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Old 12-16-2017, 12:19 PM
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Tom Vaught Tom Vaught is offline
Boost Engineer
Join Date: Dec 2001
Location: The United States of America
Posts: 31,213

I decided to talk a bit about Carburetor Testing based on your post #93 today, unclescratch.

I originally worked on carbs (Tri-Power Carbs) and AFB carbs for myself. I would fix (rebuild) a Tractor carb, Combine Carb, or Irrigation Pump Carb as needed to keep the system running.

The I went to the First College and they had an Automotive program for the "Farmer" Kids as well as Engineering programs for the Aviation, Electronics, and Mechanical Engineering Guys.

So I could slip in and see what the Auto Guys were doing with their stuff. The First School had a Rear Wheel Chassis Dyno. Amazing that a 325 HP Chevelle 396 engine would only make 275 HP on the Chassis Rolls. No matter how well you tuned that "Rotten Chester" Carburetor.

I stuck with the Physics, Statics/Dynamics and Math side of the deal for the most part because you could use those to explain carburetor Function and Engine Function. This was before Neal Chance decided to create the simple Superflow 110 Flow Bench. His first bench was good for about 10-12 inches of water and 110 cfm max flow.

Course the OEMs (like Ford) had Flow Benches that could go up to 5 inches of Mercury test pressure at WOT on the Carb (68" of water).

Holley carbs (WW-II) Flow Bench could do 3500 cfm at 20.4 inches of water.

But the Flow Numbers and the Physics apply. So the test data is not as important as how you run the test. Is the test VALID?
That being said, My Old Boss, Jim Clarke used to say, "One piece of good data is worth 10,000 OPINIONS".

So I went to a bunch of Colleges/Universities as I traveled around the country and the world and
basically every Professor had an agenda (along with teaching) "I want to sell the Book(s) I wrote"
So Smith would sell his book, Heywood (MIT) would sell his books, Ellenger would sell his books,
and of course even some of our members have sold books in the past.

So I had an Opportunity to work on Draw-thru Boosted Carbs as well as Naturally Aspirated Carbs (tested on Rear Wheel Dynos and "Air Box" Flow Benches, and Engine Dynos. Lots of Tests.

Then I went to Work for Ford on a Turbocharged 1979 Mustang Engine Program. The Lab I worked in was actually more like a massive Testing Building.
Many Chassis Dynos (all certified by the Government (EPA) for accuracy).

A Garage where 40 vehicles could be "pre-conditioned" prior to testing. A garage with 20+ vehicle lifts. Lots of Mechanics, Technicians, and Instrumentation people all there to support the testing and a shift of Engineers who controlled the testing and how it was done. Try to CHEAT on the Emissions/F.E. Testing and you spend 15 years in prison. There are a few Chrysler Guys who will get a chance to visit the "Grey Bar Hotel" for years based on their cheating.

But we (as Engineers) managed the Testing and signed off on the accuracy of the data and how the test was run.

Then I swapped jobs and went to work for Ford Truck Operations. Lots of Fun Projects there.
I did the first Lightning Truck prototype. I did the first Supercharged SVT Lightning Trucks.
But where I really was happy was when they asked me to fix a Emission System on a small
Ranger truck that was failing emissions in production. By then they were well into the basic
EFI calibrations and no one knew how to do carburetors (that worked with emissions systems).
The Japanese had originally calibrated the trucks for Ford and ASSUMED A LOT OF THINGS) on
how Carburetors worked with Emissions components. They made 3 critical mistakes:
THE CARB CAN FAIL DUE TO POOR SELECTION OF PARTS. Kind of like a Racer killing a lot of parts making mistakes.

So I worked on the problem with a "Honors Graduate" out of the University of Michigan and we came up with a "FIX"
before the EPA slapped us with a $10,000 fine for each vehicle that was not complying with the standards.

People used to say, "they would not really do that Tom." Well Chrysler/Fiat has paid BILLIONS in FINES for their deal.

So to cut to the chase, the issue was fixed and we moved on. They gave me a "FREE Vehicle" for that deal. What does a vehicle cost a company?
$10,000 fine times 18,369 vehicles. A lot more money.

But my best Carburetor Job at Ford was certifying some Econoline Vans with Holley carburetors (351W engines) at High Altitude.
Denver High Altitude Emissions Lab. Flew out there (after doing the initial Emission testing at Dearborn Mi), Tested the engines/vehicles on the "Emissions Rolls" (Dynos) and then did drive evaluations up in 'God's Country' in the Rocky Mountain National Park (Estes Park, Co.).

So yes, unclescratch, I have spent time at Yucca Proving Ground and stayed at The London Bridge Hotel in Lake Havasu City Arizona, like you.
Did you take the "boat up the canyon" trip while you were there?

So One Piece of Data IS worth 10,000 Opinions.
Some have lots of Opinions on how carburetors and Superchargers work.

Tom V.

Two comments about Writing Books for people. We are fortunate that we have people like Jim Hand, Cliff Ruggles, Rocky, Jim Wangers, Pete McCarthy, and others who were able to pass on very good info in their books. My boss at Holley (Mike Urich) wrote several Holley Books, A couple of Friends: Hugh Macinnis and Don Hubbard have written Turbo Books. Craig Hendrickson and Kern O wrote ("Mini" Books) each month with the HO Racing info.
They did it because they wanted to Share Information (as Craig H) has mentioned to me several times in our phone calls to each other.

"Engineers do stuff for reasons" Tom Vaught

Despite small distractions, there are those who will go Forward, Learning, Sharing Knowledge, Doing what they can to help others move forward.

Last edited by Tom Vaught; 12-16-2017 at 12:47 PM.