Comments by "mpetersen6" (@mpetersen6) on "What's The Best Engine Configuration?" video.

@vincentlopez1350 Depending on where you are you have interesting options. Australia, JDM inline or the Barra. Europe, BMW or Jag (1). North America, just about any inline. People have been cutting and welding together V-8 heads to put on top of inline sixes for a long time. Chevy OHV I6 and Small Block have the same bore centers. The AMC/Jeep matches the Ford small blocks and is only .020”/.5mm less than the SBC/LS. Then there is the GM Atlas. Calvin on Nivlac57 has been getting obscene power out of them.
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@EbenBransome The harmonic range is usually somewhere in the 6k rpm range iirc. But inline sides will spin higher. People have even spun the Jeep 4.0 to 9k. And that's with the inefficient now non crossflow head. In Argentina they use a modified 4.0 with a twin cam 24v head for race purposes. Along with Chevy and Ford I6s.
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@EbenBransome A lighter crank can allow faster rpm increase. After all it takes energy to spin the mass up. And the 4.0s getting spun up to 9k. That was on a 6 cylinder dragster with a thoroughly modified 4.0. Definitely not the stock drive train. Or extended time periods.
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