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904svo |
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#1
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904SVO ![]() ![]() ![]() Group: Members Posts: 1,119 Joined: 17-November 05 From: Woodstock,Georgia Member No.: 5,146 ![]() |
While trying to make the jigs to drill my heads for twin plugs I ran into a
major problem. Where is the plug going to be located on the bottom of the head. I made up this jig to located where the plug will be located. Angle jig ![]() Test jig installed ![]() Installed ![]() Bottom view ![]() |
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Jake Raby |
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#2
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Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
Having done my first twin plug TIV engine in 1999 I have learned there are HUGE capabilities to be unlocked with the addition of a second plug in the chamber.
The second plug starts another flame front and the two meet in the center of the chamber, reducing overall timing necessary and increasing efficiency greatly. BUT when this is done all standard engine combinations and compression ratios are thrown out the window, else the result will be an untunable engine that makes no more power than a single plug. The key is cylinder pressure and a large bore. The large bore LOVES the second flame front. I do not twin plug a TIV engine with a bore smaller than 102mm because the gains have proven to be nil due to bore size. To date the most power we have made on PUMP gas with a 2.9 liter engine is 274HP at 6,400 RPM with twin plugs. Combinations as small as 2393cc (with a 105.07mm bore) have made as much as 265 HP. The 2.9 liter engine in my Wife's beetle back in 2007 made 249 HP with twin plugs and put down 200 of that to the rear wheels on pump gas while attaining 35 MPG figures on the highway. It took more than five solid years for Len and I to figure out the best way to outfit the heads and just recently have I complete the ignition system that allows twi plugs to be applied easily. Its a never ending evolutionary process... |
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Lo-Fi Version | Time is now: 25th June 2024 - 05:44 PM |
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