Part One
The writing was on the wall a couple of years ago: Ford's tooling for the N351 cylinder head casting was wearing out, and if something wasn't done, that casting stood a chance of going the way of the dodo bird.

The problem was the N351 head wasn't exactly a new design. Very few people use it for street applications anymore. But like the venerable Chevy 23-degree cast-iron head, the N351 is still the most popular option for Ford racers in any class that still has "Stock" somewhere in the name. In many classes, in fact, it's the only Ford head allowed. That head is a constant; engine builders and race series alike are familiar with it and its potential for power production. The recipes have all been worked out for making good racing between Chevys and Fords with the current packages, so you can imagine that many racers, engine builders and series owners were more than a bit nervous at the thought of the N351 going away.

But that was before Ford announced that it has recommitted itself to the Saturday night racer. And the manufacturer has backed up that claim with lots of new products for everyone from the circle track racers to drag racers. Of course, at Circle Track we're a bit partial to the stock car racers, so when Ford announced the new Boss 351 engine block and brand-new N351 cylinder head castings, we were interested. And of course, we wanted to provide you with a more in-depth look than a cut-and-paste of Ford's press release, so we hooked up with Ford and race engine builder Charlie's Automotive to detail a complete engine build specifically for NASCAR's Late Model Stock class with the new Ford block and heads.

In order to give you as much information as possible, this build will be broken into installments in the magazine. And since this is one of the first race builds anywhere with this block and heads we'll devote the first installment to taking an up-close look at Ford's new hardware.

The Block Ford got the ball rolling more than a year ago when it announced the completely new Boss 302 engine block. And since the Windsor 302 (that the Boss is based upon) and the Windsor 351 share so many dimensions, most felt it was only a matter of time before a Boss 351 became available. And now it is here with plenty of upgrades over the stock 351 Windsor that will make it attractive to race engine builders.

Previously, Ford has offered many different versions of the Windsor to fit the needs of different racing classes. The Boss 351 is designed with what Ford calls the best assets of several different blocks in order to make it a viable candidate for many different types of motorsports. Consolidating several different part numbers into the Boss block hopefully will allow Ford to maintain costs and keep the Boss 351 block affordable for racers. Currently, the street price is less than $2,000, keeping it in line with other performance blocks.

"There were a number of different blocks that have come and gone over time," explains Mike Delahanty, Ford Racing's new Short Track Program Manager. "Some were optimized for short-track racing, while others were optimized for drag racing and other types of motorsports. And the idea with the Boss was to create one block that had the best properties of all of them.

"The improvements we've made are numerous," he says. "First of all, we're using a higher grade of iron that will provide better wear resistance, better ring seal, and better dimensional stability over the life of the engine. And from a design standpoint, this engine block was designed in the world of CAD. This really has the benefit of being designed from the ground up in the computer. That not only helped optimize things like the water jackets to make the cooling more efficient, but it also makes it a lot easier to check all the dimensions of a new block so that when a customer receives the block, it is dead on. So, there is less time involved on his end in blueprinting and bringing the block up to spec."