When I started CustomEFIS in 1999 I soon released a GM DIY EFI Manual. This manual had four major sections, an ignition section, a fuel delivery section, an electronics section, and the software calibration section. Due to changing technology and improved methods on my part, I stopped selling my DIY EFI Manual in 2005 so that I could write a new and improved version. I am now offering the new version for sale. To accomodate my new business strategy I re-wrote my manual as a software tuning guide only and moved all information regarding EFI hardware to my website. When re-writing my manual I wanted it to not only be the tuning guide for all future EFI systems, I wanted it to be a stand alone manual that I could sell independently to teach GM EFI tuning to anyone. This is also the manual that I include with my GM EFI tuning packages sold on this site.
The information contained in my DIY manual is the foundation of this business. You will not find this info in any mainstream book on Amazon.com or Barnes and Noble bookstores. How do I know? Because I've bought all the fuel injection books and none of them covers the software that runs the engine to any significant depth. Once you read my manual it should be crystal clear that you can use a GM ECM to run any fuel injection system (with a few exceptions that I cover on my website). It should also be clear that you don't have to build an engine to match a chip such as using a so-called computer cam. Build the engine to make the power you want out of it and then make the chip suit the engine. Making the chip match your engine is the intent of this manual.
To me the coolest thing about GM EFI is that you can install a GM EFI system, make some basic timing and idle speed hardware settings and then close the hood and complete the tuning process with a laptop in the car. I was reading a user manual for an MSD distributor the other day and it mentioned installing different springs and different stops for matching the timing to your engine. Testing different springs would require you to stop the engine and disassemble the distributor to make these changes. With GM EFI connected to a laptop inside the car you would just use some tuning software to change the settings on the screen and BAM you're done. The ability to make changes so easily allows you to fine tune both fuel and spark timing to the nth degree compared to opening the hood and changing physical settings in the distributor and carburetor. If you are a mechanic and want to move out of the dinosaur age then you must learn to re-calibrate EFI systems.
Of course if you don't know how to re-calibrate the ECM then this is also the most terrifying aspect of installing a GM EFI system. My goal in writing this manual was not only to guide you around the pitfalls of which parts not to use but also to explain how to re-calibrate the ECM to run just about any engine. You don't need to learn Ford, Chrysler, or any other system as a GM ECM can be adapted and re-calibrated to run any other engine. Of course if you already have a Ford, Chrysler, or foreign EFI vehicle then the concepts in this manual apply to those systems as well. I just don't go into the specifics of Ford, Chrysler, or foreign ECMs. I only cover GM in my manual.
If you are considering building and installing your own GM EFI system then this manual will be the most important purchase of the entire system. If you don't learn to re-calibrate the ECM, you should definitely keep using a carburtetor on your engine. I know of no other published book with the in-depth coverage of GM EFI than my manual. It is a compilation of tons of internet information as well as my experiences in running a GM EFI kit building business for the last 9 years. Also, if you purchased a system from my competitors such as Affordable EFI, Howell Engine Management, Turbo City, and others this manual will teach you how to tweak the calibration of their systems too. And I can almost guarantee that you will need to knowing what I know about running a GM EFI based business.
Finally, if you own a GM car or truck from 1985 and up, this manual will help you understand how it works. You will know enough to understand what the ECM does and whether it needs some tweaking. If you changed the engine from its stock configuration, it will definitely require tweaking the calibration.
My DIY GM EFI Tuning Guide is now available for $30 including shipping and handling in the USA. Non-USA purchases will require extra shipping. Email me for the cost. To purchase my manual send a check or US post office money order to:
Customefis
PO Box 804
Hamilton, GA 31811
To order a manual by credit card click on the Buy Now button below. Click on the button to order a DIY manual only. Other products are ordered elsewhere on this site.
If you found this manual on Ebay and want to purchase a copy, DO NOT click on the Ebay BUY IT NOW auction. Instead click on the BUY NOW button on this page and save $5. Ebay charges a final value fee on each copy sold so I have to pass that fee on to the customer. Again, DO NOT CLICK ON THE EBAY BUY IT NOW AUCTION IF YOU WANT TO SAVE $5.
Be sure to include your return mailing address with the payment or email me with that information.
Previous customers who purchased my first manual version are entitled to a free copy of this new manual. Email me with your name and address for a copy.
As I mentioned above, all hardware information regarding GM EFI systems was moved to a password protected section of my website. Once you have purchased my DIY GM EFI Tuning Guide email me for the password to the hardware information.