How can I make my MacBook Pro faster and virus free?

MacBook Pro "Core i7" 2.8 13" Late 2011 Specs (Late 2011 13", MD314LL/A, MacBookPro8,1, A1278, 2555*) @ EveryMac.com

The above link is the exact MacBook I have and I am running OS X Mountain Lion

I download things all the time (illegally) and I am nervous that I've picked up a few viruses. I mainly download torrents. I had Shopos AV but I removed it as it really slowed my MacBook down and I am nervous that it actually gave me viruses. So now I have ClamXAV and it does pick up an infected file every now and then. Is there anything better? Why did my MacBook slow down? What can I do to make it faster?

Also I want to add more RAM, but I am not sure which RAM to purchase and how much these can really handle. Can you provide links and details for everything you suggest?

Thank you for your time and concern.

FYI I am really a windows guy, computer science major, and I am just getting into Macs now.

Dont talk about what you dl as we done talked about illegal activity on these forums and dont condone it.

If your worried about viruses download (legally of course ;P) ClamXav

For RAM goto OWC Performance Upgrades; FireWire USB SATA Storage; Memory, more at OWC click on My OWC and follow the prompts to put in your machine specs and it wlll show ALL RAM for your machine. OWC are a great company as they test there stuff on Mac's and everything is made for Mac's.
HTH

Cheers

No discussion of Piracy allowed here.

What true virus's is ClamXAV finding? I would bet you $$$ they are all Windows virus's. Only Malware on OSX to date is a very few trojans. For detecting any threat that would affect OSX, ClamXav is fine.

VinnyMonty26 said:

I download things all the time (illegally) and I am nervous that I've picked up a few viruses. I mainly download torrents.

Click to expand...

We do not condone, discuss. or assist with this type of activity at Mac-Forums (against the Community Guidelines).

Regarding virus's. Without getting into the statistics of how many virus's/malware there are (or are not) out there for Mac's...what do you expect to happen if you download things illegally??? Stop downloading illegally obtained software...and you will have nothing to worry about.

- Nick

To add to what Nick said, 2 of those very few OSX trojans came with Pirated Apple Software. Just a word to the wise! It's really not worth the risk. Pay for the software. Most of Apples software is very reasonable in price.