Black Widow V-8

DwightGiles-KenHurstWhen Ken Hurst's supercharged Challenger V-8 broke its crankshaft, he &  Dwight Giles and the late John Vlavianos knew it was time to improve the breed of model V-8. That was 7 years ago and at that time John made patterns and cast a number of blocks, heads and other parts of the new engine. Unfortunately, John passed away, Ken had to overcome a seriour illness, and time went on.

After Ken's recovery, he and Dwight started down the long road to making a working engine. John had created enough drawings and sketches to support his foundry work but not all details were worked out. It took a fairly long time to decide exactly how everything was going to work and then build operating bits and pieces. But the first engine was finally completed in August of this year and shown for the first time at the Western Engine and Model Exhibition (WEME) show the last weekend of August. As you might imagine, it was a hit, a very noisy hit I might say. Popular, too.

This new V-8 isn't too far dimension-wise from the Challenger V-8, but it is designed to comfortably handle the much higher power it develops compared to the Challenger. This first engine has a 1" bore and stroke but future engines will probably be 'bored out' to a 1-1/16". The engine features 5 main bearings all cast as part of the block. The crankshaft main bearings are 1/16" larger in diameter than the Challenger. The Wrist pins are enlarged to 7/32". None of these little changes seem like much but they make significant increases in stiffness and crankshaft support, exactly where the Challenger is weakest. The crankshaft is made from 4340 and the camshaft is machined from 4130 and heat treated to about 50-55 Rockwell C.

engine1The engine is designed to have pverhead valves so the lifter valley is closed at both ends. With the addition of the intake manifold, the valley is completely sealed. The valve train features billet roller rocket arms, reduced diameter pushrods and modified lifters to support high RPM operation. the cast aluminum oil pan holds twice as much oil as the Challenger and careful attention was made to insure oil could easily drain back from the upper reaches of the engine to the pan.

Why all the attention to making this V-8 so much huskier? One reason is that the engine is designed to be supercharged and the two-lobe supercharger makes a big contribution to power when it is installed (as compared to running the engine with the supercharger removed). The other reason is that Ken and Dwight plan to install their engines in 1/3rd scale radio-controlled cars and race them. Dwight has a '32 Ford coupe body and Ken has a '33 Willys coupe body waiting as they accumulate the running gear and other parts to assemble the cars. You can see Ken's Willys body with an unfinished engine next to it at www.nvbackflow.com/engines.

After building this prototype engine, Dwight made some detail changes to the pattern set and they were delivered to a commercial foundry for a first run. Four sets of heat-treated castings were returned to Ken and Dwight just before WEME where they were sold early in the show. The foundry is working on a second round of casting sets. Don Jones has modeled the engine in Solid Works, a 3D MCAD software, and completed a comprehensive set of drawings for the engine. You can expect Model Engine Builder magazine to publish articles on molding the custome spark plug wires and making the radiator fan in future issues.

If you want to build this engine, please contact Ken Hurst at This e-mail address is being protected from spambots. You need JavaScript enabled to view it for further information.

-Reprinted from Model Engine Builder magazine
copyright 2011 by Elmwood Publishing, Inc.