I'm going to replace the carburetor on my deuce sedan,,it's been giving me problems and it's been rebuilt once and I just need to make the car more reliable. The engine is a 330 HP small block Chevy,,noting exotic and I do want a automatic choke. Should I use a 500 cfm or something larger? HRP
Sounds like a personal taste question....but we'll probably need to know more about the engine, car etc. Personally, I'd find a nice old Quadrajet and give it an overhaul and put it on there. I'm probably in the minority.
What he said ^ ! Q-Jets are good Carbs. It's just that most folks don't know what makes them click. There is a very good tech manual out that gives you more Info. than you can imagine,sorry I can't recall whom the author is,Google it I guess. So, Squirrel you are not alone on the Q-Jets.
I don't know a lot about carbs, but I do know that when Squirrel gives advice you are a fool not to take it!
When you say auto choke it makes me go to the Qjet then holley theres more of us than ya think squirrel M224SPEED -n- me
Dan, I would consider a 500-600 cfm AFB-Edlebrock. I've had good service out of them .....and they are easy to work on. What are you running now?
Amen Mr. Squirrel! Tho' I once knew a mech who called them 'Rotten-Chester-quadri-shits!' Not sure he read the manuals... I always liked the Carter type w/the metering rods, but the Rochesters did have tiny primaries and trap-door secondaries. Good mileage, good pickup.
I love a good quadrajet ( since those are technically off topic) Equally off topic The 625 street demon is really a neat carb. It's sort of like the love child of a quadrajet, thermalquad, and a little AFB and some Jetsons. The Jetsons part is easy to hide though. Amazing throttle response, easy to tune but the looks are no traditional at all. It's a demon but BG wasn't part of it.
What do you have now? Whats wrong with it? They can all be made to work...and they can all make you cuss when they dont. Electric choke, Vacuum Secondary should do all you want. I have an Edelbrock on the wrecker, it worked good out of the box on a more-or-less stock engine. But after a year or so of getting driven very little, I had to pull it apart and clean it good and put a kit in it. I blamed it on the crap we get for gas. Let me know if I can help.
I have had good luck with the Quadrajets in the past and am aware that they are basically trouble free if they are working properly but I am not a carburetor guy,,I can build a car but my carburetor prowess leaves much to be desired. The engine is a sbc..330 CI. The carburetor is a old manual choke Edelbrock,,it's been rebuilt once but still gives me trouble. I have a Summit Gift Certificate so I'm thinking about buying a new carburetor. HRP
This is strictly my 2 cents worth but, I spent many years working on carburetors and one thing is certain quadrajunks suck. They are hit or miss sometimes ya get a good one and most of the time ya don't. Danny go here. http://www.summitracing.com/popup/calcsandtools/cfm-calculator
They are complicated, they are infinitely tunable, and they are pretty damn good if they come from the right hands. Not everyone gets them.
Q-Jet gets my vote! I built one and run it on my Coupe and love it. If not, contact Jon "Carb King"-HAMB at "The Carb Shop" and have him pick and build you a Real Carter AFB for it. Don't cave in to buying another universal carb.
For the most part, If you can get a hold of the early ones you'll be good but the late versions are worthless.
Yep, some q jets suck! I like the older pontiac q jets, fuel inlet comes straight in the front of the Carb. I think they are from 1967 to 1971. Great running carbs and easy to modify for big cams. Second choice edelbrok but make sure you put an insulator under the Carb, suckers are notorious for boiling the fuel when hot and creating hot start problems.
HRP, best results I had with a carb on the 331 CI SBF in my model A was an Edelbrock 1405 (manual choke, 600 CFM) before I switched to a way OT Atomic EFI. I had a problem where, after tuning the carb to run well on the fuel it liked (pacific northwest) to back home, it wouldn't run. I put it back to stock settings. It makes me wonder what jets, rods and springs you have now. The new "reformulated" fuel sucks. I rely on the tuning "owners" manual. http://www.edelbrock.com/automotive_new/misc/tech_center/install/index.php Listed on that page, free PDF download. You can run through the troubleshooting tips in it. Best part about it is with the manual, you don't know how the carb works, if you follow the instructions. If you have eliminated ignition problems, vacuum leaks (including throttle shafts), and fuel supply issues, I would set the carb back to the factory base settings (jets, rods and springs) before replacing it. If it's still bad, those bits don't cost much. If you haven't eliminated the aforementioned other issues, please check, it sucks to install something only to have it not do what you expect. Edit: Oh yeah, FWIW, I like a well sorted Q Jet as well, but the manifold I wanted was square flange, and I didn't want to run an adapter.
Here is a good link for determinig cfm. I would run a 600, but all my engines spin up to 6500 rpm. http://www.summitracing.com/expertadviceandnews/calcsandtools/cfm-calculator
Merlin, how can you spend "years working on carburators" and come out of the experience CLUELESS? Anyone who shits on Quadrajets just doesn't know what they are doing. Litterly millions of them perform their function daily without a whimper. However, if your one of those individuals who sets the time on their wristwatch with a 2 lb hammer I understand. Frank
Put me on that short list of Q jet lovers, Oh Dan by the way you could give me or 31 vicky the certificate and well pick it up for you
Since this thread was placed in the "traditional" side, I fear to comment on the Q-Jet as I might raise the dander on the traditional police. Of course this eliminates MOST of the carbs suggested in this thread. Traditional carbs would include early Carter AFB's, Holley 4150/4160, Rochester 4-Jet, Carter WCFB's, Stromberg 4A, and Holley 2140/4000 units. A Carter 3720 AFB was factory equipment on the 340 HP 327, and has an automatic choke. It fits the traditional theme, and is a square-bore, so should fit the manifold used by the OP. Some of the other units suggested in this thread would require a different intake manifold. Jon.
Jon, how did you divine what intake manifold he has? If it's a Performer, or similar it will work with both spread and square bore carbs. The choke on the 3720 requires a heat tube, doesn't it?
The engine has a Edelbrock performer intake..2116 Problems,,Loading up..sometimes. Or I can be driving down the road and it acts like I have lost fire or run out of gas ,it sputters or floods,,it will cut off,,it will crank and run like a top for miles,then all of a sudden it will start acing up again if I stop quick or stab the gas pedal,,it's just not predictable. It might go a couple of weeks and no problems then all of a sudden here we go again. Wiring issues,,nope,I have traced every wire and there is no problems there. The gas tank is clean,the lines are clean,the filters are clean,the Holley fuel pump is clean. I have electronic ignition and a hot coil,,it all checks out fine. I run premium gas,,ethanol free 98% of the time. HRP
My truck did the same thing, until I snugged up the carb mount bolts and any hose clamps on my fuel lines. Seems to have worked... just throwing that out there.
Does it do this when hot, or cold? How does it act on hot restart after sitting maybe 10 mins? Really sounds like an ign problem to me.......
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