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fredmeister fredmeister is offline
Smart quod bastardus
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Join Date: Oct 2002
Location: Baltimore, MD, USA
Posts: 2,232
Actually you guys have hit it on the head with the explanations given:
1) Twin Plugging makes you engine less prone to detonation
2) Makes your car less prone to Bad Gasoline related pinging
3) Given Identical Engines, you can retard the timing on the twin plugged engine relative to the non twin plugged engine to make the same power
Expanding on item 3 allows you to advance the timing further than single plugs allow thus to gain more power. You can also run higher boost levels with the single plug timing values to make more power without detonation.
I have read that the theoretical limit to diameter size in the aircooled Porsche cylinder is around 95or 96mm before you start having trouble with combustion ie detonation. Basically the flame front takes too long to travel across the entire cylinder diameter at this range. This explains why Porsche went dual plug on the 3.6 liter engines.
Twin plugging allows you to run more technology improved ignition systems and smaller plug gaps as well since you will need to replace the single plug distributor anyway. It is alot of expense, you need to weight that against the overall advantages mentioned here.
1979 930 Turbo....3.4L, 7.5to1 comp, SC cams, B&B intercooler, Snow Perf water/meth injection, Rarlyl8 headers, Garret GTX turbo, 36mm ported intakes, Innovate Auxbox/LM-1, custom Manually Adjustable wastegate housing (0.8-1.1bar),--running 0.7bar max
---"When you're racing it's life! Anything else either before or after, is just waiting"
Old 03-04-2008, 11:01 AM
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