Courtesy of the Manufacturer
April 12, 2010
Contributers: Steve Baur, Justin Cesler

So you've been driving your Fox-body or SN-95 Mustang for a few years now, and you realized that over the course of your 45-60 minute commute, you've grown tired of the lumpy camshaft's propensity for surging and bucking, which is due, thanks in part, to the relatively ancient computer that can't make sense of the high-overlap camshaft's shenanigans. But common sense strikes and you also realize that you cannot live with stock 5.0L power. What does one do in this predicament? Build a 351 Windsor engine.

With the Fox-body's weight bias already pretty fubar with the 5.0L, adding some 60 extra pounds to the front certainly won't help in this department, but you can cancel out much of that extra heft by using aluminum cylinder heads, and a tubular front K-member and A-arms.

It's not a necessary expense though. If you're just looking for that extra surge of power when getting onto the freeway or interstate, and not planning on carving up the turns, you probably won't notice the weight

What the 351 offers over a 5.0L or 302-based stroker is a better rod ratio, a stronger block, and the ability to go up in displacement for even more power and torque. The sizeable increase in displacement will also offer more average torque and horsepower than a 302, and will allow us to do it without a lumpy cam profile. That is our goal for this budget-minded buildup.

Looking across the street at what the General offered in late-model F-bodies, the 346ci LS1 offered up some 325 hp (350 in the Corvette with a better exhaust), while the LS6 (346 ci) produced up to 405 hp thanks in part to better heads, intake, and camshaft specifications. We plan to put our Street Smart Windsor somewhere in this mix. While 400 hp would be very nice, we are somewhat limited with our camshaft options due to the stock pistons in the short-block.

Whereas the LS6 lifted the valves 0.550 inches, we'll be limited to about 0.500. One could make this up with the duration and lobe separation angle, but we intend to keep a stock idle and driveability characteristics, similar to the LS engines. If you want to add the hot cam and deal with the reduced driveability, then have at it, but a smooth idle and stock driveability are high priorities for this buildup, and the increased displacement should offer plenty of power and torque for us to have fun with on our daily commute.

The Foundation
Most people aren't going to sink a ton of money in an engine and not have it maxed out power wise, so we felt it was necessary to keep the costs down wherever possible, starting with the short-block. Advertised for just $999, Latemodel Restoration Supply's (LRS) budget 351 starts with a late-model factory 351ci two-bolt-main engine block that was sent out for a stock rebuild. The rotating assembly is all factory cast parts, from the crank to the rods and pistons. There are no magic speed parts here-just your basic Blue Oval truck parts and a rebuild that should last 100,000 miles or more. It's definitely budget friendly, and will allow you to spend more money on the cylinder heads and camshaft, where it counts the most.

The Swap
Dropping a 351W into a Fox or SN-95 chassis isn't anything new, and a number of companies offer all of the parts you need to bolt it right into your Mustang without too much drama. Ford Racing Performance Parts, among others, offers an oil pan, oil pump pickup, and dipstick combination just for this application. The company also offers the brackets necessary to make your factory accessory drive system bolt right up. While ordering you short-block from LRS, you can order all of these parts as well. Other 351-specific parts you will need are an intake manifold, distributor, and exhaust headers.

A stock truck EFI distributor will get the job done if you can find one, otherwise you'll have to look to the aftermarket. Pro Comp, Accel, and MSD all offer a drop-in unit that utilizes the factory TFI ignition module. Headers for the 351W can be found in both shorty style and long-tube versions; Trick Flow Specialties and Edelbrock both offer 5.8L intake manifolds that are designed to work with factory fuel injection systems. There are also carburetor manifolds that have been converted for fuel injection, but we're looking for something that resembles the factory intake manifold.