Dear Engine Enthusiast,

Engine simulation technology has had taken substantial steps forward in modeling power over the last few years, and Dynomation-5 is leading the way.

Dynomation-5 is the ONLY professional-level engine simulation that was designed— from the ground-up—to be easy to use for anyone! Dynomation-5 lets you build and test engine component combinations in minutes, not hours or days as some other software products require. Dynomation-5 lets you be productive right away!

Dynomation-5 helps you to build better engines on a tighter budget! Building the right combination the first time will save you a bundle...let your competitors make the costly mistakes.

And one of the best features of owning Dynomation-5 is the support you'll receive from Motion Software. Since Dynomation-5 was released earlier this year, users have received hundreds of FREE updates and added features...just by letting us know their needs (yes, we really listen to our customers). Join the team and let us work for you!

Larry Atherton
President
Motion Software, Inc.

Profile Files vs 10-Point CamFiles
(or, what's this all about
10-point files, anyway?)

Dynomation-5 is very capable of modeling and testing cam timing. It models valve motion from a set of data points that are either derived from direct cam measurement (a Cam Profile File) or is extrapolated from event-timing data (a 10-Point CamFile), often published by the cam manufacturer. If you have lobe-profile data for the cam you wish to model, Dynomation-5 can use this to most accurately simulate valve motion. However, if you wish to alter cam timing—perhaps to test the affects of different IVC (Intake Valve Closing) points—or if you don't have profile data, 10-Point cam timing is your answer.

10-Point Timing is a term coined by our software developers that indicates a particular camshaft is being modeled from 10 data points: The Intake and Exhaust Opening and Closing points specified at both the Seat-to-Seat and 0.050-inch lift points  (that's 8 points) and the maximum lift of each lobe (that's a total of 10 points of data). While this may be a small number of points to define an entire camshaft profile, by using a few clever mathematical tricks, you can not only reasonably extrapolate a valve-motion curve from this data, you can also closely estimate valve acceleration rates.

There are two main advantages to using 10-Point cam data: 1) If you don't have profile data, it still allows you to model a particular camshaft, and 2) even if you have profile data, converting to a 10-point set allows you to alter any timing point and determine the affects on engine output. With a profile this is not possible, since the timing points are "locked" in the profile. (You can change lobe-centerlines and, for DOHC engines, intake and exhaust centerlines, but individual timing points and overall lift are "fixed" in a cam profile).

Dynomation-5 offers powerful tools to help you get the most from 10-point cam data sets. You can manually alter any event timing, you can search and test any of the 6000+ 10-point camfiles supplied with Dynomation-5, or you can use the exclusive built-in Iterator™ to automatically test cam timing and find what works in your application.

There is much more on 10-Point and Profile cam timing, valve motion, and how it is used in Dynomation-5 in the Users Manual.

Feel free to send any comments or questions to: latherton
@motionsoftware.com

User Manual Update

Our writers are busily working on an update to the Dynomation-5 User Manual that will cover the hundreds of updates and changes that have been rolled out to Dynomation-5 users over the past couple of months. We are planning on distributing a fully-updated user manual via Motion's Automatic Updater within the next few weeks. It will cover all the changes made in the last three Dynomation-5 updates.

In the future, we will make every attempt to supply an updated User Manual as soon as possible after Dynomation-5 updates have been released.

Upgrade To Version 5

If you haven't yet upgraded to Dynomation-5 from version 4 or earlier DOS versions, now is the time. Special discount pricing of $99 for version 4-to-5 upgrades (and $199 for DOS-to-5 upgrades) will expire the end of this month. Check out the pricing HERE and don't miss out on the super-low price upgrade opportunity!

Your E-Newsletter
Subscription

Motion Software respects the personal nature of email communication. Every effort is made to provide information that may be of value to you. If you do not wish to receive this E-Newsletter in the future, just send a return email and mention unsubscribe. You will be removed from our mailing list.

Dynomation-5 takes full advantage of the latest technologies in WindowsXP and Windows Vista.
Dynomation-5 is also fully compatible with Windows98/Me/2000 versions.

  Powerful Enhancements Distributed To
    Dynomation-5 Owners FREE!

Dynomation-5.03.0608: Perhaps one of the most powerful features of Dynomation-5 is the feedback that we get from our customers and the rapid way we incorporate their suggestions into new features and enhancements. The latest version 5.030608 update to Dynomation-5 has more than 100 improvements that came directly from our customers! Here are some of the enchantments that Dynomation-5 owners are using now:

• 2- and 3-Valve-Per-Port improved accuracy
• Improved Cam-Profile Import with new graphs and data displays that assist in lobe selection and speed profile import
• Camshaft Component Category improved for both Profile and 10-Point CamFiles. Selections are easier and more accurate.
• Reliably build and test more exhaust headers
• Improved simulation stability and improved calculation speed
• Expanded ranges for bore and stroke permit modeling
  larger engines (tractor and industrial)
• I.R. Runner flow models improved for higher accuracy,
  includes improvements for all Independent-Runner applications
• NEW! Save partially-completed engine buildup
• NEW! Export RPM-Based Data to text file and spreadsheets
• NEW! Use Arrow Keys to move graph reticule lines

Motion Updater: Dynomation-5 customers can upgrade their software automatically by simply selecting "Check For New Version" from the HELP menu. If they forget, Dynomation-5 will remind them once a month to get the latest version. And it's all FREE; part of the benefits of joining the Dynomation-5 Team.

  Cosworth YAC 2.0L—Dynomation-5 Testbed
     Part 1, The Engine Overview

   I recently had the pleasure of meeting Steve Jennings of Jennings Racing (www.sjenningsracing.com). Jennings and his two sons moved from California to Utah and located their shop not far from the new Miller Motorsports Park in Toole. Jennings Racing is well known for winning engine combinations, especially their Cosworth YAC and BD racing engines.
   Around this time, I was completing the final design of the latest updates to Dynomation-5 (for version 5.03.0528). Since my son Kyle works at Jennings shop and was in the process of building a Cosworth YAC racing engine, this seem like a perfect opportunity to directly test some of the simulation updates. We approached Steve Jennings with the idea, and he graciously allowed Motion Software, Inc., to use this engine as a baseline testbed. This article is about this race engine, the testing procedure, and how we used the results to assist in validating new multi-valve-per-port modeling now incorporated in Dynomation-5.

A “DYNOMATION-TEST” ENGINE

   The Cosworth model YAC engine is based on a 4-cylinder 2.0L Ford block. To improve reliability and overall performance, Jennings designed a replacement cast-aluminum block that they fully machine in their shop. YAC engines typically use a bore diameter of 3.587-inch and a stroke of 3.033-inch, which creates the total displacement of a little over 2.0L. Equipped with dry sump oiling, these engines were originally built for the American Cities Race League (ACRL/CRS) racing series as well as the Sport Car Club of America (SCCA) Sports 2000 series.
   Our test engine started out in “stock” configuration, delivered by a customer that wished to have Jennings completely rebuild the engine for an extended road-racing application. To build a reliable high-rpm engine, most of the stock rotating assembly had to be either replaced or completely reworked. The stock connecting rods were the first to go, replaced by Carrillo I-beam, 5.208-inch steel rods. The original pistons had substantial domes that closely fit the pentroof chambers, creating an overall compression ratio of 13.6:1. Since this engine was going to run at nearly 100% full-power output for more than 2000 miles (roughly the equivalent of one race season), Jennings believed it was essential to reduce the compression ratio to 10.5:1. To accomplish this, the domed pistons were replaced with a lighter, flat-top design that incorporate a thermal-barrier coating. The ceramic that Jennings chose keeps the combustion energy working as pressure on the pistons rather than allowing a lot of that heat to escape through piston surfaces.
   The head is a stock Cosworth casting, using four valves with dual-overhead, direct-acting camshafts. The stock sodium-filled valves were replaced with custom parts from REV (Racing Engine Valves, Inc.). Intake valves are 1.380-inch diameter and the exhaust valves measure 1.218-inch. The stock valve seats were replaced with Mar-Tite inserts. The ports are “stock” and quite restrictive with an opening diameter of 1.4-inches, an area of 1.55-sqin, while the smallest port restriction occurring near the valve guide has an area of less than 1-sqin (a port mold can be taken to determine the exact minimum restriction areas but was not considered necessary in this case). Per the customer’s request (and rule limitations) no porting or other alterations were done, so port dimensions remained unchanged on both the intake and exhaust passages.
   The camshaft (rules, again) is a stock profile with intake and exhaust duration of a minuscule 241.3 degrees. The intake-centerline angle was set at 110 degrees, opening the intake opening at 9.4 degrees BTDC and closing it at 51.9 degrees ABDC. The maximum intake valve lift is 0.373-inches. The exhaust centerline was also set at 110 degrees, positioning exhaust valve opening at 49.5 degrees BBDC and closing at 11.8 degrees ATDC. Maximum exhaust lift is .371-inches. This cam timing generates 21.2 degrees of valve overlap, a typical figure for the rule-mandated “stock” setup.
   The intake system is comprised of individual-runner, 8-inch passages that pass though two, dual-throat, 45-mm DCOE Weber side-draft carburetors with 1.772-inch diameter “butterfly” throttles blades. The runners also incorporate short, 2-inch diameter “bells” enclosed in a typical intake-scoop housing. A low-restriction filter element is mounted in the scoop to keep debris out of the engine.
   The exhaust system is a tried-and-true header design with a standard four-into-one collector. The header pipes are 2.0-inch diameter and 34-inches in length. The collector is 7.25-inches long and tapers to a 2.25-inch exit. The remaining 28-inch exhaust pipe maintains a 2.25-inch size to its exit to at atmosphere.
   The ignition system was upgraded to a Crane system and the timing was fixed at 20 degrees.
   When the engine build-up was complete, a break-in session was scheduled on one of Jennings dynos. The dyno chosen was a Stuska water-brake system with Depac data acquisition electronics (this is his smallest dyno cell, but is often chosen for engine break-in and initial testing). Since the overall engine-design focus was long-term reliability, Jennings’ son, Cliff, explained that the components selected (particularly the piston rings) usually take about 500 miles to fully seat, providing optimum power for the remaining 1500 miles of the racing season. Initial break-in is an essential part of maintaining reliability and ensuring peak performance, so it is very carefully performed and controlled on the dyno. This durable Cosworth powerplant can be raced season after season, essentially indefinitely, as long as top-quality rebuilds are performed between seasons!
   When the initial break-in cycle was complete, a few power pulls generated only about 170-hp. But a closer look at the customer’s carburetors indicated that the jetting was nowhere near ideal. After re-jetting and tweaking the Webers, the air/fuel ratio measured on the dyno indicated a lambda of .85 to .90 (between 12.5 and 13.2 to 1 for gasoline). The correct jetting allowed the engine to produce 192-hp and 172-lbft of torque, a normal power level for this type of engine.

The simulation and analysis of the Cosworth engine will continue in the next issue of this E-Newsletter.

ABOUT THE AUTHOR: Brent Erickson is Motion Software's Lead Programmer on the Dynomation-5 project. Brent’s love of programming and automobiles started when he was 12 yeas old. For 25 years Brent developed more than 70 computer games including several racing simulations. For the last 10 years Brent’s skills have evolved from games to the world of high-end simulations enjoyed by many Motion Software customers.

Copyright © 2008 Motion Software, Inc. All Rights Reserved. Dynomation™ and Motion Software™ are trademarks of Motion Software, Inc. All other trademarks are the sole property of their respective owners.
The text, photographs, drawings, and other artwork (hereafter referred to as information) contained in this publication is provided without any warranty as to its usability or performance. Specific system configurations and the applicability of described procedures both in software and in real-world conditions—and the qualifications of individual readers—are beyond the control of the publisher, therefore the publisher disclaims all liability, either expressed or implied, for use of the information in this publication. All risk for its use is entirely assumed by the purchaser/user/reader. In no event shall Motion Software, Inc., be liable for any indirect, special, or consequential damages, including but not limited to personal injury or any other damages, arising out of the use or misuse of any information in this publication. This E-Newsletter is an independent publication of Motion Software, Inc. The publisher (Motion Software, Inc.) reserves the right to revise this publication or change its content without obligation to notify any persons of such revisions or changes.