Muscle Mustangs & Fast Fords
Ford Mustang 351 Windsor Engine Replacement Part 2
We Show You What It Takes To Drop A 351 Windsor Engine Into Your Fox-Body. It's Not That Difficult. Trust Us.
As popular as the 5.0L pushrod engine is (we actually have to separate it from the new overhead-cam engine now), old school hot-rodders know that bigger cubes means bigger power. If a 302 is good, a 351 must be better, right? They're not wrong, and we intend to show just that with our Street Smart Windsor build.
Sure, your author takes his hits around the office from those who make fun of his need to have stock driveability, but then again, none of them drive as much (104 miles every day). After living with lopey cams, surging throttles, and bucking drivetrains, it's time to build a better mousetrap.
Last month, we set the goal for 350-400 flywheel horsepower with a stock idle, and we decided to use a budget 351 Windsor short-block from Latemodel Restoration as the foundation. The $999 Windsor wonder doesn't feature one trick or high-performance part, but it offers cubes, a good rod ratio that will ensure longevity, and the ability to go even larger in displacement if needed.
Right now you're probably thinking, what kind of Mustang enthusiast is satisfied with a mere 350 hp when there are 600-rwhp GT500s running around? Well, not all of us have $35,000 for a GT500 and another $6,000 for mods. And you'd be more than surprised at how fast a 3,100-pound car is on the street with 350 hp and as much torque. Just ask any Corvette Z06 owner. During the project Stolen Goods Cobra build, your author also realized that naturally aspirated street power is trouble free, and 350-400 hp in a Fox-body Mustang is more than enough to overpower the tires at any given moment. You can do this with a stock idle, saving yourself a few dollars, and gray hairs too.
Last month we talked about our options and possible choices for engine components aside from the aforementioned short-block from LRS. We went ahead with the RHS cylinder heads. RHS's Pro Action 200cc inline valve heads offer enough airflow to support our 359-cube motor. According to the markings on our pistons, our short-block has been bored 0.040-inch over on the cylinder bores. When combined with the 3.500-inch stroke, that equates to 358.93 ci.
We also went with Comp Cams' Ultra Gold aluminum roller rocker arms and the custom camshaft grind that we detailed. Duration checks in at 212/218 at 0.050-inch lift, with lift figures of 0.513 inch on both valves. Cut with a 114-degree lobe separation angle, this grind should give us the smooth idle we want, while maximizing the valve lift for our combination. After talking over the intake manifold choices and specifications with Comp Cams' Chris Mays, we went with the Trick Flow Specialties R-Series EFI manifold for the 5.8L engine. We also specified the 90mm throttle body opening so we could try larger throttle bodies down the road, but for now, we'll be using one of Trick Flow's 75mm units.
An area that we didn't cover in the first installment is the mass air meter and intake tract. For that, we turned to induction guru Rick Anderson at Anderson Ford Motorsport. We often consult with Mr. Anderson: His numerous years of experience in the Mustang hobby, and countless hours on the dyno and at the track, have taught him what works and what doesn't. To fulfill Street Smart Windsor's airflow needs, he recommended one of Anderson Ford Motorsport's Power Pipes; he also recommended Abaco Performance's DBX97b programmable mass air meter.
The DBX97b mass air meter measures-you guessed it-97mm, and features a bell-mouthed entry for maximum incoming airflow. All Abaco meters are digital-based, and can be programmed to meet your engine's airflow and fuel injector requirements. They also feature a patent-pending digital response filter that helps filter out "noise" in the airflow signal, which is said to improve driveability-there's that darn word again. The meter doesn't suffer ill effects from clocking the housing in a certain orientation, thanks to its multiple sensing elements. You can also move it from Mustang to Mustang just by switching the harness and the program inside the meter, which holds up to 10 different programs.