i think at first his carbs were so/so some bolted them on thinking it going to help alot or many may of tune them were just be way off on jet.metter plates .or CFM over the years after the holley deal he rework the carbs more not to use much of holleys parts . i re built some of them .never seen any thing that was that work much better then a good box stock holley would do . for most guys . i could say things about the holleys as they were pushing out junk . i have a holley HP 9377$$$ that some one beat the main body.. dents all over it called told them .they said thats was why they made gaskets.