Quote:
Originally Posted by supremeefi
If they're isolated then they don't share the others dirty air at the wrong time.
I've done a few where they had tunnel rams or other common plenum intakes first. Idle rpm's ranged from 1100-1400 rpm's and were rough no matter what. Once they got a properly tuned true isolated IR intake all of them idled at 800 and where as smooth as silk. Not sure what else it could be, you?  |
Not disagreeing with your empirical observations, just your analysis. I should just let this go, but the pedantic engineer in me comes out
The rest of you, feel free to whack us on the head.
Let's do the thought experiment. Is it possible to create a 1 cylinder engine that idles like crap with a big cam? Absolutely. Just put a big enough intake plenum after the throttle body, which can accumulate enough exhaust reversion to create the gagging effect that is lumpy cam idle. No adjacent cylinders needed
But in practice with a 1 cylinder engine, chances are the throttle blade is close to the intake valve, and the volume under vacuum when the overlap cycle commences is therefore very small. So the amount of reversion is correspondingly low. An ITB engine is just eight one cylinder engines.