1) I looking for a 2x8 low drive
Do you plan to run this mobile or as a base. Mobile you're going to need a big alternator + extra batteries.
Open your wallet - new high output alternator, new batteries, new cables, probably new hardmount mobile antenna if you don't already have one.
Base - you'll need a big ass power supply, open your wallet again. You'll need a 5kw rated base tenna.
2) i already have rm italy but i need to put around 10 w am dead key to drive it
Your RM italy amp should not need 10 watts deadkey to drive it. What amp model do you have?
3) xforce amp is a other kind of amp....i hear i need to have max 2w input dead key and modulation do the rest.....is right??
Recommended deadkey output on the low drive 2 x 8 Xforce is 150w so you'll set your radio to achieve that number. It could be 2w it could be 4w, you set it by what the amp needs to achieve the recommended deadkey.
4) In the description we have this:
Typical Modulated Power Output (PEP) 1350-2550 Watts
Well.....how i can reach 2550w?? Voltage??
Answer: You won't achieve that wattage.
You'd be better off to explain your current setup first - vehicle, antenna, radio, amp, wiring, alternator, etc. Then people can explain to you what is involved with setting up a 2 x 8 amp.
90% of CBer's are not going to run larger than a 4 pill because either
a) they don't have the money to invest in a system to support a larger amp
b) they don't have the knowledge to properly install and setup a larger amp system
c) they don't need an amp that large as it's basically a waste of money for the average CBer.