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02loftsmoor |
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#1
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Senior Member ![]() ![]() ![]() Group: Members Posts: 577 Joined: 26-June 11 From: Ft. Worth TX Member No.: 13,243 Region Association: Southwest Region ![]() ![]() |
I'm check on going with distributor-less ignition system, some pointers please
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Mark Henry |
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#2
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that's what I do! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada ![]() |
I don't know why you would bother doing this unless you are going FI (IMG:style_emoticons/default/confused24.gif)
Spend the money in the engine not on it. Only exception to this is headers which is the cheapest HP gain you can add to the engine. This mod adds zero HP. |
02loftsmoor |
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#3
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Senior Member ![]() ![]() ![]() Group: Members Posts: 577 Joined: 26-June 11 From: Ft. Worth TX Member No.: 13,243 Region Association: Southwest Region ![]() ![]() |
I don't know why you would bother doing this unless you are going FI (IMG:style_emoticons/default/confused24.gif) Spend the money in the engine not on it. Only exception to this is headers which is the cheapest HP gain you can add to the engine. This mod adds zero HP. OK I thought with more of a tune-able ignition you could squeeze a bit more out with out a lot of problems . you have forgotten more than I know,,, so I will ask and I do listen , and thank you |
Mark Henry |
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#4
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that's what I do! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada ![]() |
I don't know why you would bother doing this unless you are going FI (IMG:style_emoticons/default/confused24.gif) Spend the money in the engine not on it. Only exception to this is headers which is the cheapest HP gain you can add to the engine. This mod adds zero HP. OK I thought with more of a tune-able ignition you could squeeze a bit more out with out a lot of problems . you have forgotten more than I know,,, so I will ask and I do listen , and thank you Mark: Theory is that accurately timed/mapped spark is the only way to make power in an engine. Of course in practice, to do it correctly entails dyno time. When you change internals, the ignition map needs to change to take full advantage of it. Changes in compression, combustion chamber, valve size, cam profile, bore, plug location etc. all effect the flame front and timing for optimal ignition. You can twist an 009 to not ping at full advance, probably make good power at WOT and full advance, but everything in between that and idle is likely sub-optimal. Fueling is pretty lenient across AFR in terms of power output. I suspect that Jake has spent considerable time looking at ignition hook curves and the output of knock sensors while deriving ignition maps for his engines. But of course, some of us like to tinker with these things ourselves! WLD: Very cool. I have a pair of old T4 heads I considered using to jig up in the machining center. Pretty low priority project though, and seems like nerve wracking work if done to good heads. Ok, timing is important, you need a good curve, but to what point? Do you really need it? Many factors... like what are you running? Unless you are really high performance, programmable ignition is at best questionable. As far as a good curve a mallory will do that. Turbo yes it's good idea because it needs retard at boost. FI is also a good thing in this case. Twin plug, yes as it solves the second set of plugs. But performance NA, even high compression all you need 95% of the time is a good curve and a hot spark, a dizzy with MSD will do that. "But Crank fire is more accurate" OK...but how much and does it matter? Sure a dizzy gear has slop, but that only comes into play during deceleration and really that doesn't mean a hill of beans. Even crank fire is not really accurate often wandering 2-3 degrees at any given time at higher RPMs. Jarred's post is typical of what I often see making ignition (many systems) way more complicated than is needed. Maybe it's important on a F1 car...but a street car??? My SDS has programmable crankfire , really when you see the parameters on SDS you realize ignition isn't rocket science. As far as A/F ratio, jetting or your fuel map is the most important aspect. I've had and have just as good running engines with a good old dizzy. Not saying ignition (and curve) is not important, just saying at the state of tune of most street engines it makes little or no difference. |
stugray |
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#5
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None ![]() |
Ok, timing is important, you need a good curve, but to what point? Do you really need it? Many factors... like what are you running? Unless you are really high performance, programmable ignition is at best questionable. As far as a good curve a mallory will do that. If you tune on newer cars you will find that the high performance engines are pushing the car right to the edge of detonation (literally and figuratively). The knock sensors detect knock and vary the timing maps based on engine load, RPM, and knowledge of previous knock events. This allows them to push the timing advance to the absolute limit of knocking. I just jumped in because I understand the systems on the FA20 engine, and I have been tinkering with some "megasquirt-like" designs of my own. |
Mark Henry |
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#6
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that's what I do! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada ![]() |
Ok, timing is important, you need a good curve, but to what point? Do you really need it? Many factors... like what are you running? Unless you are really high performance, programmable ignition is at best questionable. As far as a good curve a mallory will do that. If you tune on newer cars you will find that the high performance engines are pushing the car right to the edge of detonation (literally and figuratively). The knock sensors detect knock and vary the timing maps based on engine load, RPM, and knowledge of previous knock events. This allows them to push the timing advance to the absolute limit of knocking. I just jumped in because I understand the systems on the FA20 engine, and I have been tinkering with some "megasquirt-like" designs of my own. Knock sensors will not work well on an aircooled engines as they are too noisy. "Newer" cars are watercooled and thus can tolerate leaner AFR's. Aircooled engines actually use the fuel charge to aid cooling. Leaning out an Aircooled you will immediately see your head temps go through the roof, the results will be bad. I suggest you have a very good head temp gauge. If you think you are charting new territory you are mistaken. Jake and many others have already experimented with this many years ago. But by all means carry on. |
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