Miata Turbo Forum - Boost cars, acquire cats.

- Prefabbed Turbo Kits (https://www.miataturbo.net/prefabbed-turbo-kits-3/)

- - Elusive fuel (https://www.miataturbo.net/prefabbed-turbo-kits-3/elusive-fuel-82323/)

Quote:

Originally Posted by leboeuf (Post 1191218)

Good grief wft is going on in this thread. I've now realized that either the automotive world has hacked up normal engineering terms to where they make no sense, or that everyone is just generally confused...

So PWM: Classically PWM is a means to control average current to something with a purely digital system. In a valve you set a fixed frequency that is much higher than the valve can physically operate and control the duty cycle of that digital signal to control the average current to the valve. This average current control allows analog control of valve position with a digital system.

WTF is going on in the car world? I see people talking about PWM being a digital signal and that the injectors actually go binary and completely turn off/on with the PWM signal? I think the MS3 is set to 60us PMW freq? I don't see a $100 mechanical valve operating at 60us...

It's like I'm at work looking at a marketing hack job of my project.

PW, not PWM. The signal going to your injectors is a binary on / off signal controlled by the ECU based on fuel demand calculated from air flow if using an air flow meter or calculated from RPM and manifold pressure if you have converted to speed density. This binary signal is expressed as pulse width (PW) and is a direct measure of how long in milliseconds the injector is held open, or as duty cycle (%DC) where the number of milliseconds the injector is open is divided by the potential number of milliseconds the injector could be open at that RPM.

Keith

PS: Somebody probably already said this... answering as I catch up in the thread.

Off topic...
Honeywell TDC 2000, TDC 3000, PMX, Modicon, Triconix, and DEC servers running level 3 applications.

OOPS I dropped a chipotle citrus boneless chicken wing on the keyboard an in cleaning it off I posted in this thread.

Thar's too much stoopid up in dis bitch, I aint commenting. If someone wants to math to show how all this actually relates I already posted most of it in the A-O thread.

Quote:

Originally Posted by Leafy (Post 1193058)

I am with you. Did you notice that my posts in this thread were only tangentially related or totally unrelated to the OP's topic?

Sad when a topic is so beat to death that going off topic is a point of pride.

Keith