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Yes, that's the interesting thing. It was used in aircraft engines, so the idea is 50-plus years old. Maybe it was challenging in automotive applications where you have a lot of changes in throttle position. Farm tractor engines could have used it (steady RPMs).
Brian
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Quote:
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Hmm, some of the pistons used actually have a bowl in the top, opposite of a bump, like a diesel piston. Presumably this captures the mixture around the plug for more efficient combustion during lean-burn. Cool!
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I know, I saw that in the description. I'm just theorizing why direct injection might not have been best suited for automotive applications at the time (expense, reliability, etc.).
Brian
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How soon can weld up our intake ports and install DFI injectors to update our older engines?
![]() Brian
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If I understand it correctly, the direction injection used by M-Benz(50s) & D-Benz(40s) were injected into the cylinder rather than into the combustion chamber. These were MFI applications. This would make me assume that the advances have been made with respect to the injectors themselves rather than electronics.
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As you may know, the latest issue (April 09) of Excellence mag has revealed that the rod length of all four 9A1 engines (2.9-, 3.4-, 3.6-, and 3.8-litre) is 140mm.
All 9A1 engine versions except 3.6, share the same stroke of 77.5mm so the rod to stroke ratio is 1.8:1, which is very good, even better ratio than all versions of 3.6 GT3. Does anyone here know what is the rod length of the new 3.8-litre GT3 launched last week? I'd really like to know. I hope it's been lengthened from 131.5mm to something like 137.5mm for same ratio. ![]() Last edited by blue72s; 02-17-2009 at 08:14 AM.. |
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![]() ![]() Any new info out there? ![]() |
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120 HP/Liter is all I ask
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The wet sump system unbolts from the bottom of the engine as one piece, including the chain driven oil pump.
It looks like it would be easy to replace the sump and oil pump to convert to a true dry sump. The closed cylinder deck could receive press in Nikasil cylinder inserts. I wonder if this is in the cars for some variants for racing? |
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