so as i changed mods on my car that is why the vacume increased with my cai.i used to get 23-24 now im pushing 26 on vac guage because there is more air rushing throught the intake right
151 smile.gif

 

So, if there is Zero vacuum in a intake manifold when the car is floored...the air just goes into the engine because I told it to? Because I asked it really nicely???



No, I do get your point Red, but, I've been doing some reading up on their website. They seem to use the same darn chip for every car, just different internal programming, and different wiring for the install...so it must be able to adapt between MAF and MAP.

Following Zorro's advice and getting the interals re-programmed for a MAF rather than a MAP sensor should take care of any/all snafu's in the programming. As to how to wire the damn thing...good luck, but I'm guessing it connects to the same or similar wires as the SAFC.

 

Elantra -- if you're pulling MORE vacuum it's likely because something isn't right or you just measured between a cold engine and a hot engine. Typically more mods equates to less vacuum.

Random -- Lots of things.

First, when you floor the car completely to Wide Open Throttle, there is zero vacuum on the manifold (relative) because the throttle plate is completely open. Rip your boost gauge out of the car for a moment and stick it on someone else's car (it doesn't matter what car, just so long as you can find a vacuum nipple to "borrow" for a moment).

What happens is this: when the piston is moving downwards on the intake stroke, it's creating suction (vacuum) which draws in air. If you stick a vacuum gauge (a manifold absolute pressure sensor, or MAP) on the intake manifold, you'll see that a very large amount of vacuum is created because the pistons are pulling against the closed throttle plate. At idle, the idle air control valve lets a bit of air go past, but certainly not enough to make up for all the air these pistons *want*. This is why your car doesn't create full power at idle: you're compressing less than a full cylinder of air.

If you hold the throttle wide open, the pistons are able to suck against a (mostly) unrestricted source of air. There will always be a tiny bit of vacuum if you measure close enough, but it's almost invisible to the naked eye on a normal vac/boost gauge. Air goes where it's supposed to because the cylinders are sucking it in, but nothing is prohibiting the cylinders from getting that air.

Make sense now?

-Red-

 

Oh whoops, forgot this part:



Do you know anybody in the States that can reprogram Zoe's chip? I'm guessing there's someone out there, but I don't know where...

-Red-

 

Sorry, I understood about the vacuum/throttle thing, but I wanted you to say it because you can explain it better than I can. I tried it over at HP.com yesterday, and did a poor job of it.

Yes, ICON has dealers/tuners in the US of A...but none in Cali eek.gif (Can you say NOT CARB approved!)

 

Sounds confusing about but I think I understand. I would have assumed that the ignition timing data from the ECU to the plugs would all be in the same 'language' that the ICON would replace with its own instructions?

Ah, I see what you are getting at - different ECU's different 'language' smile.gif

Didn't need the vacuum explaination really.

Red, you are such a nosey smart-arse tongue.gif, but thanks for pointing that out...I'd forgotten that the US and UK tibs would use different ECUs smile.gif

[ December 18, 2001: Message edited by: Zorro ]