I'm not sure about the VIAR compressors but, I ran my ARB twin under my hood for awhile and it would always shut off because of getting too hot after about 3 tires (40"). Sometimes I would get all four, but then it would definitely shut off and I couldn't help my buddies air up. I moved it to the back of the Jeep (inside) and it does great now. Last time out we aired up 3 jeeps in a row with it. I made my own bracket and mounted it above the driver's side wheel well.
18 JKU Granite Crystal- 4"lift, 40s, UD60s
07 Red Rock Crystal JKU - Sold