mmosel wrote on 08/05/11 at 18:45:01:


The red sealant is only good for maybe 400 degrees F sustained.  I know the package probably says 500 with 600 intermittent, but this is pretty tough duty for the sealant,.... hi sustained temp, lots of vibration, pressure pulsing, etc.

The exhaust header near the head will be in the 800-900 degree range at full throttle.  I wonder what the temp will be at that joint on a hot day going up a slight hill at a steady 70mph.

drums1 wrote on 08/06/11 at 20:33:20:


Zackly

mmosel wrote on 08/07/11 at 01:01:38:



I still want to replace the one clamp   Good idea.  The skinny hose clamp doesn't have much clamping force, and it won't stay tight with the high heat, vibration, and repeated heating/cooling cycles.

If the sealant fails, then I'd have to take it off anyway.  I wish I could be more encouraging, but I fear you will get more practice at exhaust system disassembly.

I also wonder if wrapping the header pipe will make that joint hotter?  Yes, it will do that thing.  Wrapping the header does hold heat in,.. that is why header sweaters were invented!  Racers started doing it because the exhaust gas stays hotter, reducing its viscosity so it flows easier through the rest of the system.

Also, would wrapping the joint eliminate leakage if the seal failed? No.

mmosel wrote on 08/07/11 at 04:15:02:


Those clamps ARE a great deal.

As Drums1 offered, a proper joint needs no sealant.  

mmosel wrote on 08/07/11 at 04:50:55:



How much smaller?  Or,.. how much larger does the inner pipe have to be?

Muffler shops (and some racing shops) have equipment to expand or shrink tubing.  

Or you could try one of these: http://cgi.ebay.com/New-1-1-2-Tail-Pipe-Expander-Kit-Exhaust-/300585705304?pt...

One other thought would be to shim it with some thin sheet steel.

The overall effort should be to get the pieces to just barely fit.  If you have to literally force the pieces together to get them to fit over one another, you are on the right track.  (Almost an interference fit)  Then when you apply a heavy clamp, it becomes solid.

The muffler fit is spot on, super tight and the chrome clamp is great for that.

I was surprised by how much a simple hose clamp was able to tighten down the pipe where it connects to the header pipe. I think the new T-Bolt clamps will easily be able to tighten it down enough. They will provide more even pressure than the chrome clamp on the muffler itself. But if for some reason the T-Bolt clamp can't do it, then I'll replace it with something else.

I'll post some better pics of the clamps when they arrive, and report back on how well they actually 'clamp'.

Oh and I don't think I could expand the end of the header pipe, it's very thick, double walled hardened steel. If anything I'd get the transition pipe squeezed smaller, if they can even do that. Time will tell though if that is even needed.

I'm going to put the U-Clamp on for now, until the new clamps arrive.