VAP
10-26-2004, 07:46 PM
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With the HallTech engine management going in over the next two weeks I started dabbling today with a way to convert my engine to direct fire sequential ignition with six coils instead of the stock setup's remote 3 coils with spark plug wires driving a "wasted spark" ignition method.
The big problem with wasted spark ignition is it fires twice per engine revolution, ie; once on compression stroke where combustion occurs and then the "wasted" spark on the exhaust stroke. The problem with this is coil dwell and energy buildup times are half what they could be if they only fired once. Compounded by the fact that there are only 3 coils and 6 cylinders. This means the buildup time for the coil to store energy to fire a spark plug is cut in half again.
With direct fire I eliminate all spark plug wires and the 3-coil bank that sits over the power steering pump and fires 6 plugs. I eliminate the possibility of spark plug wire leakages and shorts as well as never having to buy one (or 6) ever again. All I need do is add a second ignition module so that each coil has its own circuit then run a low voltage harness to each coil that will be almost identical in size to an injector wire harness. The results: far hotter and more precise spark with no wasted spark discharge weakening'reducing the subsequent spark (ad infinitum). Plenty of time for the coils to build a charge between discharges to the plug. Four times more time in fact, Makes for cooler coil temps, hotter spark, longer spark duration and longer coil life. The coils only working 1/4 as hard as on the stock system.
I was considering running my old coils from my UrS4 car but I'd need to buy an extra coil for the 6th cylinder. Those are older generation and probably 400% larger/heavier than these new generation coils. I never could've gotten the old ones to sit directly on the spark plugs as these do and I would've had to mount them remotely and run plug wires from each coil to it's respective spark plug. Defeats the purpose and not my style.
I stumbled on these at Champagne today and found they just snick right on to the plugs like they were made for 2.8 12V. Now all I need to do is buy 6 of these, add a second ignition module or 1 single one if thats how it comes from the factory on the new cars and make (or buy outright from the dealer) a wiring harness almost identical to the fuel injector harness and VOILA! Direct Fire Ignition!! Just like that!
But without stand-alone engine management you cant have it, or I should say you cant have it "all." You can have direct fire ignition. I started wondering how it could be adapted to a stock ECU 12V and while it cant be single spark it can "direct fire." It will still have the wasted spark on the exhaust stroke but each coil will only be firing one spark plug instead of two. That will allow 50% faster coil energy buildup and an accompanying hotter spark. This setup will also run cooler and could make as much as 50% hotter spark. It should increase coil life as each coil will only have to work 50% as hard as stock coils do now. It would also eliminate your existing coil packs and all spark plug wires. It would KILL such things as Nology wires for spark enhancement... I mean COMPLETELY BLOW THEM AWAY! But yes, all this hi-tech does come at a price... it will be expensive. Maybe as little as $350 but probably no more than $500 or so. But you can replace a coil for $40 (new) and you never buy ignition wires again or worry about a mis-fire associated with one or all of them. And you have better, hotter, more precise ignition spark than a set of $200+? Nology's or anything else in the same price range can ever give you. And everything fits neatly under the engine cover. No one will ever know unless you run "topless."
I'll put in more time over the next two weeks on this while doing mine and let everyone know how it unfolds and show you picturs of how mine turns out. My set-up with stand-alone engine management will be 100% identical to to the the stock ECU car. The difference is purely the ECU's used and not one item that fires a sparkplug will be different.
With the HallTech engine management going in over the next two weeks I started dabbling today with a way to convert my engine to direct fire sequential ignition with six coils instead of the stock setup's remote 3 coils with spark plug wires driving a "wasted spark" ignition method.
The big problem with wasted spark ignition is it fires twice per engine revolution, ie; once on compression stroke where combustion occurs and then the "wasted" spark on the exhaust stroke. The problem with this is coil dwell and energy buildup times are half what they could be if they only fired once. Compounded by the fact that there are only 3 coils and 6 cylinders. This means the buildup time for the coil to store energy to fire a spark plug is cut in half again.
With direct fire I eliminate all spark plug wires and the 3-coil bank that sits over the power steering pump and fires 6 plugs. I eliminate the possibility of spark plug wire leakages and shorts as well as never having to buy one (or 6) ever again. All I need do is add a second ignition module so that each coil has its own circuit then run a low voltage harness to each coil that will be almost identical in size to an injector wire harness. The results: far hotter and more precise spark with no wasted spark discharge weakening'reducing the subsequent spark (ad infinitum). Plenty of time for the coils to build a charge between discharges to the plug. Four times more time in fact, Makes for cooler coil temps, hotter spark, longer spark duration and longer coil life. The coils only working 1/4 as hard as on the stock system.
I was considering running my old coils from my UrS4 car but I'd need to buy an extra coil for the 6th cylinder. Those are older generation and probably 400% larger/heavier than these new generation coils. I never could've gotten the old ones to sit directly on the spark plugs as these do and I would've had to mount them remotely and run plug wires from each coil to it's respective spark plug. Defeats the purpose and not my style.
I stumbled on these at Champagne today and found they just snick right on to the plugs like they were made for 2.8 12V. Now all I need to do is buy 6 of these, add a second ignition module or 1 single one if thats how it comes from the factory on the new cars and make (or buy outright from the dealer) a wiring harness almost identical to the fuel injector harness and VOILA! Direct Fire Ignition!! Just like that!
But without stand-alone engine management you cant have it, or I should say you cant have it "all." You can have direct fire ignition. I started wondering how it could be adapted to a stock ECU 12V and while it cant be single spark it can "direct fire." It will still have the wasted spark on the exhaust stroke but each coil will only be firing one spark plug instead of two. That will allow 50% faster coil energy buildup and an accompanying hotter spark. This setup will also run cooler and could make as much as 50% hotter spark. It should increase coil life as each coil will only have to work 50% as hard as stock coils do now. It would also eliminate your existing coil packs and all spark plug wires. It would KILL such things as Nology wires for spark enhancement... I mean COMPLETELY BLOW THEM AWAY! But yes, all this hi-tech does come at a price... it will be expensive. Maybe as little as $350 but probably no more than $500 or so. But you can replace a coil for $40 (new) and you never buy ignition wires again or worry about a mis-fire associated with one or all of them. And you have better, hotter, more precise ignition spark than a set of $200+? Nology's or anything else in the same price range can ever give you. And everything fits neatly under the engine cover. No one will ever know unless you run "topless."
I'll put in more time over the next two weeks on this while doing mine and let everyone know how it unfolds and show you picturs of how mine turns out. My set-up with stand-alone engine management will be 100% identical to to the the stock ECU car. The difference is purely the ECU's used and not one item that fires a sparkplug will be different.