| My updates have been long
overdue. But now I'm trying to gather my thoughts here as best can. An essential part of my EFI project is the direct spark ignition. That means there's an individual coil for each plug. There are many options. I could have purchased one of those aftermarket coil packs. They usually require a separate "igniter" module between the ECU and coil. Instead, I chose the GM LS2 coils, featuring an integral igniter, so the ECU wires directly into each coil. These coils are available used at an affordable price. I got my pack from eBay. There are at least five generations of LS-family coils. One of the hottest is the "fourth-gen" LS2/7 coil, GM # 12573190, Delco # D514A, as found in 2005-06 5.3L, 6.0L and 7.0L Chevy and GMC trucks and Chevy, Buick, Cad, Pontiac cars. Another hot one is the "truck" coil GM # 19005218, Delco # D585, as found in 2001-2006 Escalade, Yukon, Trailblazer. |
 At first I tried to figure out how to use the factory sheetmetal LS2 brackets. But soon I designed a custom bracket, and had it laser-cut out of aluminum. There's only so much space here, but it works. The plug wires are 26-ohm MSD Super Conductor p/n 32819. You want to keep the plug wires as short as possible to avoid electromagnetic interference (EMI) that might hamper the ECU. Also visible here is the Bosch coolant temp sensor that I mounted on the thermostat housing. The ECU needs the coolant temp to determine warm-up enrichment. In addition, I'm using the information to turn on the electric fan. I have a 160ºF thermostat, and the fan turns on at 190ºF |
 In the sequential injection mode, the ECU needs a sync pulse from the camshaft, in order to know the engine position in the 720-degree (= 2 revolutions) cycle. The crank trigger tells the crank angle, but the ECU needs to know if it's cylinder 1 or 8 that is in turn. The signal doesn't have to come from the camshaft, but from something that rotates 1/2 crankshaft speed. In this case, I converted the original distributor to give the sync pulse. The ViPec V88 ECU only reads it once upon start, and then relies on the crank trigger only, as long as the engine runs. I adopted a trigger wheel from a Mercruiser boat engine (because I had one extra), and cut off all but one tab. The Hall sensor comes from an Opel distributor, thanks to my friend Jouni who's fanatic with Opels. Both the vacuum and centrifugal advance systems needed to be locked out. As for spark plugs, I'm using Champion RJ18YC for now. The plug needs to have 14 mm threads with a washer, 9.5 mm reach, and 13/16 hex. Similar plugs have been used in Buick Nailheads, Olds 455, Mopar 440, and many more. I've looked for other plug makes. NGK XR5 might be worth trying? |
To be continued... |
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