Will the fx 8350 bottleneck two gtx660 in sli?

No it won't bottle neck it but it is kind of pointless. The problem is that while SLI (and Crossfire) can help with rendering it does have it's problems especially if you are SLI'ing two lower end or mid end graphics card. Doing this can cause a bunch of problems like lag, micro stuttering and bad FPS. You are always better with one higher end video card than two lower end cards. In your case you would be better of with one GTX 660 TI, 670 or 680 rather than two GTX 660's.
 
if he already has a single 660, sure get another, but if ur buying both new then get a better single card, i heard sli 660s in certain games beat a 680, but not everything will utilize the sli configuration and avg 660 goes for $220, and sli will cost the same as a single 680