October Fast Talk with Jeff Smith – Carburetor Dilemmas on the Road

This road story happened 30 years ago, back when everybody ran a carburetor. I was on the road with my buddy Scott Sullivan in his Cheese Whiz orange ’55 Chevy. The plan was simply to prove that not all Pro Street cars were poseurs, by driving his Lingenfelter-built 496ci big-block Chevy from Dayton, Ohio to Los Angeles, California. We accomplished that feat, but not without lots of drama.

Among the more memorable problems we faced occurred rather early in the trip. Scott was running an 850cfm Holley carburetor, which he had a plating company change the hue of; going from the classic zinc dichromate to a rich deep black chrome. At first, the car ran fine, but as the trip progressed, the engine at cruise speed would occasionally stumble and run rough. Again at first, it would stumble and then regain its original smoothness.

This is Scott’s Cheese Whiz ’55 that he still owns. This was taken at the Grand National Roadster Show in Los Angeles in 2017. It looks as good today as it did 30 years ago!

By the fifth day of the trip (we weren’t in a hurry and the publishing company was paying the bills!), we were in Utah. Scott wanted to take photos of the ’55 out on the salt flats, but we were having trouble getting there. The ’55 had already broken a rocker stud which was easy to fix. Now it had developed a chronic roughness under cruise. If Scott stabbed the throttle the engine immediately responded and would haze the tires in Second gear, but its part-throttle behavior was getting worse.

Finally, we decided to pull over into a parking lot somewhere in Salt Lake City and I called a buddy who owned a carburetor shop. This was my first lesson in light-throttle idle circuit tuning. He told me to yank the primary metering block and blow out the idle circuit with compressed air. We found an emissions test shop in town and borrowed their compressed air and the engine immediately responded. I reset the idle mixture and we were off and running.

There’s a whole different story about cracked aluminum wheels, broken down on the side of a two-lane road in the middle of the Utah desert at night and Scott’s insistence on using too-small front tires to make the ’55 look mean, but I’ll save that experience for a later story. It involves a young car enthusiast in a tiny little town in Utah befriending us who went out of his way to help. Otherwise, we’d likely still be out there with a very dusty ’55 Chevy!

But back to our carburetor woes – once we repaired the wheel, the engine began to act up again. We later determined it was an errant piece of junk that was caught in one side of the two idle circuits on this Holley carburetor. By removing the idle mixture screw on the clogged side and blowing compressed air through it, the problem would disappear – but eventually return.

This quickly evolved into a procedure that Scott and I developed. Sometimes we could run through an entire tank of fuel before it would begin to run badly. Other times, we’d fill up and only get 20 miles and have to pull off the repair trick. Within a half day, we were practiced experts at the repair procedure.

30 years ago, there weren’t many options for changing the color of your carburetor. Thankfully these days, you can get a blacked out carb straight from Holley, thanks to their Hardcore Grey finish.

The engine would begin running rough and we’d start looking for a gas station. Back then, most stations still offered real automotive service with actual repair bays, so finding a station with easy access to compressed air was never difficult. Today, it would be a different story. As we approached the station, Scott would kill power to the electric fuel pump and the engine would generally die just as we were pulling in the drive.

Most of the time, the station was manned by a couple of high school guys who drove a performance car. The ’55 would roll in dead stick and both of us would immediately get out and pull the bra off the front of the car that was protecting the paint. I had the right tools already with me that I kept stashed on the floor behind the front seat. Scott would pull the air cleaner off and then leave to put gas in the tank while I immediately began removing the bowl screws to get at the primary metering block.

While all this was going on, the gas station guys would be salivating all over the car while monitoring this choreographed little pit stop. I would usually walk up to one of them and ask if they had an air hose and a nozzle I could borrow for two seconds. I’d learned that all I really needed to do was hit the main jet with the air and this would temporarily open the idle circuit, so I didn’t need to remove the idle mixture screw. One time one of the attendants asked me what we were doing and I explained it to him. He then said, “Man, this looked like a NASCAR pit stop!”

Looking back on this story, I called Scott to double check my memory and he said, “When I tell that story – I tell people that my buddy Jeff Smith just likes to get gasoline on his hands! That and that he can’t leave stuff alone…”

We finally made it to Los Angeles and even took the ’55 up to the drag strip for a nitrous-assisted pass that, with altitude-correction, was equal to a high-ten at 129 mph. That was despite the fact that the ’55 weighed somewhere in the neighborhood of 3,600 to 3,700 pounds. The NOS shot certainly helped.

After all of this, Scott then drove the Cheese Whiz back to Dayton and began working on his next automotive adventure. His latest hit is a ’54 Chevy cruiser with a killer LS-based Scoggin-Dickey 427 and a Tremec six-speed. This time the fuel and air mixing is managed by a Holley Dominator ECU instead of a carburetor. Maybe it’s time for an interstate reprise of that story. If so, I think we’ll keep Utah at arm’s length just so we don’t tempt fate.

This is Scott’s latest venture, a ’54 Chevy with all the subtle tricks and powered by a 427ci LS3-based engine with a Tremec six-speed. This time, Scott went with Holley EFI, so any cross-country adventures should keep the excitement contained to planned attractions along the way.

{ad: BLOCK}

About the author

Jeff Smith

Jeff Smith, a 35-year veteran of automotive journalism, comes to Power Automedia after serving as the senior technical editor at Car Craft magazine. An Iowa native, Smith served a variety of roles at Car Craft before moving to the senior editor role at Hot Rod and Chevy High Performance, and ultimately returning to Car Craft. An accomplished engine builder and technical expert, he will focus on the tech-heavy content that is the foundation of EngineLabs.
Read My Articles

Horsepower delivered to your inbox.

Build your own custom newsletter with the content you love from EngineLabs, directly to your inbox, absolutely FREE!

Free WordPress Themes
EngineLabs NEWSLETTER - SIGN UP FREE!

We will safeguard your e-mail and only send content you request.

EngineLabs

We'll send you raw engine tech articles, news, features, and videos every week from EngineLabs.

EngineLabs

EngineLabs NEWSLETTER - SIGN UP FREE!

We will safeguard your e-mail and only send content you request.

EngineLabs

Thank you for your subscription.

Subscribe to more FREE Online Magazines!

We think you might like...



Late Model LS Vehicles

Drag Racing

Performance Driving

EngineLabs

Thank you for your subscription.

Subscribe to more FREE Online Magazines!

We think you might like...

  • Late Model LS Vehicles
  • Drag Racing
  • Performance Driving

EngineLabs

Thank you for your subscription.

Thank you for your subscription.

EngineLabs

Thank you for your subscription.

Thank you for your subscription.

Loading