Sounds like fun.😎

Try three wraps of Teflon tape on the threads And don’t over torque.  I’d suggest new bolts if It continues.

Bullet Bob wrote:

You might be over torquing the exhaust manifold bolts. Use the torque specs,  they matter.

Trivia Time:
 There has been a lot of study on hardware torque. It was done on the material of the hardware and the amount of stretch of the hardware and the clamping force of the pieces that they hold. It was discovered that there is a small area where the torque holding force is at its best. Too tight or too loose of a torque allows the hardware to loosen. Once hardware has been stretched beyond a certain limit, it's no good. The aircraft industry has OKed and demanded the use of proper torque instead of some kind of safteying device (saftey wire or pal nuts) in a lot of applications.

What gaskets are you using?

I used industrial grade  stainless socket head cap screws, straight up with no lock washers.
With SHCS’s you can use a Bondhaus ball end Allen wrench for easy on and off.
I have mentioned this many times in the past that I am using Prothane motor mounts. They seem to substantially limit the amount of engine movement which I am sure keeps my header bolts tight, I don’t even think about them anymore  other than one of the things on the check list at the start of each driving season.

Also, an exhaust crossover that stiffens up the entire exhaust system will make gaskets last longer and bolts will not back off.
I tend to tighten my header bolts really tight, but have never had any back off.

MS wrote:

What gaskets are you using?

Hedman Headers, Fel-Pro Gaskets.

I ordered Stage 8 hardware.  Will install this weekend and then check for exhaust leaks this weekend.  Next week car goes back to the exhaust shop to fix the crappy custom job and gets registered.  Can't totally rule out that exhaust isn't coming from collector.

After many years I've noticed intake bolts are always loose a year later and exhaust is some what. I tried to see if they are just backing out, but it seem they stretch (on the intake) and if you just keep retorqueing they will break . Headers, I never use a head side gasket, just red silicone ( hi temp), or a metal gasket if available.

Somebody gave me a set of those Stage 8 bolts once, many years ago.   About half of them could not even have the lock clips installed due to header tube clearance issues.  The ones that did get installed rattled so loud they could be heard in the driver seat.  Needless to say, they were quickly removed.   Those things are for Chevy engines. The solution is a very tightly torqued bolt and good gaskets and a crossover pipe to hold things rigid.  And THICK header flanges help, too.

TremendousWand wrote:

MS wrote:

Somebody gave me a set of those Stage 8 bolts once, many years ago. About half of them could not even have the lock clips installed due to header tube clearance issues. The ones that did get installed rattled so loud they could be heard in the driver seat. Needless to say, they were quickly removed. Those things are for Chevy engines. The solution is a very tightly torqued bolt and good gaskets and a crossover pipe to hold things rigid. And THICK header flanges help, too.

hmmm.  well I'll see how it goes.  If this is still a problem after a few months I may try another approach.

I have the Stage 8 bolts on my BBK headers and have no issues with them.  Yes, you need to file the clips to get a proper fit to the header tube, but mine have not failed me.  I previously had Hedman Headers and did not use "locking" style bolts and had to re-torque, or replace, header bolts, constantly.  The Hedmans had a 1/4' flange, while the BBKs has a 3/8" flange.  I believe that the thicker flange contributes to less issues with the bolts vibrating loose.