Hi everyone,
Seems like every couple of weeks, the same scam items show up on the boards, I thought it would be useful to just collect all these scam items into a single thread, and maybe if it's good enough, it can be sticky (I don't know how that happens). Of course I wouldn't take credit for being the first person to point out these things are scams, but we just have to collect them in a single place.
If you post a product that you think is a scam, please give some reason why you think it is. I'm not trying to flame products, just figure this is the kind of thing these boards can be really useful for. Also, let's keep this thread about engine and driveline products (since this is where most of the obvious scams are)
Rule of thumb: If it's too good to be true, it probably is. (you think Honda engineers would not spend $5-$10 bucks to improve your power, increase your mileage, improve the driver's sex appeal? )
I'll start:
1. "Performance chips"
http://www.fitfreak.net/forums/fit-j...ance-chip.html
What I'm talking about:
I'm not talking about nice expensive tuning solutions, I'm talking about the ~$10 chip that shows up on eBay over an over, under various names and from various sellers.
What it really is:
Just a resistor attached to your IAT (Intake Air Temperature Sensor)
What it does:
Your IAT tells your Fit's computer the temperature of the incoming air. Increasing the resistance fools the computer into thinking that the incoming air is colder than it is.
What's really going on:
Your Fit's computer wants to match the amount of fuel it injects into the engine with the amount of oxygen entering the engine. The amount of oxygen entering the engine can be measured by measuring the mass of air entering the engine. There are several types of "mass flow sensors". They're different, but the important thing is that they cannot really measure how much air is going by alone. All of these sensors require a thermometer to correct for temperature.
When you trick the computer into thinking the air is colder than it is, it thinks more oxygen is going into the engine than really is.
The computer can react in a couple ways, mainly changing the amount of fuel injected into the engine and changing the ignition timing (when the spark plug fires).
The best that could happen:
Psychologically, it might feel like you're going faster. Heck, at some points of the powerband, you might actually make a little more power.
The worst that could happen:
1. Void your warranty.
2. Foul your catalytic converter, fail your next smog test.
edit: (downest correctly points out that this is unlikely, given that this mod probably does not have a large enough effect for this to happen. Running either rich or lean is at least not good for your emissions system)
3. Your engine will be running either rich or lean (it really depends on the situation), and so engine temperatures will be off.
4. Induce pinging as the ignition changes.
5. Damage your crankshaft, valves, piston rings, etc.
6. Kaboom.
edit: (again, downest points out this is unlikely. I agree, but you are messing with your fuel - air ratios, and in researching for this post I did find some people who had mechanics blame IAT mods for blown engines... I know I know, who knows about that, but it's possible. Again, this is the WORST that could happen)
If you are still not convinced:
One of the main purposes of your car's computer is to calculate how much fuel to squirt in your engine. Honda engineers with degrees and slide rules and computers missed family dinners to calculate how much gas to squirt into your engine in almost any situation, while taking into account performance, fuel mileage, and engine wear. All they ask is that your IAT tell them the correct air temperature. Are you really going to take this away from them?
...and for what, for some random change to your detected intake temperature?
At the very least, it's a scam because you can do it yourself (if you really want to) for a penny resistor, and you should at least know what you're doing and why you're doing it.
(While we're at it: let's just point out that any product that purports to be a "chip" and increase performance and has fewer than four wires is almost certainly a scam. Chips need at least four connections: power, ground, signal in, signal out. Fewer than four wires? It's a passive: resistor, capacitor, diode, or maybe just a wire in a plastic box. I don't care how many knobs, lights, or what have you are on that box, two wires but claims to be a chip [just to make it sound fancy]: it does nothing.)
2. "Electric superchargers"
http://www.fitfreak.net/forums/fit-j...c+supercharger
http://www.fitfreak.net/forums/fit-j...c+supercharger
What I'm talking about:
Any product that tries to increase induction (the amount of air going into your engine) using an electric blower.
What it really is:
A surplus electric blower that someone slapped some ducting (the same size as your intake) on. Ok, that was trite, maybe it's a super fancy, proprietary blower.
What it does:
Blows air into the engine, and the best part is: you don't need to do all the plumbing of a turbo, and you don't have the parasitic losses (power loss because you're blowing air into the engine using engine power) of a supercharger.... that is, until it can't keep up with air demand of the engine
What is really going on:
Sure, electric fans can blow air, wow, just check out how much air that hairdryer blows!
The question is: can an electric motor blow enough air AT PRESSURE to make a difference?
I just typed out a bunch of volume and pressure calculations but they were a mess, and I realized there's an easier way to make this point.
Superchargers use around 10-20 hp from the crank to drive them (maybe someone from AJ Racing can confirm this). Some estimates go even higher.
You can check the math yourself...
1hp = 746 Watts.
See where this is going?
So for a modest boost, an electrical supercharger is going to consume around 7460-14920 Watts... ~12 kiloWatts..... granted that's less than the 185 kiloWatts max power of the
Tesla Roadster, but this is just for a supercharger!
For comparison, starter motors use about 100amps, at 12V this is 1200 Watts, so 10X the power of your starter motor...
and by the way, you can play all the games you want with stacking motors etc., this has nothing to do with it. This is the power necessary to compress gases, there's nothing magical about it. All fancy motors and fans will do is increase the efficiency by which the supercharger compresses gases, not decrease the amount of energy necessary to do so. When you compress gases, the temperature increases. The supercharger or turbo has to put that energy into the gas, and if it isn't supplied that power, there's no way the gas will be compressed, no way for the boost to be achieved. We don't need dyno charts, we just need a little thermodynamics.
So until you see a 12kW electrical supercharger (and those are big industrial motors you're talking about), you're not going to see results comparable to traditional turbos or superchargers.
The best that could happen:
That being said, eRam says their supercharger uses 791 Watts, and it only comes on at peak throttle. It's probably because even at only 791 Watts, it probably generates enough heat to destroy itself in short order if it had the duty cycle of a traditional turbo or supercharger. (we didn't talk about power dissipation problems of the electric motor...confirmed, 800 hours before service.). They say +15hp. That translates to what, <1 psi? sure, maybe... but what's the point? These gains are only a few percent better than an intake with no fan in it. Their claims are so small, it's hard to dispute them.
The worst that could happen:
This is the good part: probably nothing...
Maybe fry some wiring. Perhaps you'd have to bear mocking from us and your mechanic.
If you're still not convinced:
One main points of an electric supercharger is to avoid parasitic losses (I guess also cheaper). But ask: Why there are parasitic losses? Because it takes a lot of power to compress air! Why are superchargers and turbos expensive? Because they have to spin at such high rpm and deal with so much power while compressing air! A 791 Watt fan, while impressive, comes nowhere near the power supplied to a turbo or supercharger.
If you could put out the power needed for compress the necessary amount of air (for let's say 5psi) in as small a motor as is mounted on these superchargers, you could put one in each wheel hub, lose the ~100 whatever lbs. of the gas engine, and have a car with almost the same power as our stock fit. So enough the the electric superchargers, bring on the perfect electric car!
Wow, that took a lot longer than I expected.
To come: magnet madness, intake vortex tornadonators,... if anyone is curious about a product, post it here.
Linear Mode
