Didn't realize it until today, but Holley actually holds training classes on installing, setting up, and tuning carburetors. They bulk of their classes are geared toward learning how to install and tune electronic fuel injection systems. Stop the hissing, I know none of you are interested in that electronic mumbo jumbo. Anyway, they also host a few training classes on the art of tuning a carburetor properly. (Applause here) The classes are held in Bowling Green Ky at the Corvette Museum and Beech Bend Raceway is nearby. https://www.holley.com/blog/post/carburetor_101_training_class_dates_released_for_2023/ CARBURETOR 101 The Holley model 4150 and 4160 platforms have been in production since 1956, first debuting on the 312ci V8 in the Ford Thunderbird, and over the years since they have been used as OEM carburetors and have found wide acceptance in the aftermarket. Nearly every form of performance automotive and marine application one can think of has relied on a Holley carburetor to deliver power reliably for years on end. Don't just guess at how the carburetor works or adjust random screws hoping things will work out. By the end of this course you will have a fundamental understanding of the various circuits and their functions as well as initial setup, tuning and proper rebuilding procedures. Other popular Holley models, such as the 2300, 4165, 4175 and 4500 variants will be discussed as well. This course is intended to clear up general misconceptions about carbureted fuel systems as well as give students a first hand experience on tearing down, inspecting and re-assembling a model 4150 or model 4160 carburetor. Course registration is on a first-come, first-serve basis, so take advantage by registering early! Students will be subjected to catered lunches as well as in-depth presentations/discussions by Holley's two training instructors. Each participant will be granted the opportunity to tour our manufacturing facility (which has been producing carburetors for over 60 years) and allowed a loaner carburetor for practical training and disassembly. Participants may bring their own carburetor but it must be clean, dry and free of fuel/solvent fumes. This course runs for two days and takes place at the National Corvette Museum from 8:00 AM to 5:00 PM each day. They are limited to 15 people and costs $425.00. Class registration fees are non-refundable. Class dates may be rescheduled at our discretion (subject to a rescheduling fee) no less than 30 days before your original scheduled class date. Dates Available: June 10-11 Sold Out June 12-13 10 seats available May have to schedule for next year .......
That'd be a great opportunity. My knowledge is pretty much limited to plopping another carb on when things don't work right. Happily, that's always worked, but I would like to know more about what's going on inside.
I was unaware that Holley still had the school. Holley offered a school at least in the 1950's. Their competitor, Carter, started their school in the 1930's. For those who like Holley carbs, this would be a wonderful oppertunity. Jon
I already know the basics.. jetting, power valve and using a vacuum gauge to dial in the highest vacuum reading, etc, etc... I'd like to learn about tuning with air bleeds..
I would suggest David Vizard's book "How to Supertune and Modify Holley Carburetors". Well worth the money. I am in the process of learning the internal intricacies of the Holley carb. I come from circle track racing where all I cared about was that it idled through the pits and ran well WFO. I bought and studied the Vizard book and bought an AFR gauge, along with a range of jets, power valves. air bleeds, idle feed restrictors, power valve channel restrictors, and squirters. I have been playing with the carb for about a year, making small changes and then driving it for a while. I now have it the best it has ever been. 14.5-15:1 at cruise, 14:1 at idle, and 12.6 at WFO. Haven't checked the mpg's yet, but should be an improvement. (The carb is in a '26 T coupe. Not the most aerodynamic, mpg producing vehicle.) I guess one of the biggest things I have found is, an AFR gauge will definitely up your carb game.
You get to see the Corvette Museum, the Holley Factory, and you get to ask questions when you don't understand something............THEN, you become the local "go to" guy when you get back home.......
This may help provide you with some insight. Some months ago I scanned and poster several pages from a copy of an old Ford-Autolite "High Performance Engine" catalog that I stumbled onto at a swap meet a few years ago. Lots of solid information on carbs, fuel pumps and intake manifolds. https://www.jalopyjournal.com/forum/threads/fuel-system-refresher-course.1271372/ But in my post here . . . https://www.jalopyjournal.com/forum/threads/fuel-system-refresher-course.1271372/#post-14574689 . . . I inquired about an area shown in one illustration as a "Killer Bleed" but didn't find any info that described its function or purpose. And so far no real mention of it elsewhere online. Don't even think it exists on all Holley vacuum secondary carbs. Hoping someone here with some "Ford spec'd Holley" knowledge might be able to clear up this annoying mystery. Thanks in advance for any clarification you can provide.
Holley has numerous videos on Youtube that are specific to various parts of their carbs. So a search there for air bleeds will take you to videos where they cover both idle air bleeds, and high speed air bleeds, and explain how each affects the mixture, or how they can affect both plug color, or performance. A lot of guys who sell their tuning services are ignorant when it comes to air bleeds, and even on high end carbs with threaded bleeds jets they don't know which way to go to clean up idle, or improve high end response. I had a friend take his OT Camaro with 383 stroker motor into a dyno shop and pay them $300 to "properly" tune it. When he headed home it was worse than when he took it in. I looked at the idle adjustment screws and all were either nearly closed, or barely open. The problem was his idle air bleeds were too small, and I pulled all four on the 4 corner carb, and dilled them out .004" at each. It got much better immediately, and by the time it got perfect I'd opened them up a total of .008" in the end. But it runs great, and no more stinky idle. Plus the adjustment is now about 1 full turn at each corner.
If you like watching videos, this guy on youtube has a whole series on Holley carbs. He provides a lot of good info on tuning. I got a lot out of his explanations. I linked one of the videos below and from there you can look through his channel to see a video on exactly what part of the carb you are trying to tune in if that makes sense. Holley Carburetor: Power Valve Explained - YouTube
The go to Holley man is Drew at Air, Fuel, Spark. He has several videos and actually offers a on line course. He only does genuine Ford Holleys , rebuilding them, restoring them and also does the concurs restoring. Even though he only does Ford Holley’s , the learning can be used for most all common Holley four and two barrel carbs. Bones
Yeah $425 plus hotel and travel is a lot. My Vizard's book and AFR gauge were a lot cheaper with good results. I'll bet for a lot of guys here that class would be mostly review. For a complete novice it would be a lot to take in over 2 days. A 2-day class ain't gonna make you a carb guru, but it might get you started down that path.
………there’s a Corvette museum………? great information @ekimneirbo , although my location means that I will have to stick to you tube and google for now. Thanks ! …. bttt
He's got a good video on how to convert press in air bleed jets to thread in. But haven't found one he's done that gives hints on suggested sizes for idle or high speed air bleed jets. .
Yes, and just a few years ago they had a big sinkhole gobble up a bunch of stuff and had to do a bunch of renovation.........
Yes they actually built the museum, unknowingly, over a cave system! One night the whole thing collapsed into the cave, ruining many Corvettes! It’s back up and running now….with some of the damaged Corvettes on display! Cool place! Bones
If anyone takes the class, please post a description of the textbooks, charts, etc. Holley is using. They will be copyrighted, so will not be able to copy; but a description would be nice. In the 1950's, Holley had an 8 1/2 x 11 textbook of 61 pages. The Carter textbook was over 200 pages, but the Carter school was three 3-day week-ends! Jon
My dad went to the Carter Carburetor factory school in St. Louis in the 40’s. This is his parts cabinet. He always told the story of how his instructor dealt with the know it all in class. The instructor always had an assortment of small parts in his apron pocket, he would walk up to said know it all and while giving him instructions would slip a extra screw or other small part in the student’s basket. Then come back around at the opportune time and make the student tear down the carburetor again because of the extra part in the basket.
Indeed! If your current carb is press in bleeds, then getting that shoulder for the new bleed screw to stop against is difficult with a drill press. I don't have a good mill, so I took a drill bit to a friend's shop and we turned it into a step bit that fits these holes, and cuts the stop, so I can do this in my drill press when needed. For new carbs I don't buy anything but Quick Fuel that have screw in air bleeds.
I have an old Barry Grant "Gold Claw" carb which I believe was the prototype for his Demon carb line... That carb has all the bleed screws plus interchangeable venturi boosters and venturi sleeves...
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