tuning with/or out secondaries

[ilovemycar]

Originally Posted by warmonger

In fact, that is one way to tell if you maf is dead and giving bad signals. You can unplug it and start the car. If the car runs better then you need to look into MAF related issues like vacuum leaks, bad mafs, etc.

That's how i figured out a couple weeks ago that a nitrous backfire burned up my MAF. The car ran like poop, and i looked at a whole lot of things. I then unplugged the MAF, and it ran pretty good so i went and got a new one.

[cpapashley]

Originally Posted by warmonger

No, the MAP system still works just not as exact. The tables don't change just the variables in the equation.
It will see the change because the MAP system will sense a change in pressure and temperature and therefore extrapolate the higher air density.
If the cold air system actually works then it would deliver cooler air to the engine. Lets assume that the manifold pressure stays constant, then it would still indicate to the PCM that the air is more dense because it senses cooler air.

So both systems work. However, have your temp sensor, or your MAP sensor, or your tps go out on your speed density car and the thing will amost not drive at all!
Go out to your MAF system and unplug the Temp sensor, or the TPS, and the thing will still run almost perfect but with a check engine light.
Or, assume all your sensors are working but the MAF is not. Then the MAF system will be able to revert to a speed density system through extrapolation of manifold pressure. It will still run reasonably well.

Go out and try it, unplug just the MAF and then start the car and watch it will run pretty good.
In fact, that is one way to tell if you maf is dead and giving bad signals. You can unplug it and start the car. If the car runs better then you need to look into MAF related issues like vacuum leaks, bad mafs, etc.

I will definitely try this out. Thanks for that tom. Helps me to understand a little better now how the map works, I can see how the cai would make differences in both iat and map.

I was looking at the airflow spreadsheet on your site and thought that it would make more sense to keep the secondaries if you had a max extrude honed UIM (I seem to remember mention of 193 cfm being the flow rate) rather than removing them. Would it not make driveability that much better? Or would the higher capacity of the 3.0l engine and resultant torque really compensate for this?

[warmonger]

With a 3L you have your choice. You can make the 3L work well enough without them. I also think you can keep them without any sacrifices either.


For a 2.5L, definitely Keep them!

[tony]

just thought i would say that i took mine out and it helped we done 2 runs and the engine breathed better with them out BUT mine is on a standlone menigment and other bits ...... so it wont be the same

also i filled the holes where the rods were with weild

[fordrule]

there was questions about secondaries so i bumped a old thread that had a lot of info from the resident tuner

[tour96se]

holy small ports..def'n not a svt or st200 manifold