View Single Post
Old 10-27-2011, 01:16 AM   #1547
renyo
Scooby Newbie
 
Member#: 93577
Join Date: Aug 2005
Chapter/Region: MAIC
Location: Chicagoland
Vehicle:
98 Impreza

Default

Quote:
Originally Posted by 99ForesterVA View Post
Thanks for that response. That was what I was looking for. My main issue is understanding exactly how the snorkus works, and what the purpose of the MAF is. I know from williaty's responses that the MAF meters the air. What is the main purpose of the snorkus though? Is it to allow a certain amount of air into the intake?
As williaty said, the snorkus is there to control a resonance issue with the MAF. As a byproduct, it reduces air flow slightly.

Quote:
By the way, I will using williaty's hybrid intake template for mine. I was 99.9% sure before, but I wanted to test some other theories too that sounded good. I saw a picture of a short cowl induction on another forum, and thought about trying it.
If I understand you correctly, it's known as a gravelsports intake. You can't do it with a MAF.

Quote:
Just to make sure you understood what I was talking about, let me repeat my idea, adding the info I've learned here.

1. Since the engine sucks it's own vacuum of air, I thought about a cowl induction system where (a) either I would leave the rear airbox in its original place, and run a 90* elbow out of the side and through a hole in the firewall, drawing air through the cowl area, or (b) running a pipe straight from the intake into a hole in the firewall, and deleting the rear airbox and adding a filter inside the area where the windshield wipers are located or in the pipe area between the intake and firewall. As I understand it, there is plenty of air pressure at the base of the windshield to be sufficient for the intake. The only issue would be rain or snow accumulation in that area, and risk of hydrolock if some were to get in the motor.
If you have any kind of hole or membrane permeable enough for air to flow through it after the MAF, you're going to have problems.

Quote:
2. As for the MAF, I was considering leaving the original snorkus and airbox and MAF section as is, and placing an air filter right after the MAF section. Since it has been established that the engine is what draws the air through the MAF, that idea is out the door.
I think the idea you're missing is that if it doesn't go through the MAF, there's an issue. It doesn't matter why it doesn't. If it doesn't, you're going to have a problem.

Quote:
I thought that if the air going past the MAF did not have the vacuum from the engine, then my solution to the MAF causing the car to run lean would be brilliant. But it seems like, if anything, if I was going to be hard-headed like some people are, I'd be better off taking the whole shebang out and there'd be less issue than if it was getting a false reading from not enough air with my set up. I have no intention of doing that however.
A MAF is like any other scientific instrument. Aside from the occasional mechanical or electrical problem, it doesn't make the car do anything. Basically, the MAF isn't a problem that needs a solution. The engine expects the MAF to tell it how much air is coming into the engine. If you prevent the MAF from doing it's job, you prevent the ECU from doing its job. When the ECU doesn't do it's job properly, you have engine problems.
  • all the air, and only the air, entering the engine must pass through and be recorded by the MAF
  • all the air, and only the air, passing through, and being recorded by the MAF must enter the engine.

If either of those two rules are violated, you're going to have issues.

The snorkus is there to make sure that all the air recorded by the MAF is actually entering the engine.

It's bedtime, forgive grammar issues.
* Registered users of the site do not see these ads.
renyo is offline   Reply With Quote