We left off in Part One with a completed short block, already stabbed with a healthy Crane soid roller cam which will help reach our goal of 400 HPs. What remains of course is the top end. This is where the power is made, and thus proper component matching is critical. In this article we'll go through the head and intake selection and assembly.


World Windsor Sr. feature 200cc intake ports.
As we mentioned last month, we will be running the World Products Windsor Sr. heads. We choose these because we got them cheap (used), with relatively few have a few miles on them. In fact, they are under $800 new, and so long as you don't mind the weight of iron, they flow as good as most 'out of the box' aluminum heads. The heads will be a substantial improvment over stock castings, in that they have a redesigned combustion chamber, modified spark plug placement for better burn, and of couse the larger 2.02" intake and 1.60" exhaust valves to increase flow. The World Sr. comes with massive 200cc intake runners which, if ported, can support displacements much larger than 302 cid.

Head Clean Up and Prep
Small block Ford heads are have notoriously restrictive exhaust ports and bowls, and that is where most professional porters spend their efforts; especially on stock castings. Although the World heads would work great out of the box, we noticed quite a bit of casting flash that could easily be removed with a grinding stone. This sort of "clean up" work is cheap and easy horsepower.

There are many stages of porting heads, ranging from the basic clean up to the complete re-shaping of the ports. If you don't know what you are doing, taking off too much material in the wrong places can easily cost you power and even ruin the head. Therefore we suggest you leave a full-on port job to the pro's.
All we performed on the iron World Sr. heads was to smooth out some casting ridges and irregularities as shown below.

On our cast iron World Windsor Sr. heads there were sharp edges and casting material around the valve guide bosses. We used our sanding rolls to smooth this out and blend the area around the guides. This will reduce airflow turbulence.

Looking down the intake port of our our of the box World Sr. heads, you can clearly see the surface irregularities on the walls, and the large casting ridge running down the center of the floor. A little time and effort spent smoothing out these imperfections with a die grinder or Dremel tool can substantially improve flow and performance.
We had the heads milled to clean up the mating surface, but also to gain some compression. The 64cc head was milled down to 59.5cc, in order to yeild about 9.4:1 compression ratio. We then checked the combustion chamber volume. See Measuring Combustion Chamber Volume in the Fundamentals section of the Tech Department for a detailed tutorial on this process.

(Head Assembly)
In This Article:
We go through the steps and details required to achieve greater than one horsepower per cubic inch from our 302 motor. Part 1 details the parts selection and short block assembly. Part 2 deals with the top end assembly and leads in to the dyno results.
Part I Short Block
Part II Top End
Part III Installation
Part IV Dyno Testing
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