Ebay Speed Chips...

Whenever I browse Ebay I often see things for sale called "Speed Chip +20HP!!!" I find this very hard to beleive, it says it messes with the air/fuel ratio by simple placing it your IAT sensor... well anyways they are extremely cheap and I would definatly buy one, but It seems to good to be true. Has anyone here had one of these, if so, does it cut your MPG or hurt your engine?

first of all.. those things are not chips - they call them chips but they are resistors. let's think about what this is actually doing.

your IAT or inlet air temperature gauges exactly that - the temperature of the air that is entering your intake. Warm air is LESS dense than cold air - therefore more warm air is required to maintain the stoicometrically correct air/fuel ratio of aprox 14:1 (someone on here had a more exact figure but whatever it is..)

With this "resistor" that they sell on ebay - the only possible thing you could be doing is "tricking" the IAT into thinking the air is colder than it really is - the result? the ecu is tricked by the IAT that their is plenty dense air outside - so what does the ecu do in response? - it dumps more fuel into your cylinders. If you are doing this on a day where it is actually sorta warm outside - you'll be running your car very rich.

I wouldn't touch that shit EVEN with someone elses car. not unless I had done heavy mods and for some reason needed to run a lil more rich at idle for cooling - and even then I would only match it up to an according resistor with something that datalogs. In fact - i just wouldn't do it, no matter what the case.

if you do want one - just research what resistor to buy and spend 30c on it at your local electronics store. any price on ebay is a rip off.

also see my post here - about the actual socketed/unsocketed ecu chips - cuz i'm sure that will be your next question (;
http://www.automotiveforums.com/vbulletin/showthread.php?t=331107

like ludeguy said in a previous post just because the 'chip' says it raises ur redline to 10,000 it doesnt mean that ur engine is meant or can withstand that level of RPMs

Chipping rules ~ you can modify nearly every single value you want. However, I call the ebay chips (JUN, Mugen, Spoon..) "blind tuning". Its similar to buying a used VAFC fuel computer, installing it, and then leaving it at the previous owner's settings. You need it tuned for your application, not someone else's. Although I imagine the JUN program works fantastic on a JUN tuned H22; just not mine.

A similar note, I am all for socketing/chipping. This is the basis for how Hondata and Uberdata works. If only I had an EPROM burner, I'd be tuning daily.