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I can't tell you how long I agonized over publishing this ebook. I knew it would make for a great book, but what about the backlash? Would the big sanctioning bodies like NASCAR and NHRA, have my head? They would not be happy, I knew that. How could I say no? I couldn't.

Read on and find out more about this book...

Don Terrill (publisher at

"Hidden Head Porting -The acid alternative"

Author: Don Terrill Publisher:

What this ebook will teach you:

What NOT to do

  • The big mistakes acid porters are making.
  • Three reasons why the current method of acid porting is a bad idea.

What tools you need

  • A complete list of every tool you need.
  • Do I need to spend big bucks on tools? No.
  • What $5 tool will give you the biggest bang for the buck.
  • Where to find or borrow these tools.

How to make your own custom tools

  • How to modify tools to help in the cover-up process.
  • Your welding supply store might look at you funny when you ask for one of these items.
  • Simple steps for making the right tool.
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How to improve the airflow

  • Step by step instructions on how to modify the ports.
  • What areas of the port will give the most CFM per metal removed?
  • Three ways of modifying the combustion chambers for more flow.
  • Do these methods work on all heads? Yes, even aluminum.
  • How to improve airflow and still have the heads look stock.

How to cover up your work

  • The three must-do steps to hiding your work.
  • How to conceal your work at every step.
  • Color and texture are the two most important things in cover up. How to handle them both.

How to get through tech inspection

  • The two tips that will help get you through tech inspection.
  • How to know what you can get away with.
  • What do tech inspectors look for?
  • How to check your heads before you ever go to the races.

Customer Comments:

"Definitely a thumbs up! I can easily see how it would help improve flow without detection. Definitely shows some good trickery!"
Ken Kelly

"Great information, I can't wait to get started on a set of heads."
David Peisner

"Enjoyed your book."
Terry Parchem

"I won't let your secrets out of the bag."
Charlie Evans

"Loved the head porting secrets"
Bunner Engine Development

"I have just downloaded your "The Art Of Cheating" and "Hidden Head Porting" and LOVE them!"
Kent Strickland

What makes the author qualified to write this?

  • Dozens of National Records.
  • Has had winning engines torn down for inspection in both NHRA and NASCAR.
  • Has never been caught cheating.

Great Idea! Start your own business

Use this information to start your own hidden head porting business--you'll make over 20 times the cost of the ebook on your first job.

Frequently asked questions:

Question: I wound like to try it but it sounds tricky, I would hate to screw up a set of heads. Is it as easy as the web page makes it sound?

Answer: Yes, very easy--anyone can do it. This is a very safe and simple method of improving your heads when you race under a NO PORTING rule. There are multiple levels to this method--you can do as little, or as much as makes you comfortable.

Question: Isn't acid dangerous?

Answer: Yes very, that's why my information is devoted to a method that doesn't use acid. The method I show you will produce better flow numbers than acid, is a lot safer, and if done properly will be undetectable.

Special Bonus - Free unlimited tech support

Something you don't understand? Need some advice specific to your heads? No problem, I'll answer any and all questions.