Quote:
Originally Posted by Ecky
I'm not too terribly informed about cam profiles, but lower lift AND duration should (to a point) move peak torque lower in the RPM band, where almost everyone on this site drives, right?
Also, I'm willing to bet there isn't a better cam that could be made for my car. It seems Honda gave their engineers leave to go all-out for the first-gen Insight.
EDIT: Welcome to the forum!
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Fixed it for ya...
The reason they almost always use lower LIFT with lower DURATION is due to Ramp Rates. High Ramp Rates equate to more lift with less duration, but more stress on the valvetrain components (guides, stems, rockers, lobes...)
The beauty of this here ECO-Modding Movement is that we can use some of these higher-stress arrangements to our advantage, because we run lower RPMs nearly all of the time!
As for your Honda Engineers, I'm willing to bet they were so "handcuffed" by EPA and cost constraints they felt fortunate to get the 50+ rating they got... I used to belong to an automotive engineering bbs in the engine forums, and the consensus amongst the engineers there was that the emissions BS was the biggest enemy to economy, and hence, created more pollution. Which is normally dealt with by catalytic converters.
I also read a statement by an auto-engineer that said they dump late-cycle fuel in just before the exhaust valve opens to, (and I quote) "Keep the cats up to optimum operating temperatures". End Quote. Meaning:
They waste fuel to keep the cats warm "just in case" they cool off and you get a happy right foot!
Thanks for the Welcome, Ecky!!!
Hope to see you around!