With the new SN197 with the 4.6 3 valve motor do you really have to retune the vehicle after every upgrade? Some company's claim you do and some say you don't. What's the deal?  

i've got a '05 and my understanding is, to get the most out of each upgrade, you should tune it.  

I have an 07 that I just bought some aftermarket stuff for and installed and was wondering about the tuners themselves. I'm willing to buy one, but do you guys have any recommendations as far as which is better? Or at least which one NOT to buy. They all seem to do the same things and are all priced relatively similar as well.  

I HAVE THE NEWEST DIABLO PREDATOR TUNER PAID 400.00  USED IT 1 TIME LOAD TUNE  MADE BIG DIFFERANCE THEN 1 WEEK LATER  REMOVED TUNE SO IT CLEAR AND READY TO USE. GOT SUPERCHARGER BY SALLEN AND THE TUNE IT ALREADY   WILL SELL FOR  250.00 PLUS SHIPPING   CALL SCOTT 623 533 0447  

I have the diablo sport for my 07 as well. I love the tuning ability it has, I changed gears,and added several bolt ons, and was able to do a no hassle driveway adjustment without ever turning a wrench or tool to increase power after the parts. Most tuners are a good thing, but I have heard that the sct or the diablo sport tuners are the way to go. I have also heard that the sct tuners are the better ones for SC or turbo tuning. I have had great gains and results, from My predator tuner.  

Hello

Both the SCT and Diablo tuners are very good. But if you are using the canned tunes that come with them you are only getting half the power available!

Here is why. If I'm selling a one size fits all tune, it has to work for a guy here in CA with 91 octane swill. A guy back east can get 93 octane. A guy in Denver is at 5000 feet, a guy in the south has high humidty etc etc. The point is that unless YOUR car is on a LOCAL dyno in LOCAL conditions the tune must be more conservative.

Don't get me wrong the tunes from these companies, in fact you can add Superchips Inc to the list, are pretty good. They cost less too. I'm just saying that a good local tuner can do better.

You don't need a new tune for every mod but do for some. Any cold air kit that REALLY makes power needs a tune. A cat back will not. If you significantly change the way air flows in or out of the engine, change injectors or increase cylinder pressure, you need a tune.

Hope this helps answer a few questions.

Chris