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MSD Ignition LS1 LS6 Timing & Rev Control - Build An Ignition Curve

We show you how easy it is to convert a Gen III engine to a carb with the MSD LS6 Ignition-Control Box.

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'The new darling of the engine-swap set is the GM Gen III family of small-blocks that includes everything from the lowly 5.3L truck engine to the LQ9 6.0L all the way up to the swarthy Corvette LS7 427. But not everyone demands EFI sizzle with his Gen III steak. Capitalizing on that concept is the amazingly simple MSD Ignition conversion box that allows you to stick a carburetor on an LS1 or LS2 while still employing the very accurate GM distributorless ignition system (DIS). We've rubbed our greasy paws over this system several times, and it is so incredibly easy to use that there's no excuse for even considering adding a cumbersome distributor to the Gen III/IV engines. You don't even need a laptop computer if you don't want to get into that. If you can fog a mirror, you can plug in one of these boxes and supply accurate spark to any Gen III/IV engine. We'll run it down, and you can decide if it's cool.

The Background On DIS
Any good race-engine builder will tell you that a distributor is not the best way to accurately assign spark timing to a multicylinder engine. A computer triggering a coil per cylinder is far more accurate, which is what GM did with its Gen III-and-later engines. This type of electronic spark requires a few additional sensors, including a crank sensor to tell the box when the No. 1 cylinder has arrived at top dead center (TDC) and a cam sensor that tells the box when the No. 1 cylinder is on its firing stroke (remember that a piston on a four-cycle engine passes through TDC twice).

For those car crafters who would rather run a carburetor on a Gen III/IV engine, MSD created the original LS1/LS6 timing control box. Later, when GM upgraded the Gen IV engines by converting its original 24x crank-trigger wheel to a 58x, it required a new box, which MSD calls the 6LS-2 controller. Both of these boxes do essentially the same thing, creating finite control over the spark advance, vacuum or boost retard, multiple rev limiters, and even custom advance curve, all with a few minor keystrokes. Or, for those who have never overcome their fear of computers, the MSD boxes also come with six different plug-in chips, each with its own basic timing curve. On this level, the MSD conversion box is plug 'n' play at its finest.

The Hookup
OK, if this works so slick, it must take a computer science major to hook it up, right? Well, if a mere eight connections scare you (10 if you want the two-step and nitrous-retard features), perhaps that might be true. But this is really easy. Five of the connections consist of GM-style Weatherpak connectors with two that plug into each of the two coil packs, a three-pin connector to the cam sensor, another three-pin to the crank sensor, and the last Weatherpak connection to a manifold absolute pressure (MAP) sensor. Each connector is designed to plug into only its intended sensor so that they're goof-proof. The last three wires consist of a ground, a switched 12-volt power lead, and a tach lead. Hook those up, and the installation is complete except for mounting the box. Then just plug a basic timing-curve module into the side of the box and you are done. The only way this will get any easier is if somebody does it for you.

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1 comments
The Don-#002
The Don-#002

great, how about a article on working a 6al2 programable with a hall effect with the allowance for boost retard.also with various msd coils available, not std ones as shown here that were hooked into

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