yep...but if you're slowly getting into WOT you'll still get boost at WOT

 

cool, thanks for the info guys, i always thoguht it was RPMs......

 

He said 10 psi vacuum. Turbochargers displace positive pressure, no?

 

Unless the turbo is spooled you still have the engine sucking hte air in. Boost only kicks in once the turbo is spooled, but when cruising it isn't, so you do have vacuum.

 

TPS = Throttle Position Sensor. Reads from 0-100% 0 being closed.

Kedawei - An engine is an air pump, with each combustion it creates a low pressure area inside of the cylinders thus drawing air and creating a "vacuum" condition inside the intake arm and intake manifold. Don't take that as meaning there is no air, it just means that there is less air than the universal standard of 14.7 lbs per square inch.

Ever wonder why the Honda MAP sensor is a 1.7bar map sensor and can only read 11.2 psi before it no longer reads? 1.7 bar = almost 25psi!! This is because WOT in an N/A car = atmospheric pressure or 1 bar (14.7psi). When the throttle is not completely open the intake manifold cannot bring in enough air to reach 1bar thus sustains a state of vacuum (less than atmospheric pressure) that is read in inches of vacuum, much like a barometer.

As for something I just caught in the very first post, reffering to tire sizing. first/second/third 200/50/16

First - 200 - Width of tire in mm
Second - 50 - Tire height, stands for the percentage of the first number. In this case the height of the tire would be 100mm
Third - 16 - Rim size that the tire will fit

 

sov...i know about the tire size...and all, but he was trying to argue it the other way around....so thats why i was kinda sketchy on his idea of driving in vaccum.... also. are you saying that the stock MAP sensor is good for about 25psi of boost?
thanks

 

Read what I said carefully about the MAP sensor.

1.7bar = ~25-26psi

1bar = atmospheric pressure, also known as "0" on a boost gauge. In other words the intake manifold is perfectly balanced with the outside atmosphere.

so since 0 vacuum = 1 bar

1.7 - 1 = .7bar left

The stock Honda MAP sensor only has .7 bar or ~12psi left to read after the intake manifold has reached 0.

Make sense?

 

yea, i was going to throw in the atmospheric pressure bit too...but i couldnt word it in a way that would make sense...so 12 psi should be good enough for me so stock map is good to go...(untill i get bored with 200-250...lol) sov....your just TOO DAMN SMART!

thank you again for clarifying yet another issue for me.

 

10psi would constitute spooling.

 

Good info Sov, never knew all that. By your numbers .7 bar would equal 10.29 psi.