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les_garten les_garten is offline
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Join Date: Jun 2003
Location: PSL, FL
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Originally Posted by 911nut View Post
Twin plugging is use on high compression N/A 911 engines because the piston dome cuts off half of the chamber, which retards the velocity of the flame front. The unburnt mixture on the other side of the dome then combusts in a uncontrolled manner which results in the pinging that can sometimes be heard.
As 125shifter stated, it stands to reason that the flat top pistons used in turbo motors have the same issues.
It's interesting that Porsche didn't use twin plugs on the 3.6 turbo engine. Could it be they didn't feel that the added complexity and expense were worth limited benefits?
Porsche is a small Auto company. It costs a lot to change a lot of things each year. The main thing is that Porsche has been using Twin Plugz for a long time in their racing cars, and are using it in their production cars.

Gentleman, this is no Humbug!!
---Les Garten---85 930, Andial IC, GHL Headers, Fabspeed Dual, K-27 HF2, 3.4 JE Full Finned 7.5:1 CR, 964 CAM'd, Carerra 3.2 Manifold Cut/Flipped, Tec3r, Siemans 55#, GSF Fuel Rails, Clewett Crank Trigger, Clewett Cam Trigger,Dual Plugged, ARP Head Studs/Rod Bolts, Clewett Wires.Tial 46mm WG, Tial 50mm BOV, WEVO Shifter,934 Boost Gauge, Wideband EGO Sensor/Gauge, C2T Head Gaskets, '88 MB 300TE,BMW R100RT
Old 03-04-2008, 09:22 PM
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