Ford's cast-iron racing heads,...
Ford's cast-iron racing heads, the N351 and N352 models, feature raised ports with good flow. The exhaust port is especially improved over previous versions, which means you don't need much more than a few degrees of extra duration on the exhaust lobes on your cam.
Go with the Good Stuff It used to be that when you went to build an engine for your race car, you didn't have much choice except to start with an old production street block. Our demands for a good race block have advanced to the point that it's just no longer reasonable. Ford Racing and other manufacturers have produced blocks specifically for racing that give us a lot more of what we need in a race engine. Put it all together, and a junkyard block may sound cheap in the beginning, but it is really more money after you put in all the time and effort to bring it up to spec. Ford and some of the other manufacturers have done a really good job of bringing what's normally called a Sportsman block to the plate. It isn't as expensive as a Nextel Cup block, but it offers a lot of the same advantages.
Besides Ford, Dart also makes a good Sportsman block. To begin with, Dart's block can be built as either a wet- or dry-sump engine. These blocks are also cast from better material, and core shift is minimized. On the Dart block, I know that the oil galleries have also been revised. In a dry-sump application, you can oil the thing from the front, the rear, or both. When you oil from both the front and the rear, you can actually cut your oil pressure back tremendously. That's obviously an advantage in terms of power because when you run less oil pressure and still keep proper lubrication, it saves you horsepower.
No matter what Ford block we use, we still spend a good bit of time with each one to lighten it up. If a person is weight conscious, you can lighten just about any block. Some areas from which we get the most weight are the bellhousing area of the block and, if you are running a dry-sump, the filter boss. Internally, in the area where the oil pump would normally go, we remove all that material. There are many other areas where you can trim down and thin out a little. We can get 15 pounds off of one of those blocks without getting close to water or oil galleries-it's not too much trouble at all.Joe RhyneRhyne Competition Engines219/845-1218
It may be tempting to try...
It may be tempting to try to save a little money up front, but Ford's Sportsman block, and other racing blocks produced by other manufacturers, is better quality and actually saves you money when you calculate the additional processes it takes to bring an OEM block up to par.
Go Easy on the Gears
Be careful with high-volume oil pumps if you're running a wet-sump engine. A high-volume oil pump requires more power to turn, and that can put a real load on your distributor gear. You can wipe out a Ford distributor gear quite easily if you aren't careful or if the cam gear and the distributor gear don't mesh properly. If you determine that you need to run a high-volume oil pump, there are a couple of outfits out there that offer quality high-volume oil pumps for racing. Those companies have done some work to the Ford geroter pump and significantly reduced the amount of horsepower it takes to turn one, which will help the life span of the distributor gear.Jeff KlaverFord Racing586/468-1356www.fordracing.com/performanceparts
Know Your Flow
Your camshaft doesn't care what label is on the valve covers. It really doesn't perceive whether it's going in a Ford or a Chevy, but what it does perceive are things like port size and shape and valve size. It's hard to make global generalizations when it comes to building Ford engines because there are so many options available, but we can do some things with specific cylinder heads.
If you are racing cast-iron heads, Ford's N series of heads (N351 and N352) are pretty good pieces. They have raised exhaust ports that flow well, and the camshaft durations between the intake and exhaust should be relatively close.