http://www.slponline.com/view_product.asp?P=63010

I am purchasing a 160 Thermostat and a manual fan switch from SLP....and then I ran across this cheap part. Is it worth buying?? What will it do exactly??

Thanks in advance,

James

 

It basicly fools the computer into thinking the engine is getting cooler air than it actually is. Thats why alot of guys move the IAT (intake air temp) sensor closer to there air filter because its a coupel degrees cooler there than at the front of the engine.

Josh

 

I would just get a tune from madz28 instead of wasting money on that. Also he can program when the fans come on so you wouldn't need the switch ethier.

 

It tells the PCM that the air charge coming into the motor is cooler, and because of how the PCM is setup, (tuned from the factory) the cooler the air it sees coming in the more spark advance it gives. Spark advance will get you a little more power as long as you don't advance it too much and get detonation.

At least that's how it's supposed to work. I'd say you'd see little or no gains.

 

Don't buy one, it won't help.

 

Basically what all this advise amounts to is do not buy anything meant to trick the pcm. You could easily spend hundreds on carp like that when instead you could get better results from a $50 reprogram of you pcm. The aftermarket has got to hate these sites because we know their crap is designed more to remove money from your wallet than make your car faster they make big promises for simple things to install and sure some work maybe only temporarily though till the pcm sees what is going on. The real kicker is how cheap custom tuning is and how it can do everything they try for plus some.

 

could this thing hurt your car if you drove in extremely low temperature conditions?

 

That is a huge waste of money. Even if it did anything, you could buy a .99 cent pack of resistors from radioshack that would do the same thing....

 

No gains, get tuning: www.madz28.com

 

People can argue that simple mod will boost hp all day but the fact is the computer doesnt adjust timing or adjust fuel based on the AIR TEMP... but on the COOLANT TEMP! So you can see how youre wasting money buying that.

Dont get me wrong though.. the theory behind that mod probably works on other vehicles. Problem is the generalization that all computers work the same which is obviously false.

 

Cooler air will mean more fuel.. not that it will be anywhere close to a noticeable gain, though. That's what the IAT sensor is there for though, with that and the MAF the computer can make an accurate decision about the mass of air entering the engine.

But anyways, I concur, get tuning, don't waste your money on cheap tricks. You'll just be wasting time and money.

 

Thanks a lot. Yeah, I didn't order anything yet...b/c I was waiting for some replies. I figured it would be a waste of money, but wanted to check with people who knew more about it than myself.

~James

 

The PCM does not need IAT to get the mass air flow rate. The MAF sensor has internal temperature sensing that allows it to calculate the mass flow rate, and it supplies the mass flow data to the PCM with no farther need for anything except the MAF calibration table in the PCM. Later model GM MAF's incorporate a single IAT sensor within the MAF, with a secondary output of IAT to the PCM, eliminating the extra IAT sensor in the ducting.

Has it been conclusively shown that there is no table in the PCM that adjusts timing based on IAT? I though some hackers attributed the mysterious 3deg of advance that comes and goes in the PCM's timing signal output (difference between timing from the table and the otput signal) to an undiscovered temp vs. IAT table. Since I haven't used the stock PCM in more than 5 years, I'[ve lost track of what may have been learned since that time.

I know with my aftermarket ECU, we have timing offsets for both coolant temp and inlet air temp.

 

Scrolling down thru the tables they all list coolant temp as the temp variable. I can see why GM would do this. If you ever sit at a stop light on a hot day it becomes pretty obvious... heat soak will alter the readings dramatically. Coolant temp however is directly related to the ambient temp MOST of the time.

I have never seen or heard of that missing table. Tunercat has uncovered several extra tables in the least year or so and that one still hasnt shown up. I just learn to tune around it...

 

When I was running the stock setup, I could feel exactly what you described sitting at a light in stop-n-go traffic, in very hot weather. It seemed to suck the life right out of the engine, and provide a rougher idle. But if I looked at what was happening to the engine, it was the IAT that was heat soaking, reaching temperatures as much as 40-50degF above true ambient. The coolant temp wasn't changing much at all. Relocating the IAT sensor away from the engine seemed to eliminate the problem plus it made the IAT readout a better "outside air temp" indicator .

Just a thought.