Quadzilla Stealth 2 Tuner #S2TUNER-S

01-05 GM 6.6L Duramax (LB7 & LLY)

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(19 Ratings, 9 Reviews) Average Rating:
Very pleased
Ian (Virginia Beach) 9/1/2012 7:43 PM
You can't beat this tuner for the price. I average a little over 20 mpg at 75 mph (you're not going to get 30 mpg at 75 so don't believe the review that says so). I run the 70hp tune and the power is very noticeable. The 135 tune doesn't seem any faster than the 70 hp tune, but I think I have a fuel delivery problem and I'm not getting enough fuel for the tune. I would highly recommend this tuner until you can save up enough money for efi live.
Very Satisfied
Ryan (Vancouver BC) 1/21/2012 11:45 AM
I recieved the chip, two minutes later I was out in the truck installing it. Ten minutes after that I was black smoking hybrids? Enough said, This chip put an instand smile on my face just pulling out of the drive way at 2000rpm. Im running it on 90hp tune as I still have stock trans. I would highly recomend this chip, it's great bang for your buck. This is the only mod on my truck this far and the difference was huge!!
lots of power little smoke
Steve (indiana) 9/7/2010 11:06 PM
tuner gives you alot of power great drivability and gives you fuel milage but i was disapointed in the smoke department. if anyone know's how to make an lb7 smoke using this programer the help would be highly appreciated
Quadzilla Stealth 2
Mark (Ohio) 4/15/2010 6:08 PM
Well, it does add power. No change in mpg over stock. Anyone reporting different needs to actually calculate the mpg, not read the DIC which becomes terribly inaccurate with any tuner. Now the bad news. Any setting but economy has poor drivability at low throttle positions, such as driving in city traffic, 35mph zones etc. The tunes seem to throw all the fuel and timing in at 1600ish rpm, then the motor jumps up to 2100rpm, then the trans shifts to the next gear, and the rpm drops to ~1400ish rpm. Next, the tach hits 1600 and off it goes again. Driving slow like this in town is a pain, constant jerking. Really crude. If all you do is drive on country roads or highways, it's fine. You'll get more power.
21 MPG AVG...33 at 80 MPH
Jeremy (Sacramento) 12/10/2009 10:19 PM
Nice tuner. With the 135hp tune, I get 30 MPG at 75 MPH & 33 at 80 MPH (Flat road). I went from an average of 14 MPG to 21 MPG. WELL WORTH THE MONEY!! Have had the tranny go into limp mode when flooring it doing 75. If I drive it like I would without the tuner, it gets excellent gas milage. I also have an after market air filter only and 4" Magna Flow turbo back exhaust, no cat.
Stealth 2
Jake Osburn (Arkansas) 11/27/2009 12:49 AM
This is a great start to makeing some good power, this programmer will be able to make 400HP with a intake, exhaust. Watch out on the stock trans it does make enough power to hurt it if you still have the stock one!
Lincoln (Bradenton florida) 5/19/2009 9:28 PM
I was debating on this or ppe and im happy I had went with The stealth 2. The free overnight shipping was great and the chip is even better. I love the Power it gives off and easy install.. I highly recommend this to any people who want power and something easy to use. its just great.
Jesse (Wyoming) 1/18/2009 3:00 PM
This programer is pretty darn good. My Duramax has 230,000 miles on it and haven't had any problems with the motor. You may not want to go over the 90 hp setting thought because I have had troubles with my tranny going into limp mode over 90 hp but this probly has something to do with the milage the truck has. I have also had a problem with the programmer freezing up but it usually comes back if you give it a minute. It gives you smoke and power and the egt's can get a little high you need guages.
Anonymous (Unknown) 2/18/2007 12:21 AM
man I must say this tuner is pretty darn good!! I uploaded the 135 horse tune right off the bat and reset my trans. and off I went the pedal response is awsome not overly sensitive just real smooth it's real easy to drive without baking the tires off the rims and man does it pull hard my buddy has the ppe hot accelerator et eliminator with his set to full power on his lly powered 3500 dually theres no comparison as far as bottom end power the stealth beats it hands down!! now mind you that 3500 is heavy and I have an lb7 but still 135 horse verses 300 the stealth gets my vote and it does upload much faster than the ppe not trying to down ppe but if I had not seen both in action I would not have believed it myself!! needless to say I'm glad I got the stealth I can't wait to get my tranny built so I can get the unlock code for the 215 race tune.. Joe Herbert