Project Sucker Punch Goes From Two-Fours To Three-Twos!

There has never been so many options for automotive enthusiasts as there are right now. Technology has not only brought amazing levels of performance and reliability to the table, but has also enhanced many vintage designs, making them considerations for those wanting to drive their rides for more than a quarter-mile at a time. Project Sucker Punch fits into that category.

sucker punch

Owner Aaron Hahn enjoys a good throttle-romp now and again, but mainly, the car was built to be a daily driver, and the Blueprint Engines 383 cubic-inch small-block that sits between the frame rails is well equipped to give him the best of both worlds. When Aaron first sought out what to put under the hood of his ’54 Chevy four-door, the stroked little small-block clearly rose to the occasion, so did the way the engine breathes.

Originally equipped with a four-barrel carb, Aaron soon doubled the number of barrels and distanced them from the engine via an Edelbrock E-Force Enforcer supercharger system which did a few things. Firstly, it boosted the output of the small-block with a 139.7 increase in horsepower at the wheels, and an increase of 108.0 lb-ft of torque.

The blower was a lot of fun, but the additional torque simply shredded those skinny tires. The tri-power keeps that vintage feel and brings great fuel mileage and throttle response, without all the tire smoke.

With the additional boost at lower rpm, the car took on a whole new attitude, and a romp on the throttle puts the car sideways with ease. Throttle response is instant, and care must be taken to keep the car in line, because the blower does far more than just obstruct your vision a little.

Synching With Uni-Syn

The trick to getting a smooth-running engine with multiple carbs is having them synched with each other. When using a progressive linkage like our system, you need not only make sure that the engine idles with all carbs synched together, but also that when the secondary carbs come in, they are also equalized with each other. The Uni-Syn tool has been an accepted way of tuning multiple carbs for decades. It doesn’t matter whether they’re on cars, bikes, boats or whatever, since the Uni-Syn deals directly with the vacuum signal.

Our set up is running all three idle circuits, so we needed to make sure that all three carbs were synched at idle. Then, we could hook up the linkage between the outer carbs and open them up slightly to ensure that they are synched with each other off idle. Keep in mind that with progressive linkage, the outer carbs will only synch with the center carb at idle and then not synch-up with the center carb again until WOT and we don’t use the Uni-Syn at WOT for obvious reasons.

The goal is to balance the fuel flow as well as possible throughout the entire operating range, but with a progressive linkage, this is impossible 100-percent of the time.

That brings us back to the original question of what to put under the hood. The supercharger is an excellent addition for increased torque, and a real attention-getter on cruise night. But it doesn’t work well with a hood on our ’54 unless you make headroom for the air filter.

While the bad-to-the-bone vintage vibe and high-tech reliability of the supercharger kept with our period-conscious build, we weren’t sure we wanted to make that modification to our ‘54’s lid.

Thankfully, Edelbrock has other options that are deeply dipped in the heritage of hot rodding, but uses modern technology to bring it forward to today’s reliability and street-ability. What hot rodder back in the day wouldn’t have loved a trio of two-barrel carbs perched atop their small-block Chevy V8? Edelbrock makes this a simplistic possibility today with their tri-power induction systems.

They are available for small-block Chevy (Gen I or Vortec head), Ford flathead, and Windsor engines. They are also available with two or six carburetor configurations, depending on the application. We opted for a trio of carbs to keep the number of barrels at a premium, while still enjoying the fuel-sipping tendencies of a single, two-barrel carb.

This is made possible thanks to Edelbrock’s progressive linkage, an original design of Vic Edelbrock Sr. The progressive nature of the linkage allows for operation of the center carb for normal driving and start-up. Then, when the loud pedal is pushed, the linkage is set to bring the other two carburetors on-line to feed additional fuel to the engine.

The system consists of a trio of Edelbrock 94 carbs and aluminum intake. We also opted for the spacers under the carbs to help keep heat at bay. Feeding off one carb means instant throttle response and great fuel mileage.

The fact that it all will fit under the hood of Sucker Punch means we can enjoy the kick-in-the-pants power that our engine has to offer, but we’ll also be able to enjoy a nice, clean engine bay should the weather turn sour. Less time cleaning means more time driving, which is why we started Sucker Punch in the first place!

Many ignition issues are blamed on carburetion, and when setting up a multi-carb system, you need to make sure your ignition is up to the task. Our distributor had a water intrusion issue at some point, and we upgraded to an MSD Pro Billet distributor. This would allow us to tune the timing for the specific needs of the induction.

Preparing For Tri-Power

Edelbrock’s “Model 94” style carburetor has been updated for use in multiple carb applications. For starters, they have extended throttle shafts with a knurled finish that allow for various linkage designs. The intake we used is the Edelbrock C-357-B style that is designed specifically for the Edelbrock E-Tec heads that we used on the top of our 383.

Because the carbs are similar to the original design of the vintage 94 carbs, they do not need much fuel pressure to run properly. Anything over 3 psi of fuel pressure can create problems for the fuel meters and create an over-rich running or flooding condition, which is not good for any engine. This necessitates using a fuel pressure regulator capable of regulating between 1-4 psi.

The Edelbrock progressive linkage is simple in its design, but allows for infinite adjustability. The Edelbrock 94 carbs' throttle shafts are generously long and knurled to allow for attaching a variety of linkages. We used a Lokar linkage to the throttle pedal.

Back in the day, 200 HP was king! Now, you make 350 just bolting parts together. The world has definitely changed so far as horsepower is concerned.              – Curt Hooker, Edelbrock

Just as adding carbs is a good way to increase the amount of fuel (and air) available to our engine, knowing our engine’s limitations and not reaching for the biggest and the baddest option is also a good way to avoid over-fueling. We asked Smitty Smith at Edelbrock about running only three carbs, “We have consumers that have these on small-block Chevys from 265 cu in up to 383 strokers, like this one. We even offer our X-1 intake for the SB Chevys that utilize six Model 94 carburetors with straight linkage on all six at once.”

Again, we wanted a daily driver with a vintage feel, so the tri-power would suit us just fine, thank you. For those wanting to go vintage and eyeing-up that full stack of 94s, we asked the folks at Edelbrock to help give us a guide to knowing if your engine is ready for a half-dozen dual-barrels. We checked in with Edelbrock’s long-time in-house carburetor guru, Curt Hooker. He’s in charge of their Dyno & Testing Division, so he’s seen how horsepower has evolved over the years.

sucker punch

One of the biggest issues when using any model 94 carb is excessive fuel pressure. No more than three PSI is recommended. We used this Edelbrock fuel pressure regulator, even with the mechanical fuel pump, to prevent excessive fueling.

Curt says, “It is hard to say when a three-deuce or a six-deuce is better. Back in the day, when these were the only carbs and manifold used, it made a difference. But with today’s intakes and carbs, neither one is better. The thing I usually say is ‘What look are you going for?’ Back in the day, 200 horsepower was king. Now, you make 350 just bolting parts together. The world has definitely changed so far as horsepower is concerned. With a carburetor, you are looking for around 1.5 inches of vacuum at max RPM at WOT. If you have more, then go ahead and put the six-carb unit on and floor it!”

We opted for the trio of 94s because it has that vintage feel while still allowing for our engine to run cleanly with great throttle response. The Edelbrock multi-carb systems that utilize their 94 carbs are designed to run off of each of the carbs’ idle circuits, so each carb does its part to feed the engine at idle, but as mentioned earlier, the bulk of the driving chores is handled by the center carb, until the throttle is opened up to employ the other two carbs. This helps with throttle response and fuel mileage, while providing the necessary fuel at WOT and at idle.

We have consumers that have these on small-block Chevys from 265 cu in up to 383 strokers, like this one. We even offer our X-1 intake for the SB Chevy’s that utilize 6-94 carburetors with straight linkage on all six at once. Smitty Smith, Edelbrock

The Bottom Line

Sucker Punch’s owner Aaron Hahn has had some time to put a few miles on the ’54, and he reports that he is very happy with the conversion, “The supercharger was nice and gave it more power, but was overkill for the car. The triple-deuce setup was easy to install and performs flawlessly. Having to feed only the center carb while driving around helps with fuel mileage, and the engine runs great and is very responsive.” Also contributing to the drivability of the engine is the fact that our engine now has excellent fuel atomization due to the increased vacuum signal present under the carbs.

The Edelbrock 94 carbs are updated to run today’s E10 fuels, come with .053-inch jets and 5.5 power valves, and are rated at 160 CFM. As mentioned, they are designed to always idle off all carbs, no matter if there’s two, three or six! All idle circuits must be synchronized to run evenly and cleanly at idle. This can be done by adjusting the linkage and idle circuits using a Uni-Syn, one of the best tools for synchronizing a multi-two-barreled induction system. Edelbrock offers the tool as part number 4025.

The nice thing about Edelbrock’s progressive linkage is that you can adjust the secondary carbs to come in according to the engine’s needs. The fully-knurled throttle shafts also allow for 100-percent adjustability of the shaft arms to keep all linkages synched throughout full swing to WOT. Once all carbs were tuned-in, the linkage screws were secured and the only thing left to do was drive it!

Stay tuned for our followup article with tuning help from a wide-band O2 sensor system and driver’s assessment from the triple deuce upgrade.

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About the author

Andrew Bolig

Andy has been intrigued by mechanical things all of his life and enjoys tinkering with cars of all makes and ages. Finding value in style points, he can appreciate cars of all power and performance levels. Andy is an avid railfan and gets his “high” by flying remote-controlled model airplanes when time permits. He keeps his feet firmly grounded by working on his two street rods and his supercharged C4 Corvette. Whether planes, trains, motorcycles, or automobiles, Andy has immersed himself in a world driven by internal combustion.
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