On some engines they work, on some they dont. I had a JET Stage II one on my 2000 Dakota. I had the recomended 180 deg t-stat, new air intake, exhaust, etc. I could tell that it had a bit more low end torque to it. Not a lot, but a little. To tell any diff at all though, you will have to at least have the intake & exhaust done. Since you have that, it might work for you. Just remember, if you get one, after you put it in, undo the positive battery cable, and let it sit for about 10 minutes, then reconnect it, crank up, and let it idle for a minute or two. This gives the motor a chance to reset and adjust for the changes that the chip makes.
Personally, I like the Hypertech programmer better.

You're not looking at any serious gains.  Its just a recurve of the fuel map and depending on the transmission, new shift points.  You may get a little more than normal out of it but you have a cat back exhaust.  That is, if they have a map for your engine with that exhaust.  

Heck Wave..i thought you were talking jetskis...they do have upgrade chips for the 4 strokes now. Those skis are going 80 mph in a drop oof the hat.

I love speed on water.

[hijack mode] Do you still have your ski? Just curious...

Quoted: Yep still have the '99 Yamaha Waverunner GP1200, and I thought 63+ mph was pretty good on the water!

Yep..65u engine 135 hp...if you ever want to go faster..lemme know. I just sold my triple-piped '98 GP, it will GPS @ 72 mph all day. And very quick. I also have a single piped Super Stocked '98 GP. Great wave jumper and still the quickest dog in the water.

I also have the new Kawi STXR..great pwc. Best all-around personal watercraft since our GP's.

Quoted: Yep still have the '99 Yamaha Waverunner GP1200, and I thought 63+ mph was pretty good on the water!

And what is its on-board armament?

I ordered a Jim Wolf chip for my 300ZX Twin Turbo back in the 90's.  It worked well but it wasn't because of the chip. It was because of these .22 sized nozzles that they sent to install in the Turbo's plumbing. They helped "fool the system" to allow it to build 14lbs of boost instead of the stock 9lbs.  The chip only changed the fuel mapping etc. in order to keep the fuel/air mix right.  Listed HP increase with air intake and catback should have been about 90hp.

Quoted: Yep..65u engine 135 hp...if you ever want to go faster..lemme know. I just sold my triple-piped '98 GP, it will GPS @ 72 mph all day. And very quick.

THAT"S JUST NUTS!!  WOW!!! 72 mph on a Jet ski??  I don't know weather to be impressed or scared for your safety?!

When you go that fast do you wear any protection?

Sgtar15

Quoted: Quoted: Yep..65u engine 135 hp...if you ever want to go faster..lemme know. I just sold my triple-piped '98 GP, it will GPS @ 72 mph all day. And very quick. THAT"S JUST NUTS!!  WOW!!! 72 mph on a Jet ski??  I don't know weather to be impressed or scared for your safety?! When you go that fast do you wear any protection? Sgtar15

[continuanceof hijack]

Yes..we wear helmets, gloves and footwear. I wear gloves and jetski shoes everytime out. If I am at a race, it is recquired..if I go jump waves, helmet.

The new Yamaha triple-piped GPR's will run 80 mph all day everyday. The Yamaha GPR also holds the world record for pwc..87.5 mph in Guiness book, 90 mph spikes. Thats pretty fast without NOS. 250+ horsepower out of these water beast now days...

I do love them so. Lots of fun and east to care for..like a motorcycle.

Since the Xterra you have is supercharged, just about any chip that SUCCESSFULLY remaps the fuel will do very well....

Some don't do it very well.

What are their claims??

Has Steve Millen done anything with the Xterra?  I would put my money on him to get good results before anyone else.

He did wonders with the Maximas, 300TT's, and a Pathfinder as I recall.

I still think the pulley swap would be a good start......

HTH.....

They work well on some engines, but more often the not, you'll notice very small or if any hp gains and you'll get worse gas mileage and need to run premium gas now due to the advance in the timing.

If you have an auto alot of times they'll firm that shift up.

Quoted: Well the Supercharged Xterra's require 91 octane anyway.

Being supercharged you need to be really careful you don't go to lean with the fuel mixture,  you can get some nasty pinging and spark knock if the timing is too far advanced.

I'm sure when they reprogram your chip they will take that into account.

One of the other things to consider is what you want out of the truck.  If you are making a street drag type of truck, you need to let Jet know that.  If you want a powerful offroader,  let them know that too.

Also, have you though about a gear ratio change?  That will give you biggest bang for your buck out of any mod you can do to your car or truck.  If you more acceleration,  go with a lower ratio and vice versa if you ant more top end.  It sounds like you want more low end.  In that case,  lower the gear ratio and you will notice a HUGE difference,  way more that the chip can give you.

By the way,  I know a guy with a Duramax Diesel that did the chip and he can smoke his tires now.  That thing added some sick horsepower and torque.

All the reviews and tv shows that have put them in for tuning, doesn't seem to make sense to get one. For 300 bucks, there is definatly more bang for your buck out there.
The best I remember seeing is like 15-30 hp gains, and that is on the high side. They ran them on dyno's before and after. Now some of the curves were better, that is better pulling through the whole range,but I still could not see it being worth it.IMO

Well in your case, I may have take that back seeing again what you already have.
You are limited on cams since it is supercharged. But that would be my first under 300 dollar change.
Exhaust which I see you already did.
Though I wouldn't, there is always a fogger kit. You could add 50 percent to your numbers with that, way under 300.
Then I guess messing with the fuel injection is next, but I believe everyone of those changes requires a computer mod.
So I guess I only have 1 that would be more bang for the buck and that is the NOS system, but again I don't like them just because I would rather it be normally asperated.

Quoted: Quoted: For 300 bucks, there is definatly more bang for your buck out there. Such as?

Double that and like I said,  you get your gear ratio lowered, you will be amazed at the difference.

Gears is ALWAYS a safe bet and the more torque your engine puts out, the more you'll notice it.

Generally speaking, headers will net you the biggest gain if you going to add one thing.

Put some gears out back and headers and your engine will feel totally different.

Those were the best mods even when I wasn't born yet!