Pontiac - Boost Turbo, supercharged, Nitrous, EFI & other Power Adders discussed here.

          
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Old 06-07-2019, 07:29 AM
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Default Boosting Devices and Methods for Street & Strip

Over in the Street Section, Bart "B-Man" was nice enough to create a "Sticky" about Holley Carbs and Tips.

In the Boost Section, I have thought about passing on information about Boosting in general and Turbocharging as one of the types of Boosting specifically.

So I would like to have some feedback from the members on whether they would like to have a thread similar to the Holley Carb Thread where I explain the different Boosting devices, how they actually work, some of the basic math involved, where to best put the parts in a given boost system, and how to choose the sizes of the Parts: Centrifugal Compressors, Turbochargers, By-pass Valves, Wastegates, Exhaust Manifold Flow theory, Compression Ratios, Pressure Ratios, and Compressor maps.

Tom V.

So post up here if you feel the subject would have some merit on the forums.

The sticky would probably reside in the Street Section as many of the systems might be dual usage, Street and Strip.

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Old 06-07-2019, 07:33 AM
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PY BOOST SECTION KNOWLEDGE

BOOST HISTORY

There are many different types of BOOSTING DEVICES. You can use a Supercharger, use a Nitrous Oxide System, use a Turbocharger, or multiple Turbochargers

Even if you have a Boosting Device currently on your vehicle, you may want to better understand the Decision Process necessary to properly fit the boosting device to your engine. It may also help YOU make better decisions in the future vs just trust what someone is trying to sell you is actually correct for your application. Boosting Device Systems can be different devices, as mentioned above.

The Turbocharged Engine is the most popular Boosting Device on vehicles today. One manufacturer has sold over 2 MILLION Turbocharged engines in their vehicles. Turbochargers have been on Aircraft engines as early as World War I. Improvements have constantly been added for over 100 years. Some know this, others may not.

The advantages of using a Boosted Engine Configuration are many, depending on the application.

1) A Boosted Engine can be smaller in size and displacement vs a larger Naturally Aspirated Engine.

2) A Boosted Engine's Friction and Parasitic Losses do not increase even though the power increase can be doubled or tripled. Charlie66, a PY member, has made 4 times the displacement of his 4 cylinder Pontiac Engine (over 800 horsepower from his 200 cubic inch engine.)
A few people, running Pontiac Engines have made more than 4 HP per cubic inch. Marty Palbykin was making 4 HP per cid in 1996.

3) You can have multiple choices with running an engine: Naturally Aspirated, Turbocharged, Supercharged, or Turbocharged and Inter-cooled.

Boosting (Turbocharging for example) can be both a SCIENCE and an ART. This has been posted many times.

The SCIENCE part is made up of the Mathmatical Formulas, the Physical Laws, and the Level of Knowledge of the Team Members.
The ART part is based on a "Balancing Act" of Performance vs Cost, (The availability of parts that can achieve the assumed target horsepower and your goals, vs what you actually can achieve with the resources you have available.

I mention the History of Boosting but that subject has constantly changed for over 100 years. No need to go there in any real detail.
I will just say that early attempts by the OEMs was based more on $$$ and Advertising vs actual Performance Improvements. The Corvair and the Olds F-85 Turbocharged engines come to mind.

Early attempts and wins by race teams was also based on $$$ but also on Knowledge of the Race Teams.
Several Examples are: Ohio George Montgomery's Twin Turbo Ford (Tuned by Ford's Danny Jones), Bobby Unser's Turbocharged Indy 500 1968 race winning car, and the Porsche 917 Turbocharged cars that won many of the races in the 1972 and 1972. Porsche was one of the first to use Wastegates, By-pass valves, and Variable Boost Controls.
So boosting has been out there since the early 70s with race cars that dominated their race series.

One final comment, some forms of racing have used Boosting for many years: Tractor Pulling, Trans Am Racing, Professional Drag Racing, etc.
More and more "Average Guys" are joining the "Boost World" every day based on shows like Street Outlaws, etc. All of this is great news.

More Tomorrow

Tom V.

Below is a simple illustration of the basic components in the Turbocharged engine
Attached Thumbnails
Click image for larger version

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Old 06-07-2019, 07:34 AM
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In 1979, the company I worked for, offered a Turbocharged Engine for the first time to their automotive vehicle customers. The flow schematic for that vehicle did not look like the previously posted flow schematic because the Turbo System was a Draw-Thru Turbo System. The Fuel Supply System is BEFORE the Turbocharger. A Roots Supercharger System is also a "Draw-Thru" Boosting System: The Carbs are before the Supercharger and the fuel and air pass thru the Supercharger.

This is a very good way to have a simple Boosting System for a Vehicle. Not many suppliers out there for the Pontiac Engine but the parts have been offered for Pontiacs since the 1960s from companies like Mickey Thompson and Blower Drive Service and others.
The companies (Like Eaton and Whipple) have made changes to the Superchargers to make them more efficient in moving the air without as much heat being added to the intake charge. Some, just use a different Fuel, (like methanol vs gasoline), to try to lower the Air Discharge Temperatures going into the intake system. For Drag Racing and Tractor Pulling, this is acceptable.

Tom V.

ps Superchargers on line saves me a lot of typing and offers good info on the basic systems.
http://www.superchargersonline.com/i...page=page&id=7

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Old 06-07-2019, 07:36 AM
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If you do a search, you can find information on Arnie Beswick's Roots Supercharged race cars, articles on HO Racing and their Turboforce Turbocharger system on Wallace Racing's website, If you do a search on Hot Rod and Ken Crocie's Turbocharger system upgrades and his efforts with boosting the Quadrajet Carb.

A lot of the Old Marty Palbykin Twin Turbo 406 Pontiac Engine articles seem to have disappeared but he was probably the first to go really quick with a Pontiac Engine and Turbos.

Fun to read but I am not passing on the links. My computer says that a lot of the websites have virus issues that I do not want to pass along to others. More on Turbocharger Theory tomorrow

Tom V.

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Old 06-07-2019, 07:37 AM
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Taff2 Question about Marty Palbykins Twin Turbo Pontiac Engine

My reply:

Ported Casting #62 Heads, RA-V SD Forged Steel Kellogg/Moldex Crankshaft, Eagle Rods, Ross Pistons, Custom Fabricated Intake Manifold (based on a SB Chevy Runner with Custom Plenum, Originally a Haltech EFI system, later I believe a Fast System, Originally Two Ford Staged 2 BBL throttle bodies, later 1 throttle blade per throttle body.

Mechanical Belt Driven Fuel Pump, MSD 8 Ignition System, 16 160# per hour Injectors.

1967 400 two bolt Main Block (with not drilled main webs) for splayed 4 bolt mains.
Cryogentic Chilled Block, Methanol Fuel, Custom Headers, Diesel Turbos.

Tom V.

I think I have the Back-up Roller Cam for the engine on the shelf somewhere.

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Old 06-07-2019, 07:39 AM
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Taff2 Post:
When you say diesel turbos Tom, do you mean old school Garrets? What size were they? Are the roller cam specs a secret or can you divulge details? It was on methanol I take it,going by the injector sizes. Thanks. "

Tom Earhart, was the Turbo/Dyno Guy for Marty's Pontiac Engine.
He was also the Haltech EFI knowledge Expert, had his own Engine Dyno, and
had previously dynoed a lot of BB Chevys, SB Chevys, and a couple of Ford Engines.

He had a 1000 HP Pontoon Boat (BB Chevy Powered) that he played with on the large lake he lived on.
Here is some info about him:

https://www.snowmobilehalloffame.com...s/tom-earhart/

https://www.hardcoresledder.com/foru...33-post59.html

Back in 1994, 1000 HP boosted engines was common for Earheart.

On the Diesel Turbo Question, Tom Earhart MODIFIED the Turbos extensively so any Turbo Number I gave you would actually steer you wrong on the Turbos capabilities. He had access to turbos, he had the ability to modify the wheels, he had the ability to test the modifications to see if they actually worked for him with his dyno.

Tom V.

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Old 06-07-2019, 07:39 AM
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Other People who knew/KNOW what they are doing with Turbos are:

Dave Austin (formerly of Turbonetic and Vortech Engineering.
(Dave did "Boost" engineering work for both companies).

Gale Banks and his people.

Harry Hruska (formerly the owner of PTE (Precision Turbo Engineering) who now works for Turbonetics.
Turbonetics and Precision Turbo have always been really close in their ideas and methods on how to design GOOD turbos.

Bob Keller, formerly the owner of Turbonetics, who raced turbos in the 50s and 60s
(even before Gale Banks).

Brad Lewis, currect boss of Turbonetics, and a outstanding Turbo Guy.
He worked for many years, for Bob Keller, until Bob retired. Brad had experience working for Gale Banks too, early on in his career.

Corky Bell, out of Texas, and a very good Inter-cooler guy as well as a very good author on Boosting. He has written books on SUPERCHARGING and on TURBOCHARGING.
Well worth the cost of the books to get some of his knowledge he has written about in his books.

Hugh MacInnis, wrote one of the first books on Turbocharging many many years ago and the book is still selling today. Old School ways of doing things vs EFI today but good basic knowledge.

If you read all of those books and understand the formulas and "The Why" of Turbocharging you are on your way. I have personally worked with every one of the people on the list.

Tom V.

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Old 06-07-2019, 07:40 AM
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Now that I mentioned the Important People, I will pass along a group of Formulas that every Engineer or Technician who took our class: "Engine Power Boosting" received in the hand-out. The Information was put together by a Technical Specialist named Mike Briggs.

All of the Formulas posted below came from Charles Fayette Taylor in his book:
"The Internal-Combustion Engine in Theory and Practice, Vol. 1"

Taylor Vol.1 (1-2) Formula #1 w=JQ

w= work done by the system minus work done on the system
Q= is the heat added minus the heat rejected by the system
J= a "Units Constant" 778 ft.lbs/BTU in English Units.

Taylor Vol.1 (1-4) η=P/JMfQc

η= efficiency
P= power
Mf= mass of fuel supplied per unit time
Qc= heat of combustion of a unit mass of fuel

Taylor Vol.1 (1-5) P=JMafQcη

Ma= Mass of air supplied per unit time
F= is ther mass ratio or fuel to air

Taylor Vol.1 (1-6) sfc=Mf/P

sfc= specific fuel consumption 9lbs./(BHP-hr) for English units)

Taylor Vol.1 (1-7) sac=Ma/P

sac= specific air consumption is air consumed per unit work

Taylor Vol.1 (6-2) for a 4 stroke engine

ev= 2Mi/(NVdρi

ev= volumetric efficiency (also uses ηvol)
Mi= mass of fresh mixture per unit time
N= number of revolutions per unit time
Vd= total displacement volume of the engine
ρi= inlet density

Some formulas assume Volumetric Efficiency to be 100%

Most "back of the envelope" calculations (which we are posting here) should assume
80% volumetric efficiency.

The previous formulas are used to calculate airflow for a naturally aspirated engine.
But we are talking about a BOOSTED ENGINE in this topic so:

1) You want to target numbers for Horsepower and Torque at given engine rpm points.

2) There are programs out there (like the Wallace Racing calculators) to predict for a given engine what the Volumetric Air Flow Rate and Related Pressure Ratio would be.
For the Turbo stuff you would use Borg Warner's "Matchbot"

www.turbos.bwauto.com/aftermarket/matchbot.aspx

The program is not that difficult to learn how to use and gets you in the ballpark for your Engine goals vs the right Turbocharger Size.

That is all I want to post on the Theory of Boosting today.

Tom V.

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Old 06-07-2019, 07:41 AM
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It is assumed that all "Boosted Engineers" can do some of the math required with what is called a "Back of Envelope" calculation by Mr Briggs.

So the first one is Horsepower = (Torque in ft.lbs, times RPM) divided by 5252.

Some commonly used Airflow Assumptions are:

Assumed Horsepower times 0.1 = Airflow in pounds per minute (or Lb/min)

Another way of saying that is 1 Pound per Minute of AIR MASS flowing thru the engine can make between 9.5 and 10.5 Horsepower, so simply 1 Pound per Minute of air mass = 10 Engine HP.

If you have a CFM number (Cubic Feet of Airflow per Minute) you can multiply that times .069 and get Pounds per Minute that way too.

An Example: Suppose that your engine has a True 850 cfm (List #4781) carb on it.

At WOT that carb flow 850 cfm times .069 would equals 58.65 pound per minute of airflow. 58.65 Pounds per Minute times 10 is equal to 586.5 horsepower from that Holley carb. Doesn't matter if it is flow thru a carb or flow thru a Turbocharger.

If ONE Turbocharger can move 78 pounds of air-mass thru it, that Turbocharger will make 780 HP if you do things right.
Two Turbos would make 1560 horsepower.

So working with Lbs per Minute is more accurate than using CFM.

A pound of air mass never changes. The density of air per cfm DOES CHANGE with weather conditions.

Tom V.

I ran across this link on the web today (which comes from one of the Turbo books that explains air density too)
here is the link: https://books.google.com/books?id=hh...%20%3D&f=false

So maybe you do not need to buy that book to get that info.

Tom V.

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Old 06-07-2019, 07:42 AM
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Post by Taff2, Cheers Tom, I already have my turbos -was just curious what Marty had. Yes, I have Corky Bell's/Macinnis'/Allard's/AK Millers books,along with a few others. Macinnis book was what really got me interested in turbo power.

Between those books is a tremendous amount of Aftermarket Boost Knowledge.

Maybe not so much on the High Volume Production side of the subject but tons of historical knowledge.

Tom V

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Old 06-07-2019, 07:43 AM
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I have a couple of comments on the Turbocharger and Supercharger Manufacturers generate their Compressor Maps.

The Garrett, Borg Warner, IHI, Turbonetics, and Precision Turbo people typically have Compressor Maps that tell the buyer where things like the Surge Line is, what the Lbs per Minute capability of the Compressor is, Where the Compressor Efficiency Islands are located on the Compressor Map and the Temperature and Pressure conditions where the unit was tested.

Attached are three typical Compressor Maps (each showing an important point on the compressor map.

I also posted a link to a youtube video on how to read the Compressor Map.

https://www.youtube.com/watch?v=rTaUbMfWdA8

Tom V.

I am not going to repost the map images.

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Old 06-07-2019, 07:45 AM
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B-Man Post "Added to the Pontiac Street forum tech thread archives 'sticky' thread."

Sorry you had to do this twice Bart.

Tom V.

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Old 06-07-2019, 07:46 AM
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4zpeed post:

Thanks Bart, appreciate you adding the header to the thread.

Thank you as well Tom.

Tom V.

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Old 06-07-2019, 07:46 AM
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Thank You Bart, and PY, very much. Tom V.

The Compressor Maps posted in Post #18 are good as a basic way to identify where conditions change as the Turbocharger is operating.

The First Picture shows a map with the SURGE LINE identified.

The Pressure Ratio numbers are on the left side and listed in a vertical order with the higher pressure ratio numbers at the top.

If you have a Pressure Ratio number of 1 then you have 1 atmosphere of air entering the induction system.

If you have a Pressure Ratio of 2 you have about 15 psi GAGE "BOOST PRESSURE".

If you have a Pressure Ratio of 3 you have about 30 psi GAGE "BOOST PRESSURE".

Same deal for Pressure Ratios of 4 or 5 or 6.
A Pressure Ratio of 4 being about 45 psi GAGE "BOOST PRESSURE".
A Pressure Ratio of 5 being about 60 psi GAGE "BOOST PRESSURE".

Once you get over 5 Pressure Ratio you are dealing with very expensive Turbos like the ones used in Tractor Pulling or the people are using COMPOUND BOOSTING methods.
One Boosting Device pressurizing a second boosting device.

Back on the Surge Line for a minute. The Surge Line drawn on the map is not a ABSOLUTE LINE, the Surge Line can move so that on one engine the line may be a bit more to the left on the map and on a different engine the line may be a bit more to the right. The line also has a variable vertical path that can deviate from the Turbo Suppliers "Mapped" turbo on the Turbo Test Stand.

So what is SURGE? Here is a little Video where a guy is explaining "Turbo Flutter" or SURGE. https://www.youtube.com/watch?v=FwzUffAuQyc

Turbo Surge is caused by the Turbo trying to pump more Mass Flow thru the engine vs what the engine Throttling System is allowing. The Throttling System could be that the
physical engine size is the wrong size for the Turbocharger used.

Turbo Surge can also occur when the Turbo and engine are happy at a given rpm and load point and the driver suddenly closes the throttling device. Now the turbo is still trying to pump Mass Flow thru the engine but you suddenly stopped that mass flow.
THE TURBO IS NOT HAPPY WHEN IT GOES INTO SURGE. IN SOME CASES THE COMPRESSOR WHEEL TIPS MAY TOUCH THE COMPRESSOR HOUSING. This is very hard on the Turbo "Shaft Bearing System" and the thrust bearing in the Turbocharger CHRA.

CHRA is the Compressor Housing Rotating Assembly. It is made up of the Shaft, the Compressor Wheel, the Turbine Wheel, The Support Housing/Oil housing for the Turbo Bearing Assy, and and on some turbos the Water Cooling System for the Turbo.

So a Turbocharger is a complicated device. The Turbocharger CHRA is also balanced to allow over 100,000 rpm shaft & wheel speeds.

So when the Turbocharger is in SURGE, things are not happy and the Turbo typically makes a unique noise.

One way to eliminate SURGE when the Throttle Blade(s) is closed is to use a Compressor By-Pass Valve. You close the Throttle quickly and vacuum (negative pressure) is restored in the intake manifold. You can use that Vacuum to open the CBV and eliminate some of the Surge. In some cases it may take more than one CBV to quickly remove the potential for Turbo Surge.

Centrifugal Superchargers also use Compressor By-Pass Valves to reduce/eliminate Surge. They are plumbed basically the same way that a Turbo Set-up would be plumbed.

The one application where you would not typically need a Compressor By-pass Valve would be when using a Draw-Thru system.

A Draw Thru system has the Throttling Device in front of the Boosting Device.

A Holley Carb/ Roots Supercharger would be a Draw Thru System, No By-pass Valve Required.

The Pontiac 301 Turbo System was a Draw Thru system that used a Rochester Q-Jet Carb in front of the Turbocharger. No By-pass system required. A picture of the 301 components is shown below.

More on Surge Later

Tom V.

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Old 06-07-2019, 07:47 AM
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Next I would like to explain what the Efficiency Islands mean.
So first I will post the Efficiency Island Image again and then go thru the text a step at a time with updates to this post. TV

A) On the Compressor Map shown you have the Pressure Ratio (vertically) on the left side of the graph.
You have the Mass Flow in Kilograms per Second across the bottom of the graph (map).
You have the Efficiency Islands plotted in the center of the (map).
The Efficiency Islands go from a high of 78% to a low of 66% on the (map).
The Surge Line is on the Left of the (map) and the Choke Line is on the right side of the (map).

So what does all of this mean?

You would like for the Compressor Flow to follow a specified path that keeps it away from the Surge Line, it travels upward on a angle to the Pressure Ratio you want the Wastegate to control at, and then it moves horizontally to the right to the Mass Flow Target (in Kilograms per Second) that you are targeting (without crossing into the Choke Zone.

So in an ideal world the Compressor Map line would go from the 1.4 pressure ratio and .08 kilograms/sec point to the 2.8 pressure ratio and .28 kilograms/sec point and then the Wastegate(s) would control the pressure Ratio at 2.8 pressure ratio across the map to the 2.8 pressure ratio and .48 kilograms/sec point. The mass flow point (.48 kilograms per second) is the same thing as having 63.5 lbs/minute of air mass flow going thru the engine. That means that if the Turbo Compressor followed that Pressure Ratio profile it would make 630.5 horsepower from that turbo at 2.8 pressure ratio.

2 pressure ratio is about 15 psi of Boost Pressure, 3 pressure ratio is about 30 psi of boost pressure so with less than 30 psi of boost pressure you could make 1260 horsepower with two of these smaller turbochargers shown on the compressor map. Now Charlie66 has made over 800 HP from One Turbocharger on his 4 cylinder Pontiac engine.

So obviously Charlie66's Turbo Map is a bit different from the one in the example but the theory remains the same.

Tom V.

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Old 06-07-2019, 07:49 AM
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The Next Post will expain the Different Regions of a Compressor Map which I used as an example in the previous post. Again I will attach the image and then add info to the post. The Speed Lines as well as the rest of the points on the map can be identified in several different ways. (From the Borg Warner website)

"Speed lines are the last additional bit of information contained within the compressor map. The speed lines run from left to right across the efficiency islands and represent a specific speed of the compressor. These speed lines are typically measured and identified in meters per second, feet per minute, or rotational speed."

Rather than type all of this info over again I will just post the link to the Engine Labs/ Borg Warner website that basically says everything that I have posted above. https://www.enginelabs.com/engine-te...-turbocharger/

Tom V.

Do a search on Compressor maps and you can look at images of the maps and figure out the words I posted last time

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Old 06-07-2019, 07:49 AM
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All of this info is out there on the web, I will just try and explain in everyday terms what the info says in the articles or links.

Sometimes the Units used can be confusing: Meters per second, Kilograms per second, Pressure ratios, but I will try to explain each as best as I can. I will also try to expain what the different components actually do. CHRA being one example.

Tom V.

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Old 06-07-2019, 07:50 AM
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A bit more of a technical explaination for SURGE.

A surge is a "Blade" phenomena. It can happen on Blade Style Compressors.
(These would typically be in the automotive world, Turbochargers, Vortech/Paxton Superchargers, or Procharger Superchargers. Turbo Manufacturers and Vortech/Paxton Superchargers create maps for their units to show where the Surge/Stall phenomena would occur at. Procharger does not generate Compressor maps unless they started in the last couple of years.

A occurrence, of stall on one or two blades may happen to any centrifugal style supercharger. This has to do with Air Blade Filling and can be caused by plumbing issues on the inlet side of the Compressor Cover.

When ALL of the Blades Stall, the flow through the compressor becomes choked you get no overall flow, and at times the flow reverses direction. This is very bad for an Boosting device and can be bad for the engine, as the engine would be starved of oxygen causing a serious loss of power. The choking of the engine can be very unstable - the flow can restart, and re-choke continuously, creating very violent vibrations to the drive system and the engine. With belt driven superchargers many times the belt comes off the supercharger pulley. Pontiac Dude used to have that issue a lot. Some blamed it on his bracket design and some thought it was because he was pedaling the engine. It could have been from the wrong Boosting Device on the engine too.

Usually when the bearings are sloppy in a Turbocharger the engine has usually seen SURGE or even CHOKE.

The Boosting Manufacturers TRY to help you install the correct boosting device for your present application. Sometimes when you move to a new combination the same device will still work ok. Other times the boosting device goes bad and then the buyer wants his unit replaced and the fault was with the owner, not the manufacturer.

Enough about Surge/Stall for the time being.

Tom V.

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  #19  
Old 06-07-2019, 07:50 AM
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Tom Vaught Tom Vaught is offline
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Just for fun using Excel we put in Marty Palbykin's " assumed" Torque and Horsepower numbers and see what we get for a horsepower number.

I don't quite remember the RPM of the engine or the Torque number from Earhart's dyno
but we are just playing a few games with numbers anyway.

So if we assume that:

Marty's Max Torque number was 1250 at 6700 rpm.

Hp = (1250 torque times 6700 rpm) divided by 5252 = 1594.63062 HORSEPOWER

(and we assume that 1 lb of air mass will make 10 hp) we get

159.463 lbs of air mass required to make that HP number

We multiple that 159.463 lbs of air mass times 1/.069 and we get 2311.059 cfm needed

2311.059 cfm times 28.32 and we get 65449.19 liters per minute

So now we do some math on the engine size: =(1/2) (6.6L)(6700)(.8)
= 17688 liters/min

65449.19 liters/min divided by 17688 liters/min = 3.70020 Pressure Ratio

3.70020 Pressure Ratio = 39.692 psi of boost pressure in the intake manifold.

So all of the assumed numbers kind of line up with published figures in some of the magazines and what we know from the actual testing of the vehicle.

So now you have a math process that would allow running the same equation on the Raven engine or wreckmasters engine.

Tom V.

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  #20  
Old 06-07-2019, 07:51 AM
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Tom Vaught Tom Vaught is offline
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There are basically TWO types of "Superchargers"

One type is mechanically driven by the engine (It might be driven by a Belt, or by a "Drive Mechanism" off the front of the engine. This type is commonly called a "SUPERCHARGER"

The other type is driven by the ENERGY of the engine's exhaust gases. This type is commonly called a "TURBOCHARGER".

In some Reports/Publications/Books, the Turbocharger is called a "Turbo-Supercharger".

EACH TYPE OF SUPERCHARGER OR TURBOCHARGER HAS ITS OWN BENEFITS AND DETRIMENTS.

Superchargers have several benefits over Turbochargers:

1) The supercharger is not incorporated with the engines exhaust system so the boosting devices have lower internal operating temperatures.

2) Many Superchargers (like Roots Superchargers and Procharger Superchargers have self-contained" lubrication. This means that a engine or supercharger bearing failure does not pass oil (with failed material) to the Supercharger or vise-versa.

3) Some Superchargers (like the Paxton and Vortech superchargers) do use engine oil for cooling of the bearings but they also in some cases have an extra small oil filter cleaning the oil before it reaches the supercharger. Rarely does the Paxton or Vortech supercharger ever fail and pass material to the engine oil pan thru their drain system.

A disadvantage of the Belt Driven or gear driven devices is that the Supercharger drive parasitic losses are now added to the engines drive losses. In some cases that can be over 100 additional hp at max boost pressures. So your boosted 1400 HP engine does not transmit that 1400 HP to the drivetrain, it only transfers 1300 HP to the drivetrain.

Any device that has the potential to add additional air to the Engine is a form of supercharging device. Be it a normal belt or gear driven device or a NOS system.

The THREE MOST COMMON "mechanically driven" Superchargers are the 1) Roots devices, 2) The Lysholm Screw devices, and 3) the Centrifugal devices: Paxton, Vortech, and Torkstorm units.

Lesser known Superchargers are the Comprex-Pressure Wave Supercharger, the Latham Axial Flow Supercharger, and the "Vane Blade" Supercharger (whose design was used for several years in Emissions Air Pumps.

Info on Turbochargers later.

Tom V.

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