| The high performance aftermarket world I must say | | | | aftermarket manufacturers are producing parts that |
| has come a long way in producing some excellent | | | | are stronger and more reliable but the cylinder heads |
| parts that the average hot rodder has easy access to. | | | | they are producing is what makes the power. That's |
| A simple point and click from your home computer and | | | | not to say you can't take a stock set of heads and |
| you can have the latest in high performance parts | | | | make them better because that is a low cost option |
| delivered to your door in a matter of days. Most of | | | | that will likely give you the greatest gains per dollar |
| these fine parts you are able to bolt on with little or no | | | | spent and can also be fun and rewarding when done |
| modifications. | | | | yourself. Even some "as cast" aftermarket heads |
| But as I sit in my garage and look at the beautiful 523 | | | | have room for improvement with some port matching, |
| cubic inch engine I recently built for my drag boat I think | | | | smoothing of the ports, proper shaping of the guide |
| to myself what really has changed? It's pretty much | | | | boss and blending of the bowel area you will see |
| the same as every other engine I've built in my life, | | | | some power gains. |
| block, crank, rods, pistons, heads, valvetrain, intake | | | | If you have never done any porting work before I |
| system, etc. The basic concept of the internal | | | | suggest you find yourself a junk head to practice on |
| combustion engine remains the same. So my question | | | | first and get the feel of things and then move on to |
| to myself is what has changed? Today's high | | | | the heads you intend on using. |
| performance and racing engines produce much more | | | | Remember bigger is not always better when it comes |
| power than they did even ten years ago, so again, | | | | to cylinder heads. It's all about proper shape and |
| what has changed? The answer I came up with is | | | | velocity. |
| simple- air flow. Although the concept has never | | | | It's also important to know your intended use, street, |
| changed, the more air you can get into the cylinders | | | | street rod, drag race, rpm range, etc. so you can |
| the more power you will produce. What is the path the | | | | choose the right cylinder heads or modifications |
| air needs to take to make it to the cylinders to be | | | | needed for your application. Just having your heads |
| combusted? It travels and is distributed through the | | | | ported or choosing the heads with the biggest ports |
| cylinder heads. Cylinder head air flow is, and in my | | | | doesn't mean you'll make more or the most power |
| opinion, will always be the major factor in producing | | | | from your engine. Answering these questions first will |
| more power in the internal combustion engine whether | | | | help you determine optimum port size and air flow |
| it be through larger camshafts, bigger valves, larger | | | | requirements. It's also a good idea to call the |
| cubic inches, ( which seems to be the case | | | | manufacturer and get their recommendations. |
| nowadays) or bigger superchargers, it still comes | | | | There's plenty to choose from out there, choosing the |
| down to airflow. | | | | right parts is what's important. Good luck and have fun. |
| Like I stated in the beginning of this article the | | | | |