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Old 12-16-2015, 03:24 AM   #154
totopo
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Quote:
Originally Posted by CSG Mike View Post
Ram air is grey area.

Nitrous, while adding oxygen content, does not stop the engine from naturally sucking in the air itself.

Forced induction would imply that the pressure inside the manifold is above atmospheric, due to something forcing air into the engine, causing it to imbibe more air than it can on its own.

Since you're a drag racer, I can see why you would consider Nitrous FI; it's not "all motor". While excluded from "all motor", it's still not forcing a positive pressure into the manifold, the engine is still aspirating on its own.
If you say nitrous is na, then yes, a 300hp fa20 on nitrous would need beefy internals just as much as a 300hp fi motor because the cylinders are seeing the same pressures.

The reason that na doesn't need as strong internals as fi is because you are normally limited by the amount of air that you pull in. You can make it as efficient as you want and there is still a max bmep that you cannot surpass. but if you are saying nitrous counts, nitrous causes pretty insane cylinder pressures, so the end effect is the same as fi. You get hp with more air instead of more revs.

Edit: of course that is assuming you are using nitrous ALL THE TIME. The fact that it is just sporadic makes it like a scramble button on a fi. It would be like if you normally ran super low boost then periodically ran short stint at high boost. Is the failure rate acceptable with that usage? Who knows
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CSG Mike (12-16-2015), FRS Justin (12-16-2015)