We feature a lot of engine builds in Modified Mustangs & Fords and they invariably find themselves resting between the fender aprons of this or that Ford hot rod, destined to offer improved acceleration via an increase in available horsepower. Torque, however, is what moves those vehicles and pushes you into the seat at the crack of the throttle, and it's torque that is important when you're pulling a trailer. Our latest engine build comes from B2 Motorsports, and it was built primarily for great torque production, as it would be dropped into a '52 Ford F1 that also pulls a car trailer when hunting for other classic cars.
"This motor was basically opposite from what we usually do," says B2 Motorsports Brent Lykins. "It's bound for a '52 Ford F1 pickup, which is going to be turned into a daily driver as well as a tow vehicle. With that in mind, emphasis was placed on running on 87-octane fuel, having high engine vacuum, a clean idle, and having enough torque at low rpm to pull a trailer. The truck's owner often pulls an enclosed trailer, and with his 8,000-pound load estimate, we needed some torque."
Lykins picked out a stroked Windsor combination that would offer big torque via extra displacement, while being relatively compact in its small-block package. While perfect for its intended use, big torque engines like this one are just at home in heavier classics such as Fairlanes, Galaxies, and even later-model Mustangs. Here's how it went together.
1. The block is a factory roller block, bored 0.030-inch over stock. The bores were honed with torque plates, the decks were square decked with a BHJ fixture, and the mains were align-honed with ARP bolts.
2. Since it was a factory roller block, B2 Motorsports’ Brent Lykins could reuse a standard-base-circle camshaft, and use the OEM lifters and spider retainer.
3. The rotating assembly consists of a Scat 9000 series crankshaft with a 4.000-inch stroke. Rods were forged Scat I-beams, with a 6-inch length and an SBC rod journal. Pistons were Keith Black hypereutectic pistons with floating wrist pins. This combination should work well together, since the crank counterweights were designed for a 6-inch rod.
4. During mock-up, Lykins found that the counterweights came within 0.012- to 0.013-inch of the piston’s wristpin boss; not acceptable in his mind. Once that was found, the crank was put in a lathe with an offset cam drive, and the counterweights were turned down so that more clearance was achieved. “This goes to show that parts that are designed to work with each other don’t always work with each other, and each builder needs to check every single detail,” Lykins noted.
5. The camshaft is a billet steel Comp Cams hydraulic roller, which Lykins chose because of its zero maintenance and lack of break-in procedure attributes. While the engine combination comes out to 408 cubic inches, the single-pattern camshaft features a very short duration of 218/218 at 0.050. Lobe separation angle was at 112 and the intake centerline was put on a 108 to lower the dynamic compression ratio (again, good for when the engine is being lugged or at WOT at low rpm). Lift is 0.560 for both intake and exhaust, which is right there in the moderate lift range for performance and reliability. “The short duration results in an excellent torque curve with gobs of power and torque available at low rpm, while still being able to pull to 5,000 rpm,” says Lykins.
6. Lykins chose this combination to provide an extremely long life, noting that the hypereutectic pistons do not require much piston/cylinder clearance, which will minimize piston rock and increase stability. “The shorter rod also lends itself toward reliability and also some more hang time at TDC at a lower rpm,” he told us. “Keith Black pistons have the top ring very close to the crown of the piston, so the rings tend to need more end gap. For a towing application, where the engine could be in a position to be ‘lugged’ or at WOT at lower rpm, that end gap turned out to be 0.032-inch, a lot more than your typical 0.016- to 0.018-inch for a small-bore Windsor. The piston rings were 5⁄64, 5⁄64, 3⁄16, which didn’t contribute as far as performance, but they were very “dependable” rings with standard tensions...again, that’s needed for our daily driver.”
7. The cylinder heads are RHS 200cc aluminum heads. Lykins stated that they are great performers and with the small valve sizes and small port volumes, they also offer great velocity, which is good for low-rpm response.
8. The heads were ordered assembled, but they were disassembled so that each part could be checked. Valve guides, spring install height, and more were checked. Spring pressures came in at 150- to 350-lb/in. Shadowing the springs were a set of Comp Cams aluminum full roller rockers at a 1.6 rocker ratio. Here, you can see Lykins has installed a piston-to-valve checker spring on the exhaust valve of the head.
9. Piston-to-vale clearance checked out at 0.340-inch on the intake and 0.200-inch on the exhaust side while on the 108-degree intake centerline.
10. Lykins installed the camshaft four degrees advanced using this double roller timing chain from Ford Racing.