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FORDMUSCLE.com
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by Jim Langley

Introduction
The aftermarket today for the Ford Windsor small block is absolutely fantastic. No more does the Chevrolet crowd have the monopoly on easy to find go-fast goodies. The advent of the fuel injected, roller-cammed 5.0 V8 changed all that. True, the prices are still slightly higher for the blue oval parts but nowhere as high as they used to be, and the availability is now basically equal. Take the aftermarket cylinder head arena, for example. It is absolutely overrun with choices- aluminum, iron, ported, and even some decent stock offerings. With prices ranging from about $650 to well over $1500 for a good set of bolt-on heads many of us can't swing that without seriously compromising our credit ratings and good standing with our significant other. We here at Fordmuscle have lived through that and tried a cheaper alternative- porting stockers ourselves. The results were pleasantly surprising. A set of '69 351 Windsor heads actually flowed as well as box stock Edelbrock aluminum castings once larger valves were installed. Even more impressive, was that this was only the second set of heads this author had ever ported. With such encouraging results we felt we should pass on what we learned so those with plenty of time and little cash can duplicate our efforts.

Why port stock heads?
The answer is plain and simple, stock small block Ford heads SUCK! Actually they wheeze... like trying to breath through a swizzle stick. From the factory, almost all of the heads offered up to 1995 couldn't flow enough air to get much more than 250hp out of a 302. Two noticeable exceptions are the GT40's on the EFI 5.0 Cobra's and the recently released GT40P's found in 5.0 Explorers. The Boss 302's worked well as long as you stayed above 5000rpm (besides, they were Cleveland heads anyway.)

Since the stock heads flow so poorly it is just about impossible to screw them up... but it is possible. That's why we put together this article. By understanding the fundamentals of porting, you can pick up that die grinder or Dremel tool with confidence, and come out with a set of heads that will rival the brand name castings. By the way, if you already spent money on aftermarket heads, or if you own an FE, Cleveland, or and other Ford engine for that matter, you should still study this article -while some of the details may be Windsor specific, the principles apply to really any cylinder head out there.

A simple cartridge roll clean up and smoothing of the ports, runners, and bowls plus clearing out the smog injector bumps (if present) can net you around 20 horsepower. Throw in some basic gasket matching, valve guide boss work, combustion chamber shaping, large valves, and you can see well over twice that. Gains like this are definitely worth it if you can spare the time but not the cash. Don't worry if some of these terms are new to you, we'll define them for clarity before going off the deep end.


Tools


A quality carbide cutting bit is indispensable when it comes to porting iron heads. They are not cheap, so get an assortment if you plan on porting as a side job, other wise one or two bits will suffice. The bits shown here are available through Mondello.

The best tools for head porting are either an air operated die grinder or high-speed electric grinder (Joe Mondello prefers Makita electric.) Of course both of these can be expensive. This author has used a 12 volt cordless drill for the carbide work and then a Dremel tool with a flex-shaft for reaching into the intakes. The high speed grinders are quite a bit faster.

There are nice porting kits available today that come with a variety of cartridge rolls and grinding stones in varying grits. Most do not include a carbide bit, which is just about mandatory if you are working on exhaust ports with smog bumps. The Eastwood Company and Standard Abrasives does have them at extra cost. Joe Mondello will soon be offering a complete line of kits including carbide bits made to his specifications. They have longer shanks (shafts) and special shapes for specific porting requirements. Look to spend between $30 to $50 for a good, quality carbide bit. A good shape for all around use is a conical or football bit.

Working with a fifty-pound chunk of iron is not easy. You dont want to be porting while trying to balance the head on a flimsy work surface. Find yourself a sturdy work bench, or fab one up with saw horses and 2x4's. The head itself should be level, stable, and angled such that you can look directly down the ports as you grind. A few pieces of 2x4 can make for a very functional head stand.

Getting Started
Before starting, find a shop or friend that has aftermarket heads, preferably in aluminum. Inspect the ports both visually and with your fingers. Your sense of touch will be very useful for checking your progress. I fondled a set of Edelbrock heads about a dozen times before I started porting. Finally, I bought a dial caliper so I could check my progress and try to keep the port sizes equal.

Before you begin, decide if you are going to put in new valve guides and have new valve seats cut. If you are going with new pieces you don't have to be as careful with the bits skipping, otherwise, a gentle touch will prevent damage to them. In general it is good practice to plan on having a valve job performed after you are done porting.

Finally, before taking your carbide bits to the ports, get a feel for how they cut. Try your different bits on the casting ridges on the ends of your heads,or on a spare junk head. Your local machine shop probably has a junk head they are willing to give you. You can even start working on grinding down the Thermactor bumps in the exhaust ports. Keep the grinder moving up and down, and in a circular motion. Don't let it stay in one spot for any length of time. By constantly moving the cutting bit and applying gentle pressure you can cut nice, straight walls.
Remember, let the tool and it do the work, a lot of pressure is not neccesary and only leads to quick wear of the bits and grinder.

How Far Can you Go?
Stock small block Ford heads have pretty thick walls, and there are really no critical thin areas. Nevertheless it is indeed possible to make a wall too thin, or actually cut into a water jacket. Professional porters work against these limits all the time, but, for the home porter, if you stay within the guidelines offered in this article, you won't be anywhere close to damaging the head. An experiened porter will also tell you that you can "hear" when you are cutting close to a thin area -as the tone of the carbide cutter will change to a higher pitch. Continue


(How to Port)

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In This Article:
FordMuscle shows how to gain horsepower on the cheap by porting your stock small-block Ford cylinder heads.

 

One positive attribute of the Ford heads is the architecture. The ports are evenly spaced on both the exhaust and intake sides of the heads. Chevrolet stock heads have siamese ports on both sides. This means that the port size and shape are the same port-to-port on the Ford heads. This is critical on high performance motors. The Chevy ports have nice internal shapes but are different lengths! Why do you think the NASCAR guys pushed for development of the SB2 head for Winston Cup racing? They couldn't compete with the Yates and Roush motors consistently. The new Chevy Head has adopted the even port spacing of the Fords.
 

Makita GEO600 Electric Die Grinder The ultimate in grinding!

Dremel tool with flex shaft attachment. Not powerful enough for cutting iron, but great for smoothing, polishing, and working in small areas.


Sanding rolls, like these from Standard Abrasives, are needed for smoothing and polishing.

 

 


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