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Comment by evo_9 | Hacker News Reader

Or not care since evo's and STi's launch faster than all but a few ferrari's. if you aren't at a dead stop the lag doesn't happen in real driving situations; aka you would have to shift into 4th under 30mph for example in either of those turbo charged cars.

The way my Evo seems to get around the dead stop lag - you floor the car and hammer the rev limiter and then basically bring the clutch out about a 1/4 inch then dump it. I hit 3.5 second 0-60 easily with this (standard) evo lauch technique.

Lastly you lose a lot more hp in a naturally aspirated engine at altitude too which to me makes a turbo car a better option ( I live in the mile high city however so this is a personal thing )

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Regarding the altitude comment, you're spot-on and one only needs to look to aviation to understand this phenomenon.

Absolutely, except launch control software is the one dumping the clutch for you in the Ferrari, so the 1 second of spooling is irrelevant for obtaining the 0-60 time.

I think he's speaking about the traction issue a Ferrari experiences during launch vs the Evo which has AWD and does not suffer from such problems nearly as much (except very high HP AWD cars).

Also, the 1-second of spooling may not fully occur during the hammering of the throttle until the clutch is dumped due to there being no load on the engine. You might get the turbo going some but it won't be generating the power it normally would when the car is actually moving. Since both cars in the comparison would be turbocharged then it would then come down to which car can get going quicker to keep the turbo going and that would usually go to the one that has the most traction.

Source: I own 2 Evos.

Won't there be lag when you go back on the throttle after you turn while off the throttle?

No. The turbochargers rotational velocity doesn't instantly drop to zero. Once the intake butterflies are back open and exhaust gas volume and velocity picks up the turbocharger is making boost again. You may be able to measure this delay, but that isn't turbocharger "lag". What people call "lag" is really boost threshold. It's the point in an engine's RPM curve at which the turbocharger can supply more air to the engine that it would have naturally. Natural in this case means atmospheric pressure. So 1 psi of boost is 1 psi above atmosphere. Likewise 1 bar of boost is twice atmospheric pressure.

Is what you're saying that the lag is actually the period before the turbo spins up and starts producing boost? In somewhat different wording, the lag is the engine running as if it were NA until the turbo can spin up to a speed that it will compress the incoming air? That's what I have always thought turbo lag is.

I thought turbo charger was the delay in throttle response. That's what wikipedia seems to think too: http://en.wikipedia.org/wiki/Turbocharger#Turbocharger_lag

but I guess in the end I see what you are saying and it's merely a matter of terminology

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