Buying Holley Cores Look for broken base plates. Original bases are hard to come by. Aftermarket bases are not the same casting designs. They will work and are correct but have additional meat in the casting and you can see it. Look for stripped bowls, inlets and the needle and seat threads. Correct #'s on the metering blocks. That is very important. Some you can't get. The best thing you can do is take someone who knows, or at least another set of eyes to see if you missed something! Do your homework before you go so you don't buy something you don't want. And know your numbers!!!!

Buying Quadrajet Cores Check the long bolts that go all the way through the carb. Make sure it has not been overtightened. This can warp the carb beyond repair. Check the inlet threads and make sure they are not stripped, we can repair that but it costs more money. Check your I.D.# and the date!!. The date is the four digit # under the I.D.# and an example is:  3029- would be the 302nd day of 1969-1979 you have to figure out which decade.

The Biggest Problems..... People won't clean the tank out. They would rather try to drain the gas out instead of pulling the tank and having it boiled clean. Replace the fuel pump and purge the lines before you hook up the carb, it is the right thing to do!! Parts are becoming hard to find!!!!! Good AC Delco or Motorcraft is at the point of gone. Holley parts are not a problem, but factory parts are usually only avaliable at an obsolet part dealer and are not cheap!! The Holley formula for figuring carb c.f.m. is simple:  To figure the size of the carb you need for your application.  The formula is: cubic inch times highest rpm = then divide by 3456 ='s your c.f.m. rating.