Magnum heads

I bought my last set of EQ heads in 2016. was the 3rd set Ive had my hands on. the 1st (around 2008-ish) was the best. the 2016 set was the only set I bought "ready to run" and they clearly WEREN'T!!! went on a freshly rebuilt 360 Magnum in my Durango and I got 6 miles out of it.... 6 FREAKIN MILES!!! Guides were not finish reamed, and stuck #4 exhaust which kissed a brand new piston!! I might have had 3 hours on that engine with break in and all.... ONLY "ready to run right out of the box" set of heads I ever bought. Being as how I had to have them gone thru with such little run time I wont buy a set of heads "ready to run" again. I'll buy them like my 1st 2 sets were (bare) and build them up myself. I went to EQ's warehouse in Chicago and picked this set up myself. I remember I got the last head from one pallet and the 1st off the full pallet next to it. No way to tell which pallet the bad head came from. I wound up buying another 360 Mag from CL with (then) about 1/2 the miles of my original engine, and having the EQs redone and they're on there now. back then they cost me $700/pair. and then after I got tired of looking at that Durango as a garage ornament 3 years later I found that 2nd motor on CL and got it back running. in 2019 it cost me another $250 to have a valve job done on those low hour heads to make them usable. I was not happy. and these were supposedly NZ heads.