4s lipo will be overvolting the fans by a little bit and may shorten their life. If they are typical 40mm fans, they only pull about 0.05A each. If so, you can read this to keep them at 12v.
BTW: You don't want to put the fans over the heatsink since the top is just plastic. For best results, the fans should be cooling the bottom.
any pic or link on quark heatsink?that's a helpful info Brian thanks a bunch one question what do you mean mounting the fan on the bottom and not on the heat sink?I thought that's why it has 2 places for the fans on the heatsink
Brushless Jammin Truggy on NEU 1515 2.5 D on Monster mamba max with maxamps 5000mah 6s Lipo
Gorillamaxx Revo CF version on Mamba maxx ESC with NEU 1515 1Y on Maxamps 4s 8000mah Lipo