Carburetors are dead! This mantra has been repeated over and over. Detroit hasn't built a carbureted vehicle for over 20 years,NASCAR has switched to EFI for the 2012 season and most cars featured in magazines like Car Craft and Hot Rod tend to more often be fuel injected. So why do I feel compelled to indulge in the shrinking subculture of carburetor building and tuning? Good question. In my younger days I remember looking on in befuddled amazement watching my uncles Bill and Al tune carbs in their respective shops and wanting to be like that someday. Technology evolved but those feeling did not, and as I delved deeper into the automotive hobby my tuning skills slowly began to take shape. But back to my original question, Why? With more and more kits available to retrofit carbureted vehicles to fuel injection from companies like MSD and FAST why not get with the times? Because upgrading to fuel injection is super expensive, like 2 grand expensive. If you added up the purchase price of the last four cars I bought it wouldn't equal 2 grand. So my plan is to screw together a budget fuel mixer for my 76 dodge powerwagon. And this fuel mixer doesn't rely on electronics,It simply uses rudimentary physics.
I purchased this Holley carb at a swap meet recently for $80. Swap meets are prime hunting grounds for unwanted Holleys. This model 3310 Holley it flows 750 CFM (cubic feet per minute) has vacuum secondaries and a manual choke. It even came with the crappy taiwan chrome fuel line! $50-$100 is pretty much the going rate for a rebuildable Holley.
My original plan was to buy a kit for this rebuild. But thanks to years of hoarding Holley parts I already had most of what was needed to bring my el cheapo carb back to life. Since most people don't have a milk crate full of Holley parts,a rebuild kit costs about $35 bucks. The crate also gave up a secondary diaphragm, which goes for about $10
Disassembly was the moment truth, Everything looked good,The only thing that concerned me was the plastic floats which would make me want to avoid ethanol. The floats went back into the carb but I may upgrade to brass floats at a later date. After disassembly the carb spent a night in a bath of Berrymans Chem dip to dissolve the grime and gunk.
The one trick part I splurged on was a QFT billet aluminum secondary metering plate for $36. Stock Holley metering plates are non-adjustable each plate is equivalent to a certin jet size, To change the fuel curve in the secondaries It's required to change plates or drill them out which can be a hassle.The QFT plate accepts holley screw-in jets,making it way more tunable.
I changed to a lighter vacuum secondary spring to make them open quicker.
I finished assembly with all the new parts, I also changed to an electric choke which is a little more user friendly than the manual one.Once It was installed I adjusted the idle mixture and float levels.
I was impressed with the initial test drive,It definitely feels stronger over the worn out carb it replaced and it even idles smoother. It currently has #71 jets in the primaries and #75 in the secondaries which seem a tad rich,So I may end up taking some jet out of it later. But with an investment of about $185 I'm one happy cheapskate.
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