DYNO-MAX Version 9.37…

(the summer 2005 update to DYNO-MAX 2000 “Pro”) will be available in late June. Several user requested enhancements are included as part of this release. A few of the new features added in Version 9.39 include:

Custom Console Button Text -“Pro” users may now re-label their consoles control buttons. This makes it easier to support custom relay functions and non-English languages.

Overlay Data Points Averaging & Difference -now supports “Synch Data Points” even in time averaging mode. This “Pro” feature (to help align the controlling X-axis references) was formerly only available during Step Mode graphing.

“Automatically show Graph...” -preference has been added. This forces your customized graph (and/or data points) to immediately display upon a test's completion. This new preference is in addition to DYNO-MAX's existing controls for automating the printing of a completed run's graph or data points.

Real-Time Trace Chart overlaying -is now supported in the “Pro” version. This allows selecting any saved .run file as the chart baseline for subsequent tests. Either the scrolling or fixed X-axis trace chart modes may be used during real-time overlaying.

PC's “Scroll Lock” key -will now also toggle the “Test Completed” message off of the Trace Chart. This allows more closely examining lines (i.e. overlays) that fall under the text.

“Automatically press Brake Button...” -checkbox added to the Automated Test Wizard (for the Road Sweep and Road Course tabs). It supports automating the activation of a chassis dyno's end of test braking.

Free 9.69 EEPROM Upgrade!

DYNOmite-Pro users can upgrade to this version -at no charge! It includes both minor bug fixes and several controller related enhancements. (See our DYNOmite Web Support site for more details).

1) For DYNOmite-Pro's with the LCD option installed, additional Wide Band AFR O2 module calibrations are now available (including methanol and ethanol support).

2) During power-up, the DYNOmite has always tried to re-synchronize with any attached Automated Electronic Load or Throttle Control device. This synchronization routine has now been enhanced to improve success -even with improperly powered-down control devices.

3) When toggling from manual to servo control modes (e.g. Knob to Hold) when no Engine RPM is present, the DYNOmite will do an automatic close -to re-synch.

4) At power-off, the DYNOmite now internally stores the last known Hold Set-Point as its power-up default.

5) A bug in EEPROM 9.62 has been fixed so that when using the Servo % Position modes, the DYNOmite will again automatically re-synch at the extreme travel limits.

Current DYNOmite-PRO board set owners that have their DYNO-MAX computer connected to the internet should use DYNO-MAX's “Electronics -Display DYNOmite Parameters -Check for Upgrade” button to automatically download and flash update to the 9.69 release -at no charge! If your DYNO-MAX computer is not on-line, see the DYNOmite Support section (or contact our technical support department) for information about obtaining this upgrade.

“What do dynamometer BSFC #'s tell me?”

Brake Specific Fuel Consumption (or BSFC) is the ratio between the engine's fuel mass consumption and the crankshaft power it is producing. This makes it both a valuable fuel efficiency indicator and one more useful tool in gauging an engine's state-of-tune.

In the USA, the fuel flow for BSFC calculations is normally expressed in pounds per hour (lb/hr) while the output units, of course, are in horsepower (Hp). So, our standard formula for BSFC becomes: lb/Hp-hr . For an engine producing 200 horsepower, while guzzling 100 pounds of gasoline per hour, the equation would yield 100/200 = 0.50 BSFC. Unlike AFR (Air/Fuel ratio) readings which only reveal the mixture, BSFC data represents the power provided per fuel unit. AFR and BSFC are not equivalent!

The beauty of BSFC #'s are that they remain similar over a wide range of engine sizes (assuming both are of similar mechanical design and compression ratio). For example, a tiny one cylinder 50cc four-stroke and a 454ci V8 might both have a BSFC ratio of

0.45 lb/Hp-hr (when optimally tuned) at their respective peak torque points. Thus, if either of these engine's were overly richened, its BSFC might climb into the 0.55 to 0.65 range (because the fuel flow in our equation will be going up as the power is going down).

Consider the above example on a dyno that only displays horsepower. Without the BSFC data, it is harder to know that a rich mixture engine is the reason for sub-par output. But, when you also have the BSFC numbers in front of you, it aims you at the cause.

BSFC values all follow a hooked curve. At idle they run much higher -due primarily to the closed throttle pumping losses and excessive camshaft overlap. Minimum BSFC #'s occur at about the peak torque operating rage -the most fuel efficient (per Hp) operating point for an engine. As RPM increases towards peak power, the BSFC rises again, since more fuel energy is consumed just overcoming the speed induced friction and breathing restrictions.

Below are sample BSFC ranges for several typical engine types. Note, these are provided to illustrate relative BSFC behavior only. Realize that any change that improves the mechanical efficiency of the engine (e.g. a dry sump oil pan, electric water pump, low tension rings, lighter oil, etc.) will also reduce its BSFC values!

Engine @ 1,000 @ Peak @ Peak Type RPM Torque Hp

4-stroke (low compression, carburetor) 0.62 0.47 0.52 4-stroke (high compression, carburetor) 0.60 0.42 0.47 4-stroke (high compression, closed loop) 0.52 0.35 0.42

4-stroke (supercharged, carburetor) 0.75 0.50 0.55

4-stroke (turbocharged, closed loop) 0.57 0.45 0.50

2-stroke (low compression, carburetor) 0.85 0.55 0.60 2-stroke (high compression, carburetor) 0.80 0.50 0.55

Diesel 4-stroke 0.35 0.25 0.30

Diesel 2-stroke 0.40 0.29 0.34

Recreational Motorsports

...located in Cedar Rapids, Iowa has been a full service performance machine shop and dynamometer facility since 1992. They specialize in ATVs, motorcycles, snowmobiles, and karts. Additionally, RM helps the local high school's electric car team and state college's SAE Baja car program (the dyno being a great learning tool for each of them). Today they own three DYNOmite systems -two with 9" absorbers (both straight vane and the latest toroidal flow units) plus a 7" kart unit.

Their facility boasts the professional 9' x 14' sound proofed cell shown below. Scott Minzenmeyer, president of Recreational Motorsports, says “The acoustical material on the walls and ceiling helps keep the noise level down throughout the entire building -it was a very good investment. With our custom universal dyno fixture and the Land & Sea DYNO-MAX “Pro” software we are able to handle any kind of testing the customer wants. This makes our dyno room into a very nice profit center.”

Those customers range from national champion garden tractor pullers and lawn mower racers to the electric car team -plus everything in-between. Scott revealed that they have many racers bringing in an assortment of pipes, carburetors, and an array of miscellaneous performance parts, just to see which combination works best. In many of these situations, all Scott's employees have to do is operate the dyno -the customers handle their own tuning -making for very easy work.

Another interesting project (for the Kart Dynamometer) is developing racing engines and a line of performance parts for their 120cc (mini) snowmobile business. Right now they are designing camshafts for these small engines. Scott has found that with their electronic load servo they are able to load the engines the same way every time. This allows isolating very small changes between cams -a big help in shortening the R& D cycle.

For more information you can call them at 319-365-5391, or visit their website at www.recmotor.com.

PO Box 96 North Salem, NH 03073