I had a fuel problem I couldn't seem to solve, see here:  http://amccars.net/cgi/yabb2/YaBB.pl?num=1323010482;start=all
Holley tech support tried helping over the phone, always hard to offer help that way. They answer the phone on saturdays, got to give them credit for that. It's actually harder to get them during the week.
 Once the problem was identified as defective machining, as in a hole was not drilled to the proper depth, they took my old carb back and sent me a new one right away. Turn around was fast and hassle free. Holley stands behind their product.
 
Dave Z

Since NASCAR went to fuel injection, Holley needs to take good care of their carb customers. I live in Bowling Green where Holley headquarters. There's a pretty big Holley clone manufacturer here as well and they also give great customer service.