Is there specific mods that must make tune or there are another mods don't need to do it? What are they?

 

If I understand the question, you're asking which mods REQUIRE a retuning after installation and which do not.

For simplicity, let's start a list of those that DO require retuning.

Most engine mods that produce additional horsepower (heads, cams, aggressive MAFs)
rear differential gear ratio changes
torque convertors (not all, but some)
tire diameter changes (may affect the speedo)
some intakes (air flow ratio changes)

I'm sure people can add others to this list.

In short, most things that change the drive train may require some degree of retuning.

Most other mods do NOT require retuning -- that being said, even a stock, unmodded car can gain hp/tq with a retuning. The stock tune is normally for EPA emissions compliance, not for performance.

Hope this helps.

 

He's right, every car benefits from tuning. I had mine dyno tuned last week and picked up 11rwhp and 11ft lbs, all across the power band too, not just at the peak. The car was set up slightly rich from the factory (12.6 to 1) and now is just right for good power (13 to 1) In my case I'm going to pick up even more performance at the track since we also raised my shift points by 3mph and deleted torque management. The trans now shifts into the next gear much quicker at WOT without any lag. I didn't baseline the car before the tuning, but I bet I picked up 3 tenths very easily.

 

is tuning safe and emission friendly?...will i have problems later on....this guy Brian i kno on the board has Kooks LT's installed on his GMMG and he had it installed at LS1speed if im not mistaking...and they did some tune if i remember him correctly?...is that a good thing to do...or is it some special type of tune?