As mentioned earlier, the SSRE gang turns to a specially prepared Dart low-deck iron engine block to begin its run up to 598 cubes--an aluminum engine block is optional. The bores are enlarged to 4.600 inches, while the Eagle 4340 steel crankshaft offers a 4.500-inch stroke. The standard connecting rods are also sourced from Eagle and are 6.535 inches long. For those looking to add nitrous or step up the rotating assembly, a Callies crankshaft and connecting rods are available as upgrades.
There aren't too many tricks to running 93-octane pump gas other than keeping the compression ratio in check as well as the proper camshaft. SSRE limits this big-block to 10.95:1 and the JE pistons feature a coated side-skirt for oil control and reduced friction.
The short-block is fairly typical for an Ultra Street 598ci engine, and the difference between Twisted and the Big Dawg 598 (775 hp version) resides on the topside. Airflow is the key to more power and SSRE adds Brodix 383 Head Hunter oval port heads that are fully CNC-ported. A Brodix Big Mouth Dominator intake manifold is on top and comes port-matched.
A mechanical/solid roller camshaft controls the massive 2.35-inch intake and 1.85-inch exhaust valves. The specs were specifically designed by SSRE for this engine, and as Scott puts it, "The cam gives the engine a nice strong idle and great street manners, but it still makes the power."
The cam features a 114-degree lobe separation and the intake lobe lift is 0.739-inch each while an octave of exhaust valves are opened slightly more with a 0.741-inch lift. The duration is a healthy 269 degrees for the intake and 276 degrees for the exhaust.
Some enthusiasts might ponder the use of a camshaft with more exhaust lobe lift than the intake side, as typical cams are the other way around. We were curious, too and Scott gave us his typical smirk and said the camshaft was one of the reasons they sell packages--everything is designed to work together, including obscure cam profiles. He used a combination of scenarios to come up the specs and it goes back to pump gasoline limits and the efficiency of the Brodix heads. The team tried several different cam profiles using conventional and unconventional thinking, with that camshaft providing the right power and drivability. Other cams made a little more power, but it came at the detriment of drivability, a factor Scott wasn't willing to compromise for a gain in peak horsepower.
The Twisted retails for $15,950, less carb and ignition, but each is available from SSRE. An added bonus to the base price tag is free shipping in the continental 48 states, and a 2-year warranty. Shafiroff has the ability to ship overseas anywhere in the world.
Shafiroff bolted the engine to the dyno and added one of the SSRE blueprinted and calibrated Holley Dominator kits to the top of the bullet for the final results. He suggested that particular carburetor for this application and it is an optional item that will increase the base price. As photographed for this story with the Holley 1150 Dominator carb package (tuned and installed), MSD ignition package, Hippo lifters, composite distributor gear, Cometic head gaskets, ATI balancer, and sheetmetal valve covers, the total package price is $18,340.
As for our little bet--the Twisted screamed on the DTS dyno as it unleashed an astonishing 920 hp at 6,300 rpm and a staggering 809 lb-ft of torque at 5,500 rpm. Once again, SSRE proved bigger is better and we quickly anteed up our one-dollar bet on Scott's 900-plus prediction.