Editor’s Note: This article was published in Easyriders in 1995, but it’s still applicable today. At the time it covered the new Carl Morrow Typhoon billet Carburetor. Since then there has been some tweaking and Carl installed a Thunderjet on this Typhoon for the 5-Ball Racing Salt Torpedo we are building with a 135-inch JIMS twin cam and a JIMS heavy-duty 5-speed transmission.
Here’s the ThunderJet description from Zipper’s:
ThunderJet is a jet-able, externally mounted third fuel circuit that improves the performance of 2-circuit carbs such as the S&S Super. Unmodified, these carbs typically have a low speed, or intermediate, circuit that supplies fuel from idle to approximately 2500 rpm, at which point the carbs’ main jet circuit becomes active, delivering more fuel to the engine. These two circuits must then supply fuel for the rest of the rpm range.
The problem is: the remaining rpm range is too wide (typically 2500-6500 rpm) for only 2 circuits to handle efficiently. The tuner generally encounters problems jetting the carb to give good, crisp mid-range response and still have strong topend power. A compromise is the result. Back the main jet down, carburetion in the mid-range is good but top-end is lacking. Increase the main, top-end improves but now the mid-range is rich; flat spots or hesitation is encountered. The answer? ThunderJet from Zipper’s Performance!
Here’s the Typhoon Article from 1995:
Carl Morrow of Carl’s Speed Shop, previously located in Santa Fe Springs, California, had two missions in life. The first was to find ways to make Harley’s go faster, and put his riding son, Doug, in as many record books as possible. The second was to get the hell out of California! So, he’s moved his entire family (they all work with him in his shop) to the seaside community of Daytona Beach, Florida. Carl’s new shop was under construction during the 1995 Octoberfest; he’s opening for business in January. By the time of Daytona Bike Week 1996, his shop, located at 390 North Beach Street (a couple of blocks north of Daytona Harley) will be in full swing.
Performance is Carl’s passion. His latest accomplishment is the polished Typhoon billet carburetor, based on the slide-type CV and the early side bowl Linkerts for Sportsters and the very first Shovels. Of course the famous S.U. carb was an influence. Three classic carbs went into this design. The round slide in the front of the carburetor moves up and down with engine demand, keeping the velocity of the incoming air high, and allowing for extremely accurate fuel metering throughout the entire engine operating range.
The carb is simple, since the CV system allows Carl to do away with accelerator pump, idle circuits, and primary and secondary jets, and leaves owners with only one jet orfice to contend with. This jet is the brass fitting in the center of the table beneath the slide. It is penetrated by the jet needle, which is attached to the slide. As the slide lifts the needle from the jet, it allows more fuel into the venturi.
Since Bandit is a speed freak, we decided to take the plunge with his Dyna Glide. The Bandit Glide is a ’92, with dependable performance from Bartels’ Performance Products, and uses.080 shaved and ported heads, a BP 20 street, grunt cam, Bartels’ one-off pipes, Screamin’ Eagle Ignition and carb. The bike has always performed and held a constant 80 horses. It’s no slouch.
Carl went to work first removing the Screamin’ Eagle carb and Bartels’ manifold. He then bolted on his large plenum intake manifold loosely and installed the mounting strap to the center case bolt. Barnett cables are provided with the kit (push and pull, or just pull), but we chose to use Barnett braided cables. They work fine, but a slight modification had to be made to the cable end, which enters the guide at the billet throttle runner.
Their cable ends, which protect the branded material, are stronger and more substantial than stock. Consequently, they ran into one another at the guide. With a slight tweak on just one of the cable ends, they both slipped in without a problem. I suggested greasing the cable runners in the throttle body and next to the carb, and dripped some 30-weight down the cable–before final assembly–to ensure long life.
For a precision fit and a polished appearance, the entire carb is billet aluminum–even the cable linkage. Carl then installed the carb without the dome cover or the piston, installed the gas line, and turned on the gas. There is a small bridge under the piston and inside it is the main (the only jet). The float level transmits to this chamber and the gas level should be close to the top, approximately .060 to .080 below the jet orfice table–but not overflowing.
–Keith R. Ball
Editor, Easyriders Magazine
This is your built-in accelerator pump, choke system. That puddle of fuel is always at the ready when the engine demands it. If the level is improper, take the carb off the bike and dump the gas. Take the float bowl cover off by removing the four stainless steel Allen screws holding it.
Use caution not to tear the gasket. Locate the float and examine its operation. Corrections can be made by bending the stainless steel tang on the end of the float up for higher fuel level, or down for a lower fuel level. It is recommended to keep the level where specified; otherwise, the chance of flooding is increased. Replace the gasket and float cover. Tighten the screws snugly, but carefully, and avoid stripping threads.
With the float adjusted, Carl mounted the carb to the manifold with the piston and needle in place, and dome cap installed. There are only two adjustments to the Typhoon; the idle adjustment, and the main enrichener.
For idle adjustment, locate the throttle wheel attached to the throttle shaft at the rear of the carb. Just in front of this wheel, you’ll see a chrome thumb screw. If you screw it in clockwise, it will open the throttle disk, increasing the engine rpm and vice versa. It’s easy to adjust for cold idling and running.
The second adjustment is the main jet enrichment. The bolt and lock nut can be found at the very bottom of the carb body. To richen the overall mixture, release the lock nut and turn the adjustment bolt counterclockwise in small (one hex flat at a time) increments. To lean the mixture, turn the bolt clockwise. Make all adjustments slowly, then tighten down the lock nut snugly. Remember: Left is rich, right is lean. If at highway speeds the carb spits back, it’s running too lean.
Carl completed the assembly, took the Dyna for a ride, made minor adjustments, and turned it over to me. This Dyna’s always been a solid runner, and the song it sang was louder than ever. “I need forty-eight mph grunt to escape L.A. traffic,” Bandit said, “The grab at the low end has never been this strong. It’s instantaneous.”
Carl touted a 4- to 6-horsepower gain with the billet air cleaner or the nasty-looking velocity stack, respectively. But as all riders come to realize, the ideal grunt is in the seat of the pants. Bandit was so impressed, he rode directly across town 50 miles to Marty Ruthman’s Hi-Tech Custom Cycles in Van Nuys, California.
Marty builds fast bikes, He knows when a bike is performing, and he was almost launched off the rear of the seat when he hit second. Returning to the shop, Marty cleared his Dyno and said, “I’ve got to Dyno this puppy. It’s fast.”
To confirm the bike’s consistency, Marty ran the bike through its paces twice. With no modifications other than the installation of Carl’s Typhoon carb, it performed to 90 hp with 90 pounds of torque. Marty has since ordered a half dozen, and four are already out the door with similar results. “I mounted one on a guy’s bike and he was so pleased he brought me a box of imported cigars the next day. “Hell,” Marty said, “I don’t even smoke.” But the bikes with Carl’s carbs sure do.
–Article researched by Richard Kranzler
Bikernet Baggers
About Carl’s Speed Shop:
Dedicated to reliable performance since 1969, Carl’s Speed Shop has strived to achieve record setting levels of performance through extensive testing. Carl’s method of testing, however, is quite different from the ordinary. Many claims have been made about horsepower gains, flow bench numbers and Dyno results. Carl is a bit more real.
The Bonneville Salt Flats in Utah, Drag strips across the country, and of course, real highways and streets. You see, it takes reliable, useable horsepower to run well at the salt flats. Your motor must make horsepower over the entire range in order to pull the tall gearing required to go over 155 mph on a street bike. Since, at Bonneville, the throttle is wide open for extended periods of time, you get instant proof of what works and what doesn’t.
What Carl has learned at Bonneville applies rather well to high performance Harley street bikes. To supplement that program, we run many combinations at the drag strip to develop really great performance packages that mean real performance, not just numbers. You, our customer, reap the benefits of our years of experience, and you can bet that Carl’s Speed Shop can back up any product or service that we sell. Reliability in business is a key factor
Sources:
Carl’s Speed Shop
From Interstate I-4 Orlando Area East to 95 North on I-95 Exit US 92, International Speedway Blvd. East to Beach Street, Then Left {north) 5 Blocks on the left side.
From Interstate I-95 Exit on US 92, International Speedway Blvd. East to Beach Street Then Left on Beach Street, ( North ) 5 Blocks on The Left Side.
Zipper’s Performance
JIMS Machine
