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Chevy Resto Tech - July 2014

Mark Lundquist Jun 10, 2014
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Tip of the Month

As you may remember, in our March ’13 issue we installed an MSD Atomic EFI system on our ’65 Chevelle 502-powered project car. So far, the system has proven to be dead reliable with a few tweaks. Although the basic parameters can be programmed into the system, the complicated fuel and ignition maps cannot be accessed by a laptop computer, like some other systems on the market. The system was designed to be simple and reliable for the average car guy, without the hassle of complicated tuning.

For the most part, the system’s learning function does a good job. However, as with any sophisticated electronic system, including your home computer, updates to fix minor problems are available from MSD. Case in point would be the cold idle quality of the Atomic EFI. If I had to pick any fault of the system, it would have been the cold idle. It could have been better. What do you know? MSD addressed this issue with an update in September of last year.

Kingston 4gb Micro Sd Card Adapter 2/2

The update is accomplished by downloading the software to an SD card from your home computer. The MSD kit comes with an SD card and adapter that plugs into your PC, and then transferred to the handheld MSD unit on your system. Sounds complicated, but if I can do it, so can you. If you didn’t get the SD card and adapter, your local electronics store (or even Walmart) will probably have one for less than 10 bucks (see pic).

Once you have the SD card, simply go to for directions and software updates, and to register to receive updates by email. The updates can be put on your desktop, and as soon as you plug in your SD card to the PC, a window will appear. Simply click and drag the updates you received from MSD from the desktop to the SD card window, and it will automatically load the SD card. Take the card and plug it into the SD slot on the upper right corner of the handheld MSD programmer, and it will automatically update your system. This is a hard reboot, and it will wipe out all previous information, so you must write down any specific parameters you had programmed in. The website has a short video to walk you through the simple process. By the way, the latest update cured the cold idle issue on our Chevelle ZZ502/502. Isn’t technology grand?

Is It For Real?

I have exhausted several leads trying to discover if this Chevelle I inherited is exactly what I was told it is. It is (by title and factory buildsheet) a ’66 Chevelle SS badged a 396; however, the block number comes back as a 427/450. According to my uncle, the car is completely original, which is possible with only 48,970 original miles. He told me Chevrolet did badge several Chevelles with the 396, even if they had the 427 engines, but I can’t find any documentation to support this. Have you ever heard of this or do you know where I can find out the truth?

via email

Without the actual block casting number and the engine suffix code on the block pad, it’s hard to say what you have and why. The two-letter suffix code on the block pad might give you a clue as to the origin of the engine. The engine pad, however, is the easiest one of the numbers on a Chevy engine to restamp or change. There were only two cars Chevy manufactured in ’66, the Corvette and the fullsize passenger car, listed to get the 427. The Corvette suffix code would be one of the following: IM, IL, IQ, IR, IK, or IP. The passenger car would carry only ID. So if the pad on your Chevelle engine carries any of these suffix codes, it’s likely it was transplanted from either a Corvette or passenger car. Yes, I have heard of the 427 in a ’66 Chevelle, but at this time, to my knowledge Chevrolet hasn’t acknowledged any were built, or that any factory-installed 427s exist. None has ever been documented.

The general consensus dictates the engine was put in at the dealer level, and wasn’t a factory option. (There were a few dealers like Baldwin Chevrolet, with Motion Performance, in Long Island that did this.) Without an original buildsheet showing the 427 engine, it’s hard to claim it was a factory build. Even the ’66 Chevelles that appear at auctions are mostly labeled as re-creations or Corvette transplants, and not original. Having said that, I think if you could prove through documentation it was installed at a Chevrolet dealer in 1966, you would have a rarity and it could only enhance the value and bragging rights.

Got a restoration question that’s been puzzling you? Send it to:
[ m ] Super Chevy, Resto Tech, 9036 Brittany Way, Tampa, FL 33619. [ e ] [ f ] 813-675-3557



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