Chechen_Jeeper

Hey all,

I am new to this forum, I am not really sure if this post fits in this section, but I am sure the Admins will fix it if I am wrong.

Let's start off,

I am sure all of you have seen the "Chips" that are supposed to increase horsepower by 50+ and torque as if that chip is a replacement for a stroker or forced induction, unless this chip is a programmer, that rewrites the maps carried by the PCM, there are mostly just resistors that are connected to the IAT or Coolent temprature sensor.

Now, most of these are overpriced for the packaging and many poeple have called it a gimmick.

However, a while back I saw an add for one of those for around 4 dollars, I figured Id give it a shot and test for myself. I ordered 2 so that if it did infact work, id give one for my brother.

All I received was a resistor, in an envelope. But, what the hell I installed in into the IAT.

Much to my surprise, it did actually provide some power.

I did some more digging into the matter, used a scanner. Without the resistor, the IAT read 73 degrees Celsius, far different from the ambient 32 degrees. with the resistor, it read 51 degrees, which was closer, but still far from the ambient temprature. at that setup, i felt better acceleration, and faster high speeds, ( after the 100 Mph mark, the needle just dives into the blackness)

I figured that the location of the IAT was right over the exhaust manifold, giving it a higher temprature due to engine heat. and Ive also heard of people gaining power from relocation the IAT to the Air intake box.

I figured, if 50 degrees gave more power, what would less temperature do, so I wired the resistor in series with the IAT sensor wiring. The result, even more power.

If you have a cold air intake, I beleive it will help even more.

This resistor can be bought by the pack of 15 for the amount of 2 dollars where I live, I figured I'd share my experience with this for the other jeepers around, because I sure as hell would have loved this information before

I hope this helps,

Cheers

askingxforxit

Get a bored throttle body and a true cold air intake. No matter what high flow filter or intake you have, if its in the engine bay its not a cold air intake. Snorkel and cowl intakes are though because they draw air directly from outside.

dave1123

What's the value if the resister in ohms? If you don't know, give me the color bands. Also the diameter would help. The IAT is a thermistor, or temperature controlled variable resistor. A good service manual should show tests of resistance at various temperatures. If you wire your resistor in series or parallel will make quite a difference!

If the PCM thinks the intake air is frigid, it will dump more gas into the mixture. More gas, more power, less mpg. Don't know what the 02 sensor will think of it.

askingxforxit

The resistor is only fooling the pcm of the inlet temp. I wouldn't put one in.

dave1123

How about setting it up as a booster circuit, like a nitrous button.

askingxforxit

I think in the long run it'll cause more damage. If its power you're looking to get from the I6 then stroke it to a 4.7 with full exhaust, bored tb and cowl intake.

dave1123

Personaly, I wouldn't put all that money into what amounts to a tractor engine. The 4.0 as it sits, is a good reliable powerplant. Any mods to it only shorten it's life.

As the British say, "If it works, why change it?"

askingxforxit

Intake and exhaust isn't going to hurt anything and will help prolong the life of the engine. Stroking it can possibly shorten life depending on the parts used and who is doing the work.

Chechen_Jeeper

Alright, Ive just taken a picture of the resistor, with my thumb there for reference in terms of diameter. This is on the IAT, as you can see I spliced the wire going to the sensor and added it in series, since the IAT is a variable resistance sensor, this helps as it will somewhat correct for different tempretures rather than having a set one

I think it all compliments the other

I have a cold air intake, bored throttle body 62mm, almost straight pipe exhaust say for a cross pipe muffler ( similiar to the original XJ exhaust muffler, but a bigger diameter) I had to add and a muffler tip to reduce the noise ( the muffler actually restored quite a bunch of low end torque while preserving high end horsepower). I also programmed my jeep with the hypertech power programmer medium power setting. The air flow is quite high and nice, which I believe with more gas and a bigger spark will give better performance.

Also, I have both O2 sensors removed, Jeep runs like a charm and with much better milage from when it was stock.
The only problem Ive had with this setup, is my tires requiring a change sooner

Im thinking my next upgrade will be doing something similar to the coolant sensor

Chechen_Jeeper

I also like the booster circuit idea, maybe il do that for the coolant sensor

dave1123

Solder those wires! You're only dealing with 5 VDC so connections are critical. I'm assuming in the UAE, you can get away without emission standards?

That's a 3.3K ohm 5% resistor.

Chechen_Jeeper

Yea, unless your engine is burning oil or is severely in need of disposal, passing emissions is easy, oil leaks, body, chasis and brake integrity is harder.

Yes, checking the color bands on that resistor gives back the amount you reported.

Today, I fashioned a similar device to control the coolant temprature sensor readings, Il post a write up, and possibly upload a video, as soon as I have the time

dave1123

Without emission standards, you can go to a bored throttle body, V8 injectors, and remove the catalitic convertor. Should make a substantial difference.

Chechen_Jeeper

Bored TB Check
Decattify, check.

Injectors, need to regulate Fuel PSI, dont know how to do that