cps87rx7se

I dont know for sure, but some correct me if I am wrong. But the compressor wheel is not spinning very fast, and therefore is not making any boost that the motor does not need.

RussellTT94

yes, the compressor is still pushing some air. the 'boost' is a measure of the pressure in the intake tract. at idle the engine is pulling vaccum, and is not pressurized enought to read 'boost'.

nismo convert

[quote name='Jedi' date='Apr 21 2005, 07:55 PM']Ummm.... Not sure if this is what you want to hear but you start making boost when you hit the accelerator. If you are cruising at 2k rpms chances are you arent on boost. If you punch it then you start to boost up. Depends on the load I guess. If you are in neutral and rev up to boost it will kick in at about 3.5k.


[/quote]





how would it depend on load?!?! if you floor it is just come on quicker because you get to that rpm quicker.



and boost not under load?!?!? with a stock turbo i don't think its possable!! i only get to 0psi.

Shane.Trammell

so if i had something pushing 2 psi into the intake at idle would that be alright? the psi will increase with rpm, but i dont know the numbers yet.

nismo convert

i don't know how your getting boost at not underload? but if you rev it you should only get less vacuum NOT boost!!

drunkin_idiot

YA when you rev at idle you get 0vac but also 0psi, it just goes to 0.

RussellTT94

do you even understand how a turbo works?



http://auto.howstuffworks.com/turbo.htm

nismo convert

who are you refering to?

roadkill669

Shane, it will not hurt the engine at idle as long as you have the extra fuel at idle. It will most likely make your idle higher.



I know I could boost in neutral. It was only a few psi, but it still boosted. At idle, you only pull vac. because your TB is closed.



Jedi is correct. The load on the engine will determine the speed of the turbo spinning. Thats why you can only get a few psi in neutral and any amount in gear at WOT. More load = more exahust pressure = more boost. Pretty simple.

1988RedT2

Yah, where is your gauge tap? I have a hard time believing you've got any boost at idle. I'd say your gauge is bonkers.