I spoke with Holley today and had a pretty in-depth conversation with their tech guys. They told me that though the problems appear to be in carburetors manufactured durring the end of 2005 and beginning of 2006, they have found that some made durring that timeframe have not shown any corrosion at all and some have had more corrosion than the one I posted pictures of. They told me I should recommend too my customers that they look at their carb and inspect them at the first sign of a problem. If it is corroded, they will replace it for free. I also asked about possible fuel additives causing the problem since ethanol is in almost all fuels now. They stated that they investigated that possibility and found it was not a factor. Their testing concluded that there was a "casting problem" that has been corrected.
My guess is they changed their process, supplier, or both to cut costs and it backfired. It's just a thought
