riviera's 4MV 1971 GM 4MV Quadrajet Manual - GM Corp 1972 full Buick Chassis Manual - GM Corp Proper Carburetion Tune-up Methods for 69-71 Buick V8 Engines GM Corp Delco Qjet Manual & 71-73 SBs GM Corp sent in by Michele fm Vicenza I'm sure the above will help understand your carb. Also sending A PM link to download another step by step general rebuild guide thats not in the library.
Thanks everyone for the input!!! Cliff's hp kit looks like the way to go...will check out everything before I ordering to make sure I get all that I need, like the bushings if needed. I am fine with the electric choke as long as it works, looks like Cliff has that too for $45. I guess jets and metering rods will be stock, does anyone have experience with that at elevation in the 5280 ft range? I am here in the mile high city and want this to be right (running 10:1 compression and a GS-118 cam). Anyone around Denver have experience with QJet tuning? Big difference or no? Thanks again!!! Clint
I occasionally drive to Truckee California (6,000+ft) and find that at two or three jet/rod sizes bigger than stock this thing runs way too rich up there. It is fine (if maybe one size too rich) at sea level. I also have a 118 cam, and headers. Next time I open the carb (usually a once per generation thing for me) I'm going back to stock primary metering and will do any tuning with secondary rods. Cliff would probably tell you something similar; he's generally a proponent of leaving stock primary metering alone. Nearly forgot: with a 118 type cam you're running less idle vacuum (more like 15 or 16 inches versus 22 or so). You'll need a different (lower tension) primary metering rod spring than stock.
From the looks of your set up, it appears that the 10:1 compression may make up for the cam, allowing for similar manifold vacuum. At your altitude, the stock metering may work fine, as the increased altitude may compensate for the cam. I would try the factory metering at first, and see what you have. Ray
Thanks Man! That's great info for my set up. Hopefully this weekend I can at least find time to open up the carb and see how it looks. Best Clint
Make sure you know how to maintain part throttle mixtures. When jet size increases so must rod size by similar amounts. Stick with stock rods and jets and you'll have no trouble.
Thanks, seem's like there's no reason to go with anything but stock metering rods and jets at this elevation. Hopefully I will be able to get this thing apart and back together without a great amount of time. Need to find a place that can dunk it for me! Thanks again, Clint
Buy a couple of cans of Berryman B12 aerosal to clean it. You won't have to find anybody to dunk it for you.
Time for an update on this post. Last Sunday I finally had a reason to take down and open the carb as the choke rod had disconnected from the butterfly. Occasionally the tiny wire clip holding the rod in place wiggles off and is ingested (I think 4-speed cars probably do this more often than automatic equipped cars :Brow. If the rod disconnects from the fast idle hardware internally at the bottom of the carb the only fix is to remove the carb and put all this back together from unnatural angles and such. After 19 years of running 4 jet sizes (with properly chosen metering rods) richer than stock Stage 1 metering I installed stock Stage 1 primary metering (in my youthful exuberance I always thought the cam and headers deserved more primary fuel). OMG does this engine run stronger with leaner primary metering! I remember seeing a thread where Cliff had weighed in and recommended stock primary metering leaving performance tuning only with secondary rods. Umm...YEAH...that is great advice.
