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McMark |
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914 Freak! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None ![]() |
This question comes up every once in awhile, and did again in another thread. Rather than replying there I figured I'd make a new thread.
The 2270 number comes from 96mm pistons and 78.4 as the stroke. I'm pretty sure this 78.4 BS came from building motors for a racing class (probably under 2.3l) where people were trying to get as close to the limit as possible (more power). But the reality is that most 2270 engines are actually just off-the-shelf 78 stroke cranks. So 2258 is a better general reference term, I'd say it's more representative of what the engine is. But it doesn't roll off the tongue. I've moved to simply referring to them as 2.3l engines. If you REALLY want to be accurate, the '2270' that I'm assembling right now had a crank 78.26 and a 96mm bore. So really it's a 2266... (IMG:style_emoticons/default/rolleyes.gif) So call it a 2270, a 2258, or a 2.3l -- they're all the same idea and none are really all that accurate. |
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Mueller |
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914 Freak! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 17,146 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None ![]() ![]() |
Is that long stroke + smaller bore more favorable and longer lasting than a short stroke + large bore motor? (street and hooning around)
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McMark |
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914 Freak! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None ![]() |
Is that long stroke + smaller bore more favorable and longer lasting than a short stroke + large bore motor? (street and hooning around) I think you're asking why none of these engine combos use pistons larger than 96mm. The answer is cylinder to head sealing. At 96mm things aren't pushed very far beyond stock and are therefore more reliable. If you go all the way to 103mm the cyl-to-head seal is very thin. The only real way to make a 103 work long term is to work with LN Engineering Nickies to retain a suitable sealing surface. They can make a single set with any design, whereas steel cylinders are only being reproduced in that shape. |
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