I used to own a KA24DE-T, so im familiar with boosted applications, but i was curious as to if you had the right bank turboed, and the left bank left with a manifold/header (no turbo),
what effects would that cause? all cylinders would share the same boosted pressure, as there is just one throttle body..
just kinda making a small blueprint out, and was wondering if i could get some opinions from you guys
thanks
VH single turbo question // thoughts
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TXCumtrensh
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Re: VH single turbo question // thoughts (TXCumtrensh)
(Disclaimer - post based solely on a few seconds of thought)
You need to shift enough air to feed 4.5 litres but only have 2.25 litres of exhuast to do it with, effectively youre turbo sees itself as very inefficient. The pressure differential between inlet and exhaust on the turbo side will be large, promoting exhaust to backflow past the inlet valves into the intake manifold. So you have to use cams with zero overlap on the turbo side, if not the whole engine. The gains from the boosted side that doesnt have the backpressure from a turbo will be lost from the boosted side that has 2x the backpressure.I cant think of any real gains to be had from this setup, when you could just run a crossover pipe and have 8 into 1 single turbo operation. Twin turbo seems more balanced and asethetically pleasing but one big turbo would be big power option.
You need to shift enough air to feed 4.5 litres but only have 2.25 litres of exhuast to do it with, effectively youre turbo sees itself as very inefficient. The pressure differential between inlet and exhaust on the turbo side will be large, promoting exhaust to backflow past the inlet valves into the intake manifold. So you have to use cams with zero overlap on the turbo side, if not the whole engine. The gains from the boosted side that doesnt have the backpressure from a turbo will be lost from the boosted side that has 2x the backpressure.I cant think of any real gains to be had from this setup, when you could just run a crossover pipe and have 8 into 1 single turbo operation. Twin turbo seems more balanced and asethetically pleasing but one big turbo would be big power option.
Re: VH single turbo question // thoughts (Nyloc)
Quote »promoting exhaust to backflow past the inlet valves into the intake manifold.[/quote]no ... high to low ... not low to high
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mtcookson
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What he said was right. The pressure in the exhaust system before the turbo is much greater than in the intake so exhaust could get back in to the intake. That's why turbo setups like having low overlap cams to deter that.
If going N/A, the opposite is true. You want some more overlap and if done right, the exhaust can actually cause a sort of vacuum in the chamber, sucking fresh air in. This is how its possible make the volumetric efficiency of an N/A engine hit 100% and more.
If going N/A, the opposite is true. You want some more overlap and if done right, the exhaust can actually cause a sort of vacuum in the chamber, sucking fresh air in. This is how its possible make the volumetric efficiency of an N/A engine hit 100% and more.