Pressure

[konman]

Why does a boost gauge not read any positive pressure when you rev the motor in neutral, but when its in gear its reads positive pressure?

[Japmetal]

Is it an auto box? never heard of/seen that before [my brotehr has a Starlet Turbo which shows boost when revved regardless] so maybe there's some clever system telling it not to boost when out of gear ?

[Nick Mann]

I don't know the answer - but heres a bit of cow droppings:

If there is no 'drag' on the engine, then it will need much less fuel to rev. Therefore the exhaust gasses must also be much less. Therefore the turbos don't spin as much as they would for the same revs. Therefore boost pressure is much lower!

Ta-daa!!

Do you like it or not?

[Japmetal]

That also sounds reasonable :)

[konman]

I don't know the answer - but heres a bit of cow droppings:

If there is no 'drag' on the engine, then it will need much less fuel to rev. Therefore the exhaust gasses must also be much less. Therefore the turbos don't spin as much as they would for the same revs. Therefore boost pressure is much lower!

Ta-daa!!

Do you like it or not?

thats pretty good, still doesnt answer my question though.... car is an auto, maybe there is somesort of funky computer thingy... but i would like to know for sure.