I see them here:[url]http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33597&item=2421985262[/url]


Is it just a gimmick, or things like this work at all?

Not nearly as well as they claim -- in most cases you may find yourself losing HP because the timing gets advanced so far that it begins to knock, which then leads to the knock sensor cutting power to the motor.

If used in a properly tuned system, yes they will deliver performance gains.

On turbo cars they do wonders -- so long as you don't try to over do it.

Ed

Not sure I would trust much from an Ebay vendor though....maybe Superchips, Hypertech, etc...

About the only way you'll get one that works (well)is if you go to a shop that has a dyno and a chip burner. (and people that know how to use them)

only if you get them from here: [url]http://www.dinanbmw.com[/url]

i'm thinking about the is3 complete conversion for my invisible z8.

In a nutshell, yes. But it depends. Different manufacturers provide different levels and/or types of customization.

Some things (if provided [Hypertech]) that provide clear benefits are higher tranny shift rpm(auto only), firmer tranny shifts(auto only), accounting for different tire diameters and different final gear ratios, etc.

When reprogramming the engine tuning (usually more and faster timing advances) keep in mind that this usually leads to detonation which engine management systems automatically counter by reducing timing. To prevent this, one or both of the following techniques help a lot...install a lower temperature cooling system thermostat and use a higher octane fuel (including the use of octane boosters). There is some debate that the engine computer eventually accounts for the changes and your left not much net gain. To counter that, get a complete custom programmed computer(SuperChips).

HTH

Thanks for the posts, I guess I'll save my money and just buy better Spark Plugs tomorrow.

Get the supercharger.......[:D]


[flag]

Get a turbocharger, much more efficient.

superchargers are somewhat better because there is no "turbo lag"

True however, performance decreases as they get warm. there's a reason all race cars are either turbocharged or naturally aspirated. Also since depending on the SC, it could be belt driven which causes more drain on the engine. A well developed engine with a turbo can be developed to the point where there is little or no lag.


[b]M4[/b]: Chips for turboed or supercharged cars tend to work with a huge effect as what it really does is bump up the PSI the charger puts out and advance fuel and timing to meet the new PSI level. Chips for naturally aspirated vehicles such as US domestic trucks are not nearly as effective and most if not all REQUIRE premium fuel to work. Hypertech is not a chip in the technical definition but a reprogrammer and some people notice an effect other don't.

I had a Superchip in an '87 firebird with the 2.8L V6.  While there's only so much you can do to a V6 before adding 2 more cylinders, the superchip did make a bit of a difference.  I noticed that it did pull a little harder in first gear, and got about 200 RPM closer to the redline before the 1-2 shift.  Not revolutionary, but definitely worth the $80 investment and 20 minutes of labor for installation.  It would stay neck and neck with a 305 Monte Carlo SS until just after second gear.

Bear in mind, though, that 93 octane will be a requirement after you go to that chip... although I never ventured lower to find out the consequences.

Chips now a days are in the several hundred dollar range. And if you go to lower octane you get engine knock.

Engine knock = BAD

Fellas....engine dynamics not withstanding...

I recommended the a supercharger because Nissan offers a model with an Eaton-type postive displacement blower as factory equipment.

[:D]

ThellUrider: Turbos are great but most people either dont have the money or dont have the patience to put one on...or two. Superchargers are cheaper and easier to maintain. My ATI procharger is intercooled just like a turbo. Its not as efficient as a turbo but it still kicks the ass! Someday I'll have two turbos on her!!

M4, unless you have some decnet mods a mail order chip is  a bad HP/dollor investment. Id recommend underdrive pullies or exhaust mods for the best bang per buck...the dyno tune is the best way for a chip.

Couldn't agree more. I was just saying that turbos ARE better than SCers but there are no turbo kits available for trucks. Superchargers are easier to install, and don't require ECU reprogramming. Superchargers are a great way to go. I never said they weren't. And if its intercooled all the better! [:D]

Editted to add: [b]M4[/b] Nismo, Nissan's performance division, may offer a supercharger for your application already. I don't know what year your Xterra is (can't remember from that last thread)  but the current ones are S/C already which may be wher the chip's hp claims are coming from in which case it should work. I just wouldn't buy it off of Ebay.

Thanks,

All I am wanting is a little extra "kick" Not a damn supercharger. [:D]


I mean a SC would be fun, but just a little more than I am looking for.

i bought a SuperChips MicroTuner for my 302 Ford PU about a year ago.
I got "a little extra kick" for sure.  Money well spent.
It lets me play with shift pressure, and shift points, for each shift of the auto.
It certainly gave me "a little extra kick".
I think all it really does is adjust the engine
parameters to make use of the higher octane fuel
that must be used with the SuperChip.  
I can revert to stock programming anytime, but
hell, I can't go back now - no matter what the
cost of premium fuel.  
Go for a tuner if one is available, then you can
have a smile on your face every time you fire it
up, like I do.
DanM

I was watching some car show and they put a chip & K&N filter on a C5 Corvette.  It did increase rear wheel HP & torque, but I don't remember how much.

You didn't really mean that.  Dragsters are supercharged, not turbo.  Road course cars don't have to worry about turbo-lag because once they get 'em going, they can keep the turbo spun up and avoid the lag. Ahhh, the sound of pop-off valves!

I'll not argue the super/turbo thing since I think you are right.  More HP/lb

I have read that the performance chips will mess up the vehicle one way or the other, the vehicle designers have it figured out for the best in the long run.

A modified ECU EPROM can make slight increases in power and still be street legal with little or no worry on grenading the engine on naturally aspirated engines.

As to the supercharging, there are things to consider.  First, you will definitely have to reprogram the EPROM to get any appreciable increase.  Why?  Injector sizing is fixed and at maximum power, the injectors are operating at their maximum duty cycle.  No more power without more fuel.  Upgrading injector sizes will require a reprogram to maintain driveability.

Superchragers are easier to install as the plumbing is cold.  Turbochargers require exhaust modifications with extreme precision.  If thermal expansion puts too great a load on the turbo, it will never last.  Also the EPROM needs a serious  reprogram.

I went from a sedate 90 Hp in my Jetta TDI to 115 with just a chip.  Diesels almost always operate with excess air so its a bit different...turbo boost builds immediately as its a variable nozzle turbo and is a bit on the small side for the power the engine produces.  I had to modify the boost control because it would exceed safe limits and saturate the boost pressure sensor at 29 PSI.  Oh yes, to deal with this increased air, I also installed larger injectors which brought me up to 153 WHEEL horsepower.  Now I need a new clutch and intercooler.  In cold weather, I get clutch slip in 4th and 5th.  Wheelspin in the others.

It still gets 48 MPG when I'm not zooming to 60 in uder 7 seconds :)

Upsolute with .205 Bosch remanufactured injectors.  This is dyno verified power.  The only other modification is the boost pressure control.  With all that fuel and boost, the stock control does not have the authority and overshot the requested boost with a huge undershoot as a result of the correction.

With the boost controller add-on, overshoot is a thing of the past and there is nil undershoot.  The response is classic critical damping.  With devices like Dawes etc, the overshoot is prevented at the expense of huge undershoot.  Getting consistent dyno numbers is then a real bear.

Before I bought the car, the prevoius owner had experienced a turbo failure...even in stock condition, this VNT 15 is right on the margin.  

Check out some of the performance auto sites. I can specifically recommend www.thirdgen.org  It is primarily a 3rd gen Camaro/Pontiac site, but it has LOTS of info on performance chips.

General concensus is there is not a lot to be gained on a STOCK motor with a chip. As several posters correctly pointed out, most aftermarket "performance" chips just bump timing slightly.

If you compare the actual programming of an aftermarket "performance" chip to a stock chip you will not see a huge difference.

Now if you are talking about a modified motor. i.e. freer flowing exhaust, bigger cam, ported heads, ported manifold, bigger injectors or some combo thereof an aftermarket chip can make a huge difference.

The catch is that not just any aftermarket chip will do. It has to be custom burned to your setup and tuned by reading O2 levels and measuring performance.

I have recently been learning how to program and burn chips for my TPI Chevy. There are big gains to be had, but they do not come easy, nor do they come with just slapping in an aftermarket chip.

If you are interested in burning chips, check out www.tunercat.com or www.moates.net

Sorry if this wasn't what you wanted to hear, but I hope the info/links are at least useful.

-Z

edit: spell