[Troon2004]

I've read a number of posts regarding issues with header bolts coming loose/having to be re-tightened after new headers have been installed.

For those who aren't aware of it, Stage 8 makes a "locking" header bolt that they guarantee will NOT come loose under any conditions.

The bolt "kits" can be purchased from a number of sources and cost about $50.00 - cheap insurance and a laborer saver later:

Stage stage88906 Stage 8 Locking Header Bolts Ford 4.6L & 5.4L Modular - stage88906 Stage 8

[stlwagon]

Interesting Don. Was not aware of those.

[heavy metal]

I have used them,i try to sell them to all my customers who we install headers for,they are great.

[travelers]

They are a nice product but not necessary. I have the standard style header bolts and after cooling down re-checked and haven't loosened up. The regular ones are a lot cheeper. JMO

[Troon2004]

I only mention them for us "belt and suspenders" types.

[bigwilly43729]

Those stage 8's are nice, but a ROYAL PITA to get on. They are worse than the headers themselves. I have them and I couldn't even get the locking mechanism on the bolt itself.

That's probably why I had a leak...

[Troon2004]

Guys- I'm just the messenger.

[boss377]

The idea seems great at first, but unfortunately, it is almost impossible to install the locking C-clips with the engine in the vehicle! Secondly, the bolts don't actually unscrew themselves so much as the gasket "crush" shrinks after a few hundred heat/cool cycles. This decreases the gap between the header flange and the head mating surface, making it seem like the bolts loosened. Header gaskets materials have improved in the past couple of years, and mfgrs have designed them to have more memory than the old aluminum-fiber type. I just made that up.....
but seriously, a good set of stainless bolts from Totally Stainless tightened to specs along with the FRPP gasket should give you good service and stay gas-tight with only one 300-mile re-torque.

[Troon2004]

Speaking of gaskets, Fel-Pro makes several types that have similar properties of not (crushing/shrinking under extended useage.

BTW, I don't know if anyone has tried this with their header changes but you can get to the bolts much more easily by taking the wheel well liners out (which isn't all that difficult).