Copyright: EPI Inc.       Contact: tech@epi-eng.com
Last Significant Update: 05 June 2024

- Revision History -

A chronlogical list of updates and changes to this site

NOTE: All our Products, Designs. and Services are SUSTAINABLE, ORGANIC, GLUTEN-FREE, CONTAIN NO GMO's, and will not upset anyone's precious FEELINGS or delicate SENSIBILITIES.

05 June 2024

  1. In an effort to get this site converted from HTTP to secure HTTPS, we contacted several self-proclaimed "web desigh experts" over a period of years. Those contacts always resulted in a conversation with a "technical person" person who barely spoke English, and with whom we could not establish a comprehensible plan.
    Recently, however, we were gifted with the aid of a true expert, who guided us through the process of converting to HTTPS. - - - SO, now the entire website is "secure", and visitors no longer have to worry about GOOGLE telling then "this site is not secure". It most certainly is now. Sincere thanks to Mr. Allgaier.

03 January 2024

  1. Added a new page describing a detailed methodology for the design and analysis of a PSRU.

04 December 2023

  1. Added a significant amount of new information and videos about the EPI Mark-15 PSRU ;
  2. Added a new video showing the first test flight of the EPI Mark-25 Helicopter Transmission System ;
  3. Added some new information to the Combustion Analysis page.
  4. Updated the Valvetrain Technology-Part 1 page;
  5. Added Valvetrain Technology-Part 2.
  6. Added a major update to the page on Climate Change / Global Warming Lunacy.

04 August 2023

  1. Added a new page describing a PSRU designed specifically for high-output VW-based engines.

03 July 2023

  1. An update and expansion of the page detailing the Building a "Reverse Rotation" V8 Engine, that also addresses the later LS-style engines with the oil pump on the crankshaft.
  2. An update to the HyVo Chain Issues page, expanding on the technical content.
  3. An update to the Properties of Belt Drives page, pointing out some of the potential problems with a fixed-center toother belt drive.
  4. An update to the Evaluating a Conversion page, adding text to clarify some of the statements made there and some slight revisions to the weight comparison table at the bottom of that page.
  5. A revision to the Engine Conversions on Certified Aircraft page, providing some recent (2023) information on reportedly-successful conversions.

24 December 2021

  1. A MAJOR piece of performance testing data regarding our New O-200 Replacement Engine

08 December 2021

  1. This update consists of a brand new page detailing the analysis of the forces imposed on the reciprocating components in a piston engine, incuding explanations of primary and secondary vibration forces in various engine configurations.
  2. Minor updates to several other pages.

16 February 2021

  1. This update consists of a brand new page detailing the design, construction and development of an innovative rear-engine, hemi-powered midget race car..
  2. Minor updates to several other pages.

10 January 2021

  1. This update consists of a major expansion of the page describing Engine Lubrication Systems.
  2. Minor additions to several other pages.

03 June 2020

This update consists of two major revisions, and minor additions to several other pages

  1. A notification to potential clients that EPI, Inc. no longer has any involvement in the Clean Sheet V-12 Engine Project;
  2. An important update to include the LT-5 engine in the recently-added information in the recently-updated page describing the GM LS { and now LT } engines and their suitability for aircraft use;

22 May 2020

This update consists of two major revisions, and minor additions to several other pages

  1. A long-overdue update to the page describing the GM LS (and now LT) engines and their suitability for aircraft use;
  2. An update to the Crankshaft Design page that adds some clarity to the concept of crankpin overlap, with new illustrations and comparison numbers

06 May 2020

  1. This update consists of a major expansion of the page describing the improvements we made to a large (3600 HP) 2-stroke Diesel Engine, and some minor additions to several other pages.

18 January 2020

This update contains several major additions and revisions:

  1. A new page describing the complete turbine helicopter power transmission system that EPI designed for a new European helicopter;;
  2. A new series of 12 pages describing the detailed design approach taken on our Clean-Sheet 1800-hp V-12 engine, which could be seen as a presentation of Engine Design-101;
  3. An UPDATE on the new O-200 Replacement engine;
  4. A new page in the Engine Technology section discussing Piston Engine Detonation and Pre-ignition;
  5. A new page in the Engine Technology section discussing the Technology of Combustion Analysis;
  6. A new page in the Engine Technology section discussing HOW NOT TO BUILD AN ENGINE;
  7. A significant revision to the Propeller Performance page;
  8. Updates on the Mark-15 Propeller Reduction Gearbox;
  9. Updates to our EPI Specialties page;
  10. A new page addressing the absurdity of contemporary energy mythology..

22 April 2019

  1. This update consists of some added information on our new O-200 Replacement Engine and updates on the progress of the project.

31 Dec 2018

  1. This update consists of a major addition to our page that introduces torsional vibration issues in propeller reduction gearboxes powered by piston engines. Some amazingly deceptive claims about this subject have arisen of late, and they pose a danger to purchasers of the hyped systems. This addition presents and refutes the worst of those claims.

14 Aug 2018

  1. In the twelve months between this update and the last one, there have been numerous small updates to various pages to clarify and / or add to certain descriptions. This update includes a substantial revision to our SITE MAP .

17 Aug 2017

  1. A NEW PAGE has been added, describing the design and development of a clean-sheet, 4-cylinder air-cooled aircraft engine.
  2. In the ten months between this update and the last one, there have been numerous small updates to various pages to clarify and / or add to certain descriptions. This update includes a substantial revision to our HOME PAGE

21 Nov 2016

  1. Added two new videos to the EPI V-12 Engine page.
  2. Minor updates to several other pages.

17 Sep 2016

  1. Added a new page to describe the complete, mobile engine dynamometer system that EPI designed and built for the development of a new 200 HP turboshaft engine.
  2. Minor updates to several other pages.

02 Jul 2016

  1. Added a new page to clarify the often-misused terms "tolerance" and "clearance".
  2. Minor updates to several other pages.

11 Mar 2016

  1. Updated the information and progress for the new EPI V-12 Engine.
  2. Updated the EPI Products and Services page.

27 Mar 2015

  1. Added a page describing the features of the new EPI V-12 Engine.
  2. Updated the EPI Products and Services page.

12 Jan 2015

  1. Updated the Engine Technology Section pages diescussing BMEP and the Comparison between F1 and CUP Engines.

02 Oct 2014

  1. Updated the page on the GP-5 Reno Racer with the tragic news of the loss of this aircraft and its pilot / owner at the 2014 Reno Air Races.

08 Aug 2014

  1. Updated the page on the GP-5 Reno Racer with news about new speed and climb records set by Lee Behel in that airplane.
  2. Updated the Race Engine Technology SPECIAL REPORTS page to describe the content of the new, information-packed FORMULA ONE Race Technology (Volume 7) .
  3. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current TENTH ANNIVERSARY ISSUE of Race Engine Technology Magazine, Issue 71;
  4. Added the description of Issue 70 of Race Engine Technology Magazine (which we failed to report in a timely manner) to the Race Engine Technology BACK ISSUES page.
  5. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

01 Aug 2013

  1. Updated the page on the GP-5 Reno Racer with news about recent PSRU improvements and pictures from Oshkosh-2013;
  2. Updated the Race Engine Technology SPECIAL REPORTS page to describe the content of the new, information-packed FORMULA ONE Race Technology (Volume 7) .
  3. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current TENTH ANNIVERSARY ISSUE of Race Engine Technology Magazine, Issue 71;
  4. Added the description of Issue 70 of Race Engine Technology Magazine (which we failed to report in a timely manner) to the Race Engine Technology BACK ISSUES page.
  5. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

11 Apr 2013

  1. ANNOUNCING A MAJOR, 40% DISCOUNT, ONE-WEEK SALE from April 10 to April 17, 2013 ON RACE ENGINE TECHNOLOGY BACK ISSUES, and SPECIAL REPORTS.
  2. Updated the Race Engine Technology SPECIAL REPORTS page to describe the content of the new, information-packed NASCAR CUP Race Technology, Volume 4 issue.
  3. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (069).
  4. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

13 Mar 2013

  1. Added a New Page describing a dyno gearbox we designed and built for a major race engine company.
  2. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (068).
  3. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

26 Jan 2013

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue.
  2. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

09 Oct 2012

  1. Added a new page packed with information on the George Pereira-designed GP-5 Reno Racer ("Sweet Dreams") and the 2012 Reno Air Races.
  2. Updated the Mark-9 PSRU page, detailing new developments with that gearbox..
  3. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue.
  4. Updated the Race Engine Technology SPECIAL REPORTS page to describe the content of the new, information-packed 24 HOUR Race Technology 2012, Volume 6 issue.
  5. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

01 Aug 2012

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (062).
  2. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

30 Jun 2012

  1. MAJOR CHANGE: The Hosting Company with which this site has resided since its inception has recently allowed files in our site to be corrupted with malware (Blackhole and other threats). Our site was flagged by Google as potentially malicious. We repeatedly requested the hosting company to fix their security vulnerability, but after several days of work and no apparent solution to the problem, today we switched to AptHost. Reports from Knowledgeable Web People suggest this hosting company is very secure and very attentive to making sure that malware does NOT infect the sites they host.

05 Jun 2012

  1. Updated the 620 HP Cropduster Engine page to present current news with this project.
  2. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue.
  3. Updated the Race Engine Technology SPECIAL REPORTS page to describe the content of the new, information-packed FORMULA ONE Race Technology 2012, Volume 6 issue.
  4. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

21 May 2012

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue.
  2. Updated the Race Engine Technology SPECIAL REPORTS page to describe the content of the new, information-packed NASCAR CUP Race Technology, Volume 3 issue.
  3. Updated the Race Engine Technology SPECIAL REPORTS page with larger, higher-resolution pictures for all the Special Reports issues.
  4. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

20 Mar 2012

  1. Updated our PSRU Overview Page.
  2. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (059).
  3. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

02 Jan 2012

  1. Updated our Home Page.
  2. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (058).
  3. Updated the Race Engine Technology SPECIAL REPORTS page to describe the content of the new, information-packed Drag Race Technology, Volume 2 issue
  4. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

11/01/11

  1. Updated our Home Page.
  2. Updated the current status and technical information on the Mark-15 propeller reduction gearbox.
  3. Updated the information on the STC'd standby alternator drive system for the Texas Turbines engine conversion for the Cessna Caravan.
  4. Updated the page describing our T-62 Turbine Engine-based oil exploration powerplant
  5. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (056).
  6. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

09/01/11

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (055).
  2. Updated the Race Engine Technology SPECIAL REPORTS page to describe the spectacular content of the latest 24 Hour Race Technology issue (Volume 5).
  3. Corrected a GRAVE ERROR in the Race Engine Technology SPECIAL REPORTS section, in which the 24-Hour Race Technology Volume 3 and Volume 4 content descriptions were merely copies of the Volume 2 content. (We REALLY don't know how that happened, and worse, why it took so long to notice ; SORRY.)
  4. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

06/28/11

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (054).
  2. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

05/16/11

  1. Updated the Race Engine Technology SPECIAL REPORTS page to describe the content of the new, information-packed Formula One Racing Technology issue
  2. Updated the discount subscription offer to Race Engine Technology Magazine and the Special Reports.

05/05/11

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (053).
  2. Updated the discount subscription offer to Race Engine Technology Magazine.

03/11/11

  1. Updated and clarified several pages in the Engine Technology and Mechanical Basics sections
  2. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (052).
  3. Updated the discount subscription offer to Race Engine Technology Magazine.

01/14/11

  1. Updated the Race Engine Technology SPECIAL REPORTS page to describe the content of the new, exciting CUP Racing Technology issue
  2. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (051).
  3. Updated the discount subscription offer to Race Engine Technology Magazine.

11/26/10

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the landmark 50th issue of this amazing journal
  2. Updated the discount subscription offer to Race Engine Technology Magazine.
  3. Added a new page to the Special Purpose Systems section describing a new system EPI built for a major NASCAR engine developer.

11/15/10

  1. Updated the Race Engine Technology CURRENT ISSUE page to restore the discount subscription offer.
  2. Added an entire new section (Special Purpose Systems) which describes some of the customer-specific systems and solutions EPI has designed and implemented (NASCAR, 2-Stroke Diesel, TPE-331 conversion, and more).

10/16/10

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (049), available 10/13/10.
  2. Updated the technology page which disusses the Basics of Gear Design
  3. Updated the EPI Mark-15 PSRU page with new developments and configurations.
  4. Corrected a minor arithmetic error in the Thermal Efficiency page of the Engine Technology section.

09/30/10

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (048), available 08/17/10.
  2. Slight revisions to wording and descriptions on our Home Page

08/05/10

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (047), available 07/05/10.
  2. Removed the page discussing the ambiguities and contradictions in the published 2009 Engine Masters Challenge rules and the responses from the organizers attempting to resolve those problems.

06/01/10

  1. Expanded the discussion of Power and Torque to include an explanation of the power consumed by fluid pumps.
  2. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (046), available 06/01/10, and to extend the discount subscription offer.
  3. Updated the Race Technology SPECIAL REPORTS page to include the newly-released and jam-packed with information F1 Race Technology, Volume 4.

04/23/10

  1. Expanded the discussion of BMEP to include the derivation of the equations used to calculate BMEP for both 2-stroke and 4-stroke engines.
  2. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (045), available 04/16/10, and to extend the discount subscription offer.

03/12/10

  1. On March 5, 2010, the NTSB published the full report of the tragic accident which took the life of a good friend, Dr. Doug Pohl, when the V8-powered LancAir-4P he owned and operated lost power on takeoff. The V8 engine used the EPI Mark-9 PSRU, which was torn off the engine in the nose-down crash. Although the PSRU was intact, the shaft which couples the engine to the PSRU was broken during that impact. The NTSB's metallurgical inspection and analysis of that input shaft confirmed that it broke during the impact and was not a factor in the accident, as some critics had claimed.

    The full history of the Mark 9 was updated, and the NTSB report on the accident was reproduced and included in this update.

03/08/10

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (044), available 03/06/10, and to extend the discount subscription offer.

12/21/09

  1. Added a new page discussing the use of Electronic Engine Controls in aircraft applications.
  2. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (042), available 12/03/09, and to extend the discount subscription offer.

10/26/09

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (041), available 09/03/09, and to extend the discount subscription offer.
  2. Added to the Race Engine Technology CURRENT ISSUE page, a list of articles by EPI that have appeared in Race Engine Technology, with links to those articles.
  3. Added cover pictures and content blocks for Issues 001 through 015 to the Race Engine Technology BACK ISSUES page.

09/22/09

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (040), available 09/03/09, and to extend the discount subscription offer.

07/15/09

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (039), available 07/09/09, and to extend the discount subscription offer.

06/20/09

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (038), available 06/07/09, and to extend the discount subscription offer.
  2. Added a summary of the new (Volume 3) Formula One Technology Special Report.

04/29/09

  1. Added a new page to the Engine Technology section describing the science and implementation of 4-Stroke Piston Engine Exhaust Systems.
  2. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (037), available 04/15/09, and to extend the discount subscription offer.

03/17/09

  1. Updated the Mark-15 PSRU Gearbox page to show current status and pictures of the new gearbox main housing castings
  2. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (036), available 03/06/09, and to extend the discount subscription offer.
  3. Added the essence of the Engine Masters Rules Committee Responses to our more than 30 questions about contradictions, ambiguities and just plain incoherence in the 2009 rules document.

02/05/09

01/31/09

  • Added a NEW PAGE which discusses the pervasive vagueness, ambiguity and contradiction present in the Engine Masters Challenge 2009 Rules Document, the refusal of the EMC bureaucrats to address specific requests for clarification, and the politician-worthy sidestepping and convenient rule-changing, which has turned this previously-prestigious competition into a farce.

01/12/09

01/01/09

  1. Added a new page on Crankshaft Design.
  2. Added a new page on Advanced Engine Materials.
  3. Added a new page on Turbocharger Technology.
  4. Removed the page dedicated to Piston Velocity and Acceleration and integrated it into the Piston Motion page, with improved graphics and more explanations.
  5. Added lots of new material to the Crankshaft Torsional Absorber page.

11/20/08

  1. Updated the Race Engine Technology CURRENT ISSUE page to describe the content of the current RET Issue (034), available 11/15/08, and to extend the discount subscription offer.
  2. Added information to the LS-Engine Page regarding concerns about ECU-based aircraft powerplants.

10/18/08

09/04/08

  1. Updated the Race Engine Technology Current Issue page to describe the content of the current RET Issue (032), available 08/27/08, and to extend the discount subscription offer.
  2. Added content descriptions of back issues 016 thru 019 to the Race Engine Technology PAST ISSUES Page.

08/24/08

07/09/08

  1. Updated the Race Engine Technology Current Issue page to describe the content of the current RET Issue (031), available 07/05/08, and to extend the discount subscription offer.
  2. Added several new entries to the Engines and Turbomachinery section of the Reference Library.
  3. Added 3500 watt Honda Generator to Stuff For Sale.

06/12/08

05/29/08

  1. Expanded the description of the Engineering Services available from EPI, Inc.
  2. Updated the Race Engine Technology (RET) Magazine page to describe the content of the current RET Issue (030) and to extend the discount subscription offer.

05/15/08

  1. Added the comparison of NASCAR CUP V8 engines vs. F1 V8 engines to the engine technology section.
  2. Added new pages describing the content details of Race Engine Technology Past Issues from issue 020 to issue 029, and the Race Engine Technology Special Reports on CUP, 24-Hour and F1 race technology.
  3. Added new information to PSRU Technology pages: Introduction, Implementations, PSRU Torsional Vibration.
  4. Added new information about Aircraft Engine Conversions to the Evaluating a Conversion page.

03/31/08

  1. COMPLETE REMAKE OF THE WEBSITE; NEW FORMAT, NEW PRESENTATION, NEW LOOK.
  2. Broke PSRU Products and PSRU Technology into separate sections, and expanded the PRSU Products section to include our other transmissions with the Propeller Reduction Units.
  3. Broke Engine Technology and Aircraft Engine Products into separate sections.
  4. Updated several of the Mechanical Basics and Engine Technology pages.

03/18/08

  • Added DISCOUNT SUBSCRIPTION OFFER for the World's Premier Engine Technology Magazine:
    RACE ENGINE TECHNOLOGY.

01/14/08

  1. Updated the Mark-15 Gearbox pages to show the improved housing design and the fact that the governor drive subsystem has been revised in order to move the governor mounting-face nearly an inch inboard in order to eliminate potential cowling interferences with replica fighter aircraft such as the PAPA-51 Mustang and the FEW Mustang. 
  2. Updated the 3-view drawings and 3D downloadable model to reflect the changes described above.

01/08/08

  1. Expanded the discussion of planetary reduction units in PSRU Section..
  2. Cosmetic changes and link updates.

11/06/07

  1. Removed the bargain RotorWay Helicopter for sale.
  2. Expanded the treatment of the Hy-Vo Chain PSRU section to better address some of the misleading claims made about those units.
  3. Expanded the description of Propeller Strike Damage to include information from AD-2004-10-14.

09/23/07

08/21/07

08/20/07

  1. Reorganized and expanded the section on RotorWay Secondary Failures.
  2. Added a page describing, in detail, the operation of the RotorWay Autorotation Clutch.
  3. Added a page describing current problems with the EPI Secondary Upgrade.
  4. Removed the pages describing the EPI Secondary Upgrade product.
  5. Removed the pages describing the EPI Turbine Conversion for the RotorWay Helicopter.

06/12/07

  1. Published updated Installation Drawings of the Mark 15 gearbox product.
  2. Published updated information on the EPI Gen-2 V8 engine.

03/28/07

03/07/07

  • Updated the STUFF FOR SALE section to show all items have been sold.

02/26/07

02/08/07

  • Posted BRAND NEW 505-HP GM  LS-7 ENGINE FOR SALE.

02/03/07

01/28/07

  • Since the last "official" update (08/29/06) there have been several small updates to improve and clarify various presentations here. This revision reorganizes and updates the ENGINES & TECHNOLOGY section of the site. Further updates to that section, scheduled for later this year, will include the material which EPI's CEO presented at the 2006 Advanced Engine Technology Conference (AETC)

08/29/06

07/27/06

07/07/06

  • Updated RotorWay Turbine Conversion Information.

06/15/06

  1. Added FEA results for critical Mark-15 Propeller Reduction Gearbox components.
  2. Updated Piston Velocity & Acceleration page in the Engine Technology section.

05/24/06

05/02/06

  1. Lowered website price of RotorWay Billet Rocker Covers.
  2. Added progress information on RotorWay Turbine Conversion ("Mark-17").
  3. Added new information on the Mark-15 Propeller Reduction Gearbox.

04/17/06

03/24/06

03/18/06

03/09/06

  1. Added new information, pictures and dimensions of the Mark-15 Propeller Gearbox; Added new information on EPI LS-based and Big-Block-based engines.

01/30/06

01/14/06

  • Added five new pages with new information on the Turbine Conversion for the RotorWay Helicopter, including pictures and more details on the Power Unit, Main Rotor Drive, Tailrotor Drive, Fuel System and Control System.

01/04/06

  1. Reorganized the ROTORWAY HELICOPTER PRODUCTS section, with new information.
  2. Added new information on the Turbine Conversion for the RotorWay Helicopter.
  3. Added new information in the Aircraft Engine Conversion section, explaining how to decide whether a proposed engine swap is rally a good idea.

12/15/05

  1. Complete revision of the Aircraft Engine Conversion section with a new page describing the new "21st Century Cropduster".
  2. New information on the redesigned EPI Mark-15 Propeller Reduction Gearbox.
  3. New section on Propeller Performance and how to make a good selection of a propeller for your aircraft.
  4. New section explaining the effects of Torsional Excitation on a propeller reduction gearbox.

12/12/05

  • Revised Rotorway Secondary Upgrade pages for clarity, brevity, and price decreases.

09/14/05

  • Announced the NEW, Finned Billet-Aluminum Rocker Covers for the Rotorway Engine.

08/23/05

  • Reorganized and clarified the entire RotorWay Secondary Drive section; added information on the EPI Secondary System Test Flight Program; Expanded several technical discussions in the EPI Secondary Upgrade section. 

07/09/05

  1. Updated several technical discussions in the EPI Secondary Upgrade section of the RotorWay Secondary Drive section.
  2. Updated RotorWay Secondary Known Failure Database

12/27/04

10/25/04

  1. Added a SEARCH capability to enable visitors to find information more easily.
  2. Added 4 new pages and updated several other pages in the RotorWay Secondary Drive section to include the data shown in EPI's technical presentation at Homer's-2004, including a detailed explanation of the Higher Shaft Load from the ProDrive Belt System, a Comparison of the EPI and ProDrive Secondary Shaft, and a page covering seven important Gates Belt Issues.
  3. Added lots of new details, options, and pricing information on the EPI Secondary Upgrade program, plus 6 new pages presenting: (a)  Details of our Shaft Material, (b)  Hardness of Our Clutch Surface, (c)  Shaft Toughness,   (d)  Why Stress Matters, (e)  Upper Bearing Details,  and (f) Pictures of the EPI Secondary Upgrade.
  4. Added lots of new material to the page which covers the detailed analysis of the ProDrive belt System.
  5. Added a new page to rebut the Errors published on the ProDrive website after our technical presentation at Homer's-2004.
  6. Added a new page ( Properties of Belt Drives ) to the Mechanical Basics section and added new material to Stress and Strain and Metal Fatigue.
  7. Added lots of new information on the T-62 Turbine Conversion for the Rotorway helicopter.
  8. Added new information and pictures of the Phase-1 EPI  500-HP Aircraft V8 Engine.

05/24/04

  1. Added the EPI Reference Library and reference notations throughout the site.
  2. New Mechanical Basics sections on Velocity and Acceleration, Force and Friction, Stress and Strain, Metal Fatigue, Fretting Corrosion and Bearing Life.
  3. Additions to the PSRU section, including expanded presentations of Gear Information and Hy-Vo Chain Information, as well as pictures of the innards of the Mark-14 gearbox, two new propeller gearbox designs: the Mark-15 and Mark-16, and a new helicopter gearbox for swapping a turbine engine into a RotorWay 162.
  4. The analysis of the RotorWay Secondary Shaft failure problems has been substantially upgraded, with new pages, new analysis, new FEA with pictures, and major rewrites of previous pages. It includes a new presentation of the increased loading generated by the ProDrive™ toothbelt system, expanded analysis showing the V-belt, Factory Chain Drive, and ProDrive™ at the same Max Power and Cruise Power conditions, Bearing Failure Analysis, PLUS announcement and description of a new, economic solution to the RotorWay Secondary Shaft failure problems and removed reference to the previous design which included a clutch.

07/21/03

06/19/03

  • Minor wording revisions to several pages in the RotorWay section; also fixed numerous typos and removed incorrect price for a drive belt.

06/16/03

  • Technical and editorial revisions to add clarity to the presentation of the RotorWay drive failure problems.

06/15/03

  • Added an in-depth analysis of the alarming failure rate of the secondary drive system on the RotorWay Exec series of helicopters.

06/10/03

06/24/02

  • Added a new Main-Button category (SERVICE BULLETINS) and published all EPI service bulletins.

05/23/02

04/09/02

03/15/02

  • Added new pages (PROPELLER DAMAGE) on prop strikes; Added direct link button (left side of page) to the PROPELLER DAMAGE page.

11/20/01

  • Added "Next Subject" links to all PSRU TECHNOLOGY pages; Revised direct link buttons on left side of pages.

11/15/01

  1. Significant revisions to the PSRU OVERVIEW page to expand coverage of Link Chain Drives and announce a new EPI PSRU product;
  2. Addition of CHAIN DRIVE DESIGN ISSUES page.

09/03/01

  1. Added NEAT LINKS page.
  2. Added page which explains the relationship between POWER and TORQUE.

09/01/01

  1. Added REVISION HISTORY page; Expanded COMPANY BACKGROUND page; Compressed CEO RESUME and moved it to separate page under COMPANY BACKGROUND.
  2. Rewrote introduction to AIRCRAFT V8 DEVELOPMENT section, with new pages on TORSIONAL ABSORBERS and THE FUTURE OF 100-LL FUEL.
  3. Replaced entire PSRU TECHNOLOGY section with expanded presentations of VIBRATION FUNDAMENTALS, TORSIONAL EXCITATION, TRANSMISSIBILITY, and COMPONENT LOADS.
  4. Expanded AIRCRAFT ENGINE CONVERSIONS section, with new pages on ENGINE INSTALLATION ISSUES, ENGINE MOUNT DESIGN and WHIRL MODE.