use anti-seize on rocker stud-to-head threads?

Are you sure Trick Flow said no lubricant? I know you never want any thread locker in there. I use ARP assembly lubricant for everything that doesn't get a sealant or thread lock. (see page 3)
ARP lube at SummitRacing




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Rick - as long as loctite isn't used on a thread insert, I don't think it makes a huge difference either way. NeverSieze, AFR moly lube, oil - any of them should work fine. AFR also makes a thread sealer that is a moly lube also - I use the stuff on everything -- even works great to lube the back of disc brake pads.

why can't you put threadlocker on a rocker arm bolt?

I give up -- why can't you?

Rocker arm bolt is different than what he's dealing with which are stud mounted rockers. He has a stud that screws into the head, the rocker fits over the stud; a nut goes onto the stud to hold the rocker, and an allen head loc-screw screws inside the nut to lock it down against the top of the stud. Some manufacturers use helicoil inserts in their stud holes to help reinforce the threads (they're cut into the relatively soft aluminum head). If you put thread locker on a bolt/stud that's going into a helicoiled hole, there's no tellin' what's gonna happen if you try to remove the stud --you may pull the helicoil out too.

You didn't annoy me - was just havin' some fun.

Cast iron heads are actually in the very small minority when you look at cars and engines on a global basis. At 10-18 million new cars/light trucks a year for the last 30 years, there have probably been at least 200-250 million engines built with cast iron blocks and aluminum heads. It's been the standard in smaller engines for years. In fact, it's getting difficult to find cast iron blocks anymore - those are going to aluminum as well. Having driven mostly imported cars since the early 70's, I haven't owned a car with a cast iron head since the 55 Chevy I drove in high school. Nothing at all to fear there -- the oem manufacturers wouldn't use them if they weren't confident in their ability to perform. As for performance - well, unless it's prohibited by the rules (in some classes/sanctioning bodies it is) almost all performance engines ever built in the top echelons of any kind of racing you want to name - drag racing, NASCAR, F1, CART, World Rally, any motorcycle racing, etc. - are equipped with aluminum heads. They're lighter, they're easier to cast and machine and repair and they're reliable. You do have to be sure your cooling system is up to snuff - they don't tolerate an overheat as well as a cast iron head will. The cast iron head doesn't lose as much heat - so theoretically you could make more power with them, but this is offset by the ability of the aluminum head to allow more timing to be run and to resist detonation better than an iron head - so it's kind of a wash. Might as well come into the water - it's only a matter of time before all blocks/heads are aluminum. We get closer to it every year.