Purchased to restore a Holley 1850-5. First, it comes with a 4.5" power valve instead of the usual 6.5" valves found in almost every kit. Primary donor seals didn't fit me, luckily I had one from the remaining set that worked. There were also missing plugs for the air mixture idle screws. I found some o-rings that seem to work instead. I bought a quick fuel rebuild kit for the last one I did and it was way better. It comes with a stamped "330" vacuum secondary diaphragm, which is at leastβ¦