I have had my 68 327/350 HT since it was new and over the years I wanted to buy a backup carburetor. I took the numbers off the one I had and went to a chevy dealer. They told me that the carburetor I had didn't exist. They checked it out with Rochester and verified that I had a different setup that they could not identify. NCRS say I should have a 7028219 but what was on my engine was a 7029224. I bought a 219 carburetor and it runs terrible. I rebult my original and it works fine.

Anyone hear of this difference??

I looked that number up in my black book. It does state that you should have 7028219. But what I do notice is that for 68 they all start with 7028. That was the first year for the Quadrajet so anythig is possible. For 69 the numbers all start with 7029. Maybe your car was a late 68 and they were playing with different carbs or they ran out of that carb and used a different design because of it being a 327.

I think you must be right. I have discussed with NCRS and that is what they suggest. They say that also the dealer may have replaced the Carb before delivery to fix a problem.