>bury the gas pedal >boost finally builds up an eternity later

Oh hey, 1980s.

>when the engine doesnt respond to the turbo request

>>16876263
When will this meme die? Simple physics dictate, there will be some sort of lag, unless you are running an anemic tarbu boosting piss from low revs or twin charging.

>>16876443
Theoretically if the turbo was efficient enough to produce the desired boost at low exhaust flows...

PV=mRT right? Double the temperature could THEORETICALLY double the inlet pressure (assuming one "lump" of exhaust can cause the turbo to take in an extra "lump" of intake air), 14psi boost across the entire rev range.

However we're not even close to theoretical limits.. Not sure if we can be, might be missing some non-regenerable losses.

Any actual science behind why boost delay exists? Why can't the turbo produce boost at any rpm? Should be proportional right? Where is the loss?

>>16876251
>>boost finally builds up an eternity later
That's what you get for building a dyno queen. Size your turbo sensibly and don't set stupid power goals and you'll wind up with something driveable.

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>>16876443
>twin charging.
Best turbo engine reporting in

>>16877186
>Any actual science behind why boost delay exists? Why can't the turbo produce boost at any rpm? Should be proportional right? Where is the loss?
How can you be this dumb?
Turbochargers are designed to produce large amounts of mass flow at relatively low pressures, using small low mass compressor and turbine wheels. This means that they must spin quite fast to generate said flow. Even though they are low mass and their inertia is low, they still take time to spin up from a couple of thousand rpm to several tens of thousands when the throttle is open. Spooling is also a feedback loop, when you go to WOT at low RPM, exhaust volume is initially small and relatively low velocity, but as the turbo produces more flow, exhaust volume and velocity increases, and the turbo can spin up faster. This is why your average turbocharged car is in boost very quickly when you downshift in a relatively high load condition such as cruising at a high speed. The engine is already doing a decent amount of work, so exhaust volume is not so small, and with the higher engine load and rpm the transient response is made faster by the faster rate of increase in exhaust flow.

>bury the gas pedal
>nothing happens
>the car isn't running
>i'm 9

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>pin it in 2nd gear at 3,000rpm
>2 second delay to full boost

>>16877266
Twin-charging != twin-turbo

>>16877327
I have an N55 so it's twin-scroll, that said I got my terminology mixed up. Either way, no discernible turbo lag

>he doesn't have a top tier anti-lag setup
lmaoing

>he doesn't like feeling the foot of God kick his car in the ass at 20mph

>>16877282
Think of a single cylinder cycle, though:

Air goes in, more volumous air comes out OR higher pressure air comes out.. Has to be one or both of the two since it's hotter and fuel has been turned to gasses, right?

That means that the exhaust air should be able to do more work than it takes to produce the inlet air.

This is all at theoretical maximums, of course. There are losses, I'm not that dumb. But why is it that an engine taking in X amount of air and exhausting X+Y amount of gasses can't then use that X+Y to intake X+Y. Theoretically, a perfect system would overrun itself at idle, because the next cycle would have X+Y intake and exhaust X+Y+Z, which means the next cycle could intake X+Y+Z.

So my question is actually: why are turbos not able to produce boost at low turbine speeds? Higher speeds means higher air flow, but the engine would also be taking in much more air.. Meaning the pressure shouldn't change. But it does. THAT'S the part I don't get.

Same goes for superchargers. They're positive displacement ffs, their air flows are directly proportional to engine speed which is directly proportional to mass flow rate. Why does boost pressure INCREASE at higher RPMs even on a supercharger? Why aren't boost pressures always steady? What makes it non-linear?

Turbos aren't perfect, so there's losses that mean a slow exhaust can't spin the turbine efficiently and so low boost.. Higher exhaust pressures/volumes make those losses more negligible and you start to see boost? They're also centrifugal instead of positive displacement which is a velocity thing..

This is what I meant by the science behind it. Not just "no you dumb fuck because turbos have lag". You said things happen certain ways without actually explaining why.

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>>16876251
>bury the gas pedal
>remember that i have a 1JZ with VVT-i
>remember peak torque at 2500rpm
>boost achieved while mildly accelerating to 40km
feels good man.

>>16876251
>bury gas pedal
>na v8
>instant sideways at any speed up to around 70

Don't just bury he gas pedal

>>16877418
This. This is the fun of a turbo car.

>>16877471
All of my wat

>>16877266
Not best but most useable. I have a 2.0T Audi and it's bretty gud. Would prefer my grandads 6 3/4 twin turbo mulsanne speed though. It's so smooth.

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>bury gas pedal
>ass end hangs out

I hate hate hate when GTRs do this. My Subaru used to do this all the time, was kinda scary at intersections when you're trying to make a left in heavy traffic.