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Broadway Limited Imports Paragon3 N scale EMD SD70ACe diesel

Read this review from the September 2020 Model Railroader
Broadway Limited Imports Paragon3 N scale EMD SD70ACe diesel

A 4,300 hp, six-axle answer to 20th-century pollution reduction guidelines is the latest locomotive to join Broadway Limited Imports’ N scale roster. More than 1,100 SD70ACe diesels were built and sold over the span of 11 years, eventually seeing service on almost every Class 1 railroad in North America and some regionals. Broadway Limited’s version features an accurately dimensioned body, a smooth-running flywheel-equipped motor, and a powerful Paragon3 Digital Command Control (DCC) sound decoder with BLI’s exclusive Rolling Thunder sound system.

Running greener. When the U.S. Environmental Protection Agency (EPA) announced more stringent Tier 2 emissions standards would be phased in beginning in 2004, General Motors Electro-Motive Division started designing a new locomotive based on its SD70MAC design. EMD designers tweaked the 16-710 diesel engine to meet these guidelines, dubbing the upgraded engine the 16-710-G3C-T2.

In 2015, the EPA imposed Tier 4 emissions standards for diesel locomotives. The SD70ACe’s motor couldn’t be upgraded to match this new, stricter standard, so EMD, which in 2005 had been spun off from GM as Electro-Motive Diesel, developed its successor, the SD70ACe-T4, which runs on the 12-cylinder, four-stroke EMD 12-1010 “J”-series engine.

However, railroads can continue to use the Tier 3-compliant SD70ACe using credits earned by meeting and exceeding previous emissions reduction targets. Only two U.S. railroads, Union Pacific and Norfolk Southern, own such “Tier 4 credit units.” These are the locomotives represented by BLI’s N scale models.

Electro-Motive Diesel is still building SD70ACe diesels in Mexico for export; units sold to Kansas City Southern de Mexico, Ferromex, and Ferrosur are restricted to operation in Mexico and can’t cross the U.S. border.

The once over. Our review sample is decorated for Norfolk Southern no. 1112, a Tier 4 credit unit built in 2014. I was able to find numerous photos of the prototype online. The placement of details, paint, and warning stickers on the model almost all matched the photos. The exceptions were the front and rear stair handrails, which on the prototype are painted yellow. That’s easily rectified with a bit of paint designed to stick to flexible plastic, like Pactra Racing Finish. Also, in some early photos, what look like white rectangular stick-on decals protect the pilot where the m.u. hose ends hang, but those were gone in a few months.

The body shell’s satin-black paint job is smooth and even. The white printing, from the thoroughbred logo on the long hood to the stripe on the sill, is straight, sharp, and opaque. There are voids along panel lines in the herald, though, and the warning labels on the hood doors are too small to be legible.

Most details, such as grab irons and windshield wipers, are molded into the one-piece body shell, though there are a few separately added details, like the horn, m.u. hoses, cab sunshades, and uncoupling levers. The shell is finely molded, with sharp definition in the seams and grills. The handrails are close to scale thickness and include see-through chain links on the front and rear.

All the dimensions I checked, including the wheelbase, matched those on diagrams published in the November 2004 Model Railroader. The Magne-Matic couplers were both mounted at the correct height. The blackened metal wheelsets, on the other hand, were gauged slightly tight according to the National Model Railroad Association standards gauge. That slight discrepancy didn’t give the engine any trouble when traversing the Peco medium-­radius turnouts and 13" curves of our N scale Canadian Canyons layout, though.

A five-pole open-frame motor and its dual brass flywheels are enclosed by the die-cast-metal frame. The speaker is concealed in the fuel tank.

Under the hood. After removing the coupler boxes, I could lift off the body shell. A five-pole motor and two brass flywheels nestle in a black-painted die-cast metal frame, on top of which sits the DCC decoder. The thick, black wire on top of the decoder is the antenna for the BLI Rolling Thunder system, which I’ll describe later. On either end of the frame are the golden-white surface-mount light-emitting diodes that illuminate the headlights and the ditch lights on the front pilot deck. A sugar-cube speaker is enclosed behind a grille under the plastic fuel tank.

Removing the body shell also gives a better view of the locomotive’s well detailed EMD HTCR-II high-traction, radial-steering trucks. Also visible are superbly rendered details that include the molded wiring runs and piping that are routed along the frame under the sills, an innovation that on the prototype improved maintenance access.

Test track. I tested the locomotive first under Digital Command Control, using a Model Rectifier Corp. Prodigy Advance2 system. Pressing function key F9 played a startup sound sequence that began, amusingly, with the crunch of boots on stone ballast and the slamming of a cab door. Pressing F9 again triggered a shutdown sequence.

The sounds of the diesel engine’s RPMs cycled up and down with the throttle setting. I soon discovered that F5 and F6 let me notch the engine sounds up and down independently of the locomotive’s speed, which is great for simulating realistic engine sounds when laboring with a heavy train in notch 8 or coasting down a long grade in notch 1. Function key F1 toggled the bell on and off, F2 blew the horn, and F3 turned the dynamic brake fan sound on and off. Key F4 turned on an air compressor sound, F7 controlled the ditch lights independently from the directional headlights, and F8 muted and unmuted all sounds. Other function keys, as outlined in the included printed instruction manual, played radio chatter, a grade crossing horn signal, and various background sounds.

The locomotive responded smoothly at slow speeds, rolling at less than 5 scale mph in speed step 1. At the other end of the throttle, it zipped along at 112 scale mph, well above the prototype’s top speed of 70 mph. I set Configuration Variable (CV) 5 to a value of 70 – a simple adjustment – and was rewarded with a prototypical top speed of 71 scale mph.

Before making that change, though, I tested the unadjusted locomotive under direct-current (DC) control, using an Athearn power pack. I heard the start-up sequence when the throttle reached 8.25V. The engine idled smoothly until I increased the voltage to 8.75V, at which point engine RPM notched up and the locomotive rolled at 6.2 scale mph. It topped out at 88 scale mph at 13V.

The only sound effects available in DC mode were the diesel engine, which notched up and down in RPM with the throttle, and a brake squeal that sounded automatically when I reduced the throttle quickly. I found it easy to reduce speed, stop, and reverse directions without the sound cutting out.

Rolling Thunder. The locomotive’s Paragon3 sound decoder is equipped with a transmitter for Rolling Thunder, BLI’s subwoofer sound system. This plug-and-play product works with both DC and DCC layouts, as we noted in our review in the March 2016 issue.

I connected our Rolling Thunder system to our workshop test track. As the SD70ACe approached the receiver, low bass sounds of the engine and horn were picked up and played through the subwoofer. Such realistic rumbling simulates the awesome feeling of standing trackside as a 1:1 SD70ACe rolls by.

A modern workhorse. If you model big-time, modern-day railroading, your model railroad needs an SD70ACe or three, especially if you’re modeling the NS, UP, or BNSF Ry. (a road name that I hope will be coming soon). This smooth running, well-tooled model is a worthy addition to any contemporary N scale roster.

BLI Paragon3 N scale EMD SD70ACe diesel performance chart
Facts and features
Price: $249.99
Broadway Limited Imports
9 East Tower Circle
Ormond Beach, FL 32174
Era: 2004 to present (as decorated, 2014-)
Road names: Norfolk Southern (Thoroughbred scheme in two numbers and heritage schemes in one number each: Erie, New York Central, Penn Central, and Reading Co.) and Union Pacific (Building America scheme in two numbers, George Bush 41 livery in one number, and heritage schemes in one number each: Chicago & North Western, Denver & Rio Grande Western, Missouri-Kansas-Texas, Missouri Pacific, Southern Pacific, and Western Pacific); also available undecorated.
• All-wheel drive and electrical pickup
• Blackened metal wheels, gauged slightly tight
• Dual-mode Paragon3 DCC sound decoder with Rolling Thunder
• Golden-white light-emitting-diode (LED) lighting
• Macro recording and playback capability
• Magne-Matic magnetic knuckle couplers, mounted at correct height
• Minimum radius: 9.75"
• Skew-wound motor with dual flywheels
• Weight: 3.6 ounces

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