Cold air intake. Before & after.

[1994_4x4]

I wouldn't go that far yet. At the very least it is not any better than it was stock. The big thing to remember is that intake system mods can help when done correctly, but to really get any useable benefits you have to mod the head and exhaust to be able to keep up with the flow. It's a system, not a pile of parts.

What all do you recommend being done to the head? I've been told to port and polish the exhaust side and machine it. I thought about taking it off when I do the timing belt. I really can't do anything to the exhaust plumbing besides a h/p muffler. It's got the OEM header straight back to the OEM muffler.

 

[shane96ranger]

It's got the OEM header straight back to the OEM muffler.

No cat?

 

[bobbywalter]

i never cease to be amazed.

 

[adsm08]

Port and polish is always nice.

And for Pete's sake put a MF'ing cat back on it!!!!!

 

[Bob Ayers]

While this is true the problem with most of these "CAI" setups is that they change the diameter of the tube across the board. Since the MAF is not sampling all of the air coming through the tube, and is calibrated to take a percentage sample (usually about 10%) screwing with the amount of air coming in by changing the size of the duct work changes the sample rate. Changing the sample rate changes the accuracy of the air/fuel calculations, which in turn can cause drive-ability issues, generally resulting in a lean condition.

Look at my previous post, the problem with the larger diameter intake tube is the lower air velocity for a given air flow. With the lower air velocity across the MAF element, the signal going to the PCM is lower, which indicates a lower air flow then is actually flowing (hence - transfer function is screwed up). The MAF element is heated, and the air passing over it cools it, causing a change in resistance, which also changes the voltage drop from a constant current source.

 

[triumphrider-1]

The diameter at the MAF is fixed (unless you bore it out, which WILL screw with the readings), as is the delta P from the motor. Culverts on either side will have very little affect on the MAF.