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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. |
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Lo-Fi Version | Time is now: 28th June 2024 - 02:47 PM |
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