ProMaxx FOR85XN Replacement Cylinder Head

I've given them a four star rating only because I don't have an extended number of miles on them yet. However, I was able to order these in a time crunch and have them delivered in two days. That allowed me to stay on schedule. That was actually pretty amazing. Next, they were packaged well, and they installed perfectly with the new ARP studs. I had not one glitch with anything. Nothing I saw indicated anything less than a perfect replacement for a time sensitive engine repair where I could not afford to wait n having my originals checked out and remanufactured. Fast forward, two days after I buttoned the engine back up, I hooked up to a 10,000 lb trailer and towed 2500 miles. As of now, I'm probably 3500 miles past the installation and initial fire up on these heads, and they are performing exactly like the originals did. What more could I expect? I'll let you know in another 200,000 miles if they hold up as well as the originals did.

about 15k on them. No issues

Pro Max needs a guy in china over seeing production! My heads arrived and had all the valves at differant depths fron003 to 015 they spec @ .013 - .025 .020 IS PREFERED! not all over the place. these motors use valve depth to determine compression. So I spent 800 bucks on a vavle job and blue printed them myself. Not to mention they didn't have square dimensions but wedge instead of rectangle 1 of my exhaust manifold bolt holes needed to be tapped the correctly. They do have good valve seats though and are square where they need to be but having the whole job done in good old red china is what it is. They say 3-5 days but they have to order them from china so it will take 3 weeks. Thats what it takes for me to get my products made there if I wantedthem done there. XDPwas great in getting me the product but Pro Max has a quality issue I'd buy from another using the same supplier. If you meet the min you can have your name on them also from the same guy in china. And have them blueprinted.